Abstracts from:The 1st International Congress on Early Onset Scoliosis and Growing SpineNovember 2-3, 2007Madrid, SpainChairman: Behrooz A. Akbarnia, M.D.

Free Papers

Paper #1

The Effect of Early Anterior Fusion on Spinal Canal Size: An Immature Porcine Model

Muharrem Yazici, M.D., Guney Yilmaz, M.D., Murat Pekmezci, M.D., Kenan Daglioglu, M.D., FC Oner, M.D.

IntroductionNeurocentral cartilage (NCC) is located at the posterior 2/3 of vertebrae and responsible for the growth of the pedicles and posterior vertebral body. The aim of this study is to evaluate the effect of anterior spinal instrumentation and fusion on the development of vertebral body in porcine model.Materials & MethodsTwelve 8 week-old domestic pigs had CT scans preoperatively and underwent anterior circumferential discectomy of the L3-L4 and L4-L5 discs. Anterior spinal instrumenta-tion was performed between L3 and L5 (L4 skipped). After 6 months their vertebrae were evaluated with CT scan for the presence of anterior fusion and vertebral canal size. The area of vertebral segments adjacent to proximal and distal instrumented segments was used as control level area (AC), average area of L3 and L5 was used as area change in instrumented levels (AI), and area of L4 was used as area change at arthrodesis level (AA). The percent increases in the canal area and total canal area were compared.ResultsAll subjects had documented anterior fusion. There was no difference in the canal diame-ters of three groups preoperatively(AA: 0.70cm2, AI: 0.70cm2, AC: 0.68cm2; p≥0.05). At the end of 6 months average canal diameter was significantly lower than control group in the arthrodesis and instrumentation groups (AA: 1.20cm2, AI:1.24cm2 , AC:1.41cm2; p≤0.001). The average canal diameters of the arthrodesis and instrumentation groups were similar (AA: 1.20 cm2, AI: 1.24 cm2; p≥0.05). The average percent increase in the canal area was significantly lower than the control levels in the arthrodesis and the instru-mented segments (AA: 72.6%, AI: 77.1%, AC: 110.1%; p≤0.001). The percent increase in the canal area between the arthodesis and instrumented segment was similar (AA: 72.6%, AI: 77.1%; p≥0.05). ConclusionThis study demonstrated that anterior spinal arthrodesis or instrumentation in the imma-ture spine may result in iatrogenic spinal stenosis.

Paper #2

Growing Rod Instrumentation and Vertebral Body Growth: A Radiological Investigation in Immature Pigs

Guney Yilmaz, M.D., Muharrem Yazici, M.D., Gokhan Demirkiran, M.D., Kenan Dagli-oglu, M.D., Cenk Ozkan, M.D.

IntroductionDistraction forces applied on growth plate of appendicular skeleton stimulate longitudinal growth. However the effect of distraction forces on axial skeletal growth has not been fully investigated yet. The aim of this study is to evaluate the vertebral body growth un-der distraction forces in immature pigs treated with growing rod technique. Materials & MethodsEight 8-week-old domestic pigs were used in this experimental model to simulate grow-ing rod instrumentation technique. Cranially T12-L1 and caudally L4-L5 vertebrae were instrumented by pedicle screws bilaterally, while L2 and L3 were skipped. Distraction between pedicle screws was applied at index surgery. The rods were then lengthened twice in a month interval. All subjects were evaluated with lateral spinal X-ray preopera-tively, postoperatively and at the final follow-up. The vertebral body heights of distracted segments (HD= L2 and L3) and control segments (HC= T9, T10 and T11) were mea-sured. Average vertebral body heights and the percent increase in the vertebral body heights were compared among control segments (n=11) and distracted segments (n=8).ResultsFour subjects were lost during the immediate postoperative period. The preoperative ver-tebral body height was similar in two groups (HC:10.97mm, HD:11.27mm, p≥0.05). At the final follow-up, the average vertebral body height in distraction group was signifi-cantly higher than the control group (HC:16.92mm HD:18.56mm, p≤0.05). The percent increase in vertebral body height was higher in distracted segments but there was no sta-tistically significant difference between the two groups (HC:54.1%, HD:64.4%, p≥0.05). Postoperative average vertebral body height in distraction group was significantly longer than preoperative measurements (HDpreop: 10.55mm, HDpostop: 17.49mm, p≤0.05). ConclusionThe vertebral growth continues during growing rod instrumentation. Distraction forces might stimulate also apophyseal growth of axial skeleton.

Paper #3

Results of Three Classes of Surgical Treatment for Congenital Scoliosis due to Hemiver-tebrae: A Multicenter Retrospective Review

Michael O'Brien, M.D., Peter Newton, M.D., Randy Betz, M.D., Harry Shufflebarger, M.D., Angel Macagno, M.D., Baron Lonner, M.D., Lynn Letko, M.D., Jurgen Harms, M.D., Alvin Crawford, M.D., Suken Shah, M.D., Paul Sponseller, M.D., Michelle Marks, PT MA

Summary42 patients with hemivertebrae (HV) and congenital scoliosis were compared based on one of three surgical treatments. HV resections with posterior instrumentation results in reduced surgical time, shorter fusions, less blood loss, and improved % correction but slightly higher rates of instrumentation and neurologic complications.IntroductionWe compare the outcomes of 3 surgical treatments for congenital deformities due to a fo-cal hemivertbra (HV). MethodsA retrospective multi-center database was compiled from 8 centers to evaluate patients treated surgically for congenital spinal deformity due to 1 or 2 level HV. The surgical treatment were: Group 1, fusion without correction (hemi-epiphysiodesis or in-situ fu-sion), Group 2, correction without HV resection (with or without anterior or posterior re-lease) and posterior instrumentation, and Group 3, correction with HV resection (anterior and/or posterior) and posterior instrumentation. ResultsForty-two patients, with two-year follow-up, were treated between 1991 and 2004. The congenital anomalies were: fully segmented, non incarcerated HV (n=32, 76.2%), incar-cerated HV (n=1, 2.4%), and semi-segmented HV (n=9, 21.4%). The distribution of sur-gical treatments were: Group 1: n=10(24%), Group 2: n=9 (21%), Group 3: n=23 (55%). Pre-operative curve sizes were statistically different: Group 1, 37° and Group 3, 34° were significantly smaller than Group 2, 55° (p=0.04 and p<0.01, respectively). The mean age of the patients was 8 years (range 1-18). The complication rate was 25%: Group 1, 20%, Group 2, 11%, Group 3, 35%. The % coronal correction at 2 years post-op was better for Group 3 (74%) compared to Group 1 (30%) and Group 2 (45%) (both p<0.01). A sub-analysis of Group 3 revealed shorter fusions in those treated with posterior only resection compared to the anterior/posterior techniques (p=0.05). ConclusionHV resection gave the best % correction 2 years post-op. It had a slightly higher compli-cation rate than the other two techniques. HV resection in younger patients results in bet-ter correction with fewer levels fused than either of the other two techniques.

Paper #4

A Retrospective Cohort Study of Pulmonary Function, Radiographic Measures and Qual-ity of Life in Children with Congenital Scoliosis: An Evaluation of Patient Outcomes af-ter Early Spinal Fusion.

Michael Vitale, M.D., MPH, Hiroko Matsumoto, M.A., Jaime A. Gomez, M.D., Michael R. Bye, M.D., Joshua E. Hyman, M.D., Whitney A. Booker, B.S., David P. Roye, Jr., M.D.

IntroductionThis study evaluates the pulmonary function and quality of life (QOL) of children after a posterior spinal fusion for progressive congenital scoliosis and compares them to those of healthy children. The relationships between radiographic measures, pulmonary function, and QOL will also be examined. MethodsTwenty-one patients 12.6 +/- 3.4 years old with diagnosis of congenital scoliosis who were treated with posterior spinal fusion were evaluated using radiographs, pulmonary function testing (PFT) and QOL surveys using Child Health Questionnaire Parent Form (CHQ). Some of the patients were treated with growing rods before the fusion and they were, on average, 6.9 years post definitive spinal fusion. Average age at initial surgery was 4.9 (1-10) years.ResultsForced vital capacity (FVC) (p<0.001), forced expiratory volume in one second (FEV1) (p<0.0001), total lung capacity (p=0.001), and vital capacity (p<0.001) were significantly lower than those in healthy children. The CHQ scores in our study patients were signifi-cantly lower than healthy children in physical function (p=0.001), general health (p=0.001), and physical summary (p<0.001) and significantly higher in emotional impact on parental time (p=0.036). Patients with larger thoracic curves had lower FVC (r = -.532, p= 0.075) and FEV1 (r = -.590, p=0.04). Patients with larger kyphotic angles had lower self esteem (r = -.560, p=0.008). Patients with larger thoracic curves have lower scores on family activities (r = -679, p = .011) and those with larger thoracolumbar curves have lower scores on physical domains (r = -.701, p = .008). Patients who had lower FEV1 (r = .526. p=.021) and FVC (r = .545, p=.016) had lower global behavior and family activities scores.ConclusionCompared with healthy children, patients with congenital scoliosis, treated with posterior spinal fusion at an early age, have significantly worse pulmonary function and quality of life scores when assessed at average 7 years following initial surgery. These data will add to growing literature which supports alternatives to early spinal fusion, such as fusion-less surgery, growing rods and the Vertical Expandable Prosthetic Titanium Rib (VEPTR) device.

Paper #5

How Does VEPTR Affect Pulmonary Function?

Hemal Mehta, M.S., Brian D. Snyder, M.D., Ph.D, Andrew C. Jackson, Ph.D, Stephen R. Baldassarri, B.S., Melissa J. Hayward, M.D., Michael J. Giuffrida, M.D., Vahid Entezari, M.D., Jay M. Wilson, M.D.

SummaryThoracostomy in conjunction with VEPTR implantation partly reversed the constricted hemithorax created in young rabbits thereby partially improving lung growth and alveolar IntroductionCampbell demonstrated that thoracostomy in conjunction with VEPTR implantation to expand the constricted hemithorax of children with acquired or congenital anomalies of the thorax and spine improves respiratory function and controls spine deformity. The mechanisms for the success of this treatment are unknown.HypothesisThoracostomy in conjunction with VEPTR implantation reverses impaired respiration by increasing the volume of the constricted hemithorax to allow partial resumption of lung growth.MethodsA constricted left hemithorax was induced in seven 5-week old New Zealand rabbits by asymmetrically tethering ribs 4-8. Thoracic and spinal deformities developed in the Dis-ease group (n=3). Thoracostomy and VEPTR implantation were performed at 10-weeks in the VEPTR group (n=4). Two rabbits served as Normal Control. At serial time points during growth, FRC and respiratory compliance were measured using whole body plethysmography. Lung volume, spine and chest wall deformity were measured using CT. Right, left and total lung volumes were calculated from sequential transaxial CT im-ages of the thorax. Histological analysis was performed on the dissected lungs. Measures of respiratory function, spine and thoracic deformity were compared using ANOVA and Fisher’s least significant difference.ResultsThe constricted hemithorax created in the Disease group was partly reversed in the VEPTR group. This allowed slight improvement in left lung volumes. However, due to the small number of rabbits, this result was not significant. A compensatory increase in right lung volumes resulted in normalization of total lung volume among the Disease and VEPTR groups. Alveolar morphology was significantly improved in the VEPTR group.ConclusionsPreliminary results indicate that VEPTR implantation partly reversed the constricted hemithorax created by tethering ribs in a growing rabbit model. There was slight im-provement in the growth of the affected lung and partial normalization of alveolar mor-phology histologically.

Paper #6

The Treatment of Secondary Thoracic Insufficiency Syndrome of Myelominingocele by a Hybrid VEPTR "Eiffel Tower" Construct with S-Hook Iliac Crest Pedestal Fixation

Robert M. Campbell, M.D., M. Smith, M.D., W. Allen, M.D., JW Simmons, M.D., S. In-score, M.D., B. Cofer, M.D., J. Doski, M.D., C. Grohman, M.D.

Secondary thoracic insufficiency syndrome in myelomeningocele is associated with lum-bar kyphosis, lordosis, or pelvic obliquity. Fusion or kyphectomy may correct angular deformity, but at the cost of growth of the spine with a high rate of complications. A modification of the VEPTR construct for congenital scoliosis has promise for treatment of this disorder.Methods0 pts. Avg f/u 5.75 yrs ( 2-11.5 yrs ) Unilat hybrids 8 pts., bilat 2 pts.ResultsSix had a marionette sign preop, none at follow-up. Ratio of diaphragm depth/abdominal height (nl <1) improved from 2.17 preop to 1.56 at f/u. Lumbar kyphosis improved from 43˚ to 26˚. T/L spine ht increased 5.8mm/yr. Pelvic obliquity improved from 34˚ to 11˚. Coronal moment arm of iliac crest s-hook fixation was 2.4 times longer than a theoretical pedicle screw at the same level. Asymptomatic hook migration through avg 39 mm “safe zone” of iliac crest was 24 mm (6.3 mm/yr, or 16% “safe zone”/yr ) Unilateral hooks mi-grated at 8.4mm/yr , bilateral at 7.4 mm/yr . No slow migrations required reseating. One s-hook incorrectly placed in the SI joint did require acute reseating.. Scoliosis improved from 73˚ to 46˚ . Average f/u VC (n = 7) was 39% normal. Average implant EBL 84 cc. Complications: 3 s-hook fractures, 2 rib cradle migrations, 1 skin slough, 4 wound infec-tions. There were no spinal infections. One patient died of respiratory failure unrelated to surgery.ConclusionsVEPTR expansion thoracoplasty with a hybrid VEPTR “Eiffel Tower” construct with s-hook iliac crest pedestal fixation can span the lumbar spine laterally with effective lateral torso/pelvis distraction elevating the diaphragm away from the pelvis with correct of spine deformity and pelvic obliquity without affecting growth potential of the spine.SignificanceS-Hook iliac crest pedestal fixation VEPTR modification is a powerful means to correct pelvic obliquity because of inherent biomechanical advantage of an extended lateral mo-ment arm compared to central spinal fixation, and spine infection appears be avoided be-cause the central skin scarring in myelomeningocele is not violated.

Paper #7

VEPTR in Non - Ambulatory Myelodysplasia Patients

John M. Flynn, M.D ., Norman Ramirez, M.D., Randal Betz, M.D., John Smith, M.D., Robert Campbell, M.D.

Non-ambulatory children with spina bifida are most likely to develop scoliosis. The dys-plastic anatomy of the chest wall in a paralytic child secondarily affects other organ sys-tems. Thoracic insufficiency may go unnoticed due to the child's limited physical activi-ties is and is due to increased sagittal plane deformity as the diaphragm invades the pul-monary cavity.The purpose of this report is to evaluate the patients with spina bifida and spinal defor-mity treated with the Vertical Expandable Prosthetic Titanium Rib (VEPTR) and in-cluded in the FDA Request for Approval of Humanitarian Device Exemption for the Ver-tical Expandable Prosthetic Titanium Rib.The FDA report includes 247 patients with surgeries performed by members of the Chest Wall Deformity Study Group. Twenty patients were myelodysplastic none ambulatory. Data from remaining 16 patients with adequate follow up was extracted from the FDA re-port and analyzed.The average age at the first surgery was 5 years; average follow up was 47.3 months. In nine patients the Cobb angle was decreased an average of 14.4°; in five patients increased 12.6°. Thoracic spinal height was increased in twelve patients an average of 3.2 cm. and lost in two patients 0.8 cm. Twelve patients improved and two patients deteriorated venti-latory function. Implant lengthening was done on the average of every sixth months and device exchange every 30 months. Complications in five patients were due to the severity of the decreased pulmonary capacity. Implant failure and skin breakdown occurred in six patients.The rate of complications reported in this group of patients lies within the range reported for spinal fusion using standard approaches. The number of surgical procedures increases due to the need for expanding the implants as the child grows. The advantages of the VEPTR are: surgical incisions are away from the midline avoiding the midline scarred tissue and allowing growth of the spinal column with improved space available for the lung.

Paper #8

Measurement of Forces Generated During Distraction of Growing Rods

Marco Teli, M.D., Giuseppe Grava, M.D., Alessio Lovi, M.D., Marco Brayda-Bruno, M.D.

Study designConsecutive series of measurements.ObjectiveTo measure the forces applied during distraction of growing-rods.Summary of Background DataGrowing-rods have been used for decades to treat deformities of the immature spine, with variable success. These rods are periodically lengthened by repeated surgeries, and fail-ure of growing instrumentation is often reported.MethodsDistraction forces were measured in 10 pre-puberty patients (mean age, 8 years; range, 6 to 11) undergoing the first distraction of growing-rods, 6 months after implantation for idiopathic scoliosis treatment. For each measurement, output from the transducer of a dedicated pair of distraction calipers was recorded at zero load status and at every 1 mm distraction, up to a maximum of 12 mm.Results10 measurements were obtained showing a mean peak force of 485N at 12 mm distrac-tion. In one case a single peak force reached 552N at 6 mm distraction.ConclusionsAt 500N no failure of instrumentation was recorded. This led to satisfactory elongation of the rods. The above limit is therefore to be regarded as the uppermost level of force to be applied during surgical distraction of growing rods.

Paper #9

Single Growing Rods (Review of 21 cases). Changing the Foundations: Does it Affect the Results?

Hazem Elsebaie, FRCS, M.D.

Study DesignA retrospective case review of children treated with submuscular single growing rod technique with proximal double claw and distal double level pedicle screws construct done by the author. ObjectivesEvaluation of a newer version of single growing rod technique inserted sub muscularly. Changing the foundations in the single rod may change the results. Background DataSingle growing rod techniques used to include proximally a single claw and many other constructs that have evolved over years, these reports were used commonly to be com-pared with the double rods. To the authors’ knowledge there were no reports on sub mus-cular single rod using consistently these foundations which are assumed to be and more powerful in correction. MethodsFrom 2002 to 2007, 21 patients average age 6 years ( 4 -9) underwent single growing rod procedures using pediatric Isola instrumentation and tandem connectors, 8 had annulo-tomy. They underwent an average of 4 lengthening ( 1- 9). Diagnoses included infantile and juvenile idiopathic scoliosis (13), congenital (3), neurofibromatosis (3), syndromic (1) and post hydrocephalus (1). Analysis included age at initial surgery, number and fre-quency of lengthening, changes in scoliosis Cobb angle, length of T1-S1 and complica-tions. ResultsThe mean scoliosis improved from 85° (range, 45° -123°) to 31° (range, 11°-61°) after initial surgery and was 36° (range, 13°-75°) at the last follow-up. T1-S1 length increased on average of 1.32 cm per year. During the treatment period, complications occurred in 7 of the 21 patients, and they had a total of 11 complications all were implant related in-cluding 4 proximal claw pull out, 5 rod breakage, one loose set screw of the tandem and one pedicle screw distal migration, there were no infections, skin complications nor neu-rological complications. ConclusionThe sub muscular single growing rod technique with proximal double claw and distal double pedicle screws seems to offer a valid alternative to the double rod techniques with comparable degrees of correction and less incidence of skin complications and infections especially in thin children with minimal subcutaneous fat.

Paper #10

Safety and Efficacy of Growing Rod Technique for Pediatric Congenital Spinal Deformi-ties

Hazem E lsebaie, FRCS, M.D ., Muharrem Yazici, M.D., George H. Thompson, M.D., John B. Emans, M.D., David S. Marks, FRCS, David L. Skaggs, M.D., Alvin H. Craw-ford, M.D., Lawrence I. Karlin, M.D., Richard E. McCarthy, M.D., Connie Poe-Kochert, NP, Patricia Kostial, RN, BSN, Tina Chen, BS, Behrooz A. Akbarnia, M.D.

Study DesignA retrospective analysis of patients with congenital spinal deformities treated with single or dual growing rods that had a minimum of 2 years follow-up. ObjectivesTo determine the safety and efficacy of this technique.Summary of Background DataGrowing rod technique has been used as a modern alternative treatment for young chil-dren with spinal deformities. There is no comprehensive study focused mainly on the use of growing rod technique in congenital spine deformities. MethodsA total of 19 patients with the average age of 6 years and 10 months (3 to 10) with pro-gressive congenital spinal deformities that underwent growing rod procedures with a minimum of 2 years follow up. The congenital anomalies included failure of segmenta-tion in 5, failure of formation in 4, mixed 5 and unclassified or not recorded in 5. The av-erage of affected vertebrae per patient was 5.2 (2-9). The average follow up period was 3 years 9 months (2 to 6).ResultsThe mean scoliosis cobb angle improved from 65.3 (40-90) pre-initial to 44.9 (13-79) post initial (31.2% correction) and 47.2 (18-78) at the last follow-up or post-final fusion. T1-S1 length increased from 263.8mm (192-322) after initial surgery and to 310.5mm (261-352) at last follow-up or post-final fusion with an average T1-S1 length increase 12mm per year. The space available for lungs (SAL) ratio increased from 0.81 preopera-tively to 0.94 post latest follow up. Five patients reached final fusion. During the treat-ment period, complications occurred in 8 of the 19 patients (42%), and there were a total of 15 complications out of 100 procedures (15%): 2 pulmonary, 2 infections and 11 im-plant-related. There were no neurological complications in any of the patients during the treatment period. ConclusionThe growing rod technique is a safe and effective treatment for congenital spinal defor-mities. There is less correction obtained at initial surgery compared with previous reports for the same technique in other etiologies. However, there was minimal loss of correction over the treatment period. The spinal growth and the SAL improved. The rate of compli-cation is acceptable. Paper #11

Pelvic Fixation of Growing Rods

Paul D. Sponseller, M.D ., Behrooz A. Akbarnia, M.D., George H. Thompson, M.D., Richard E. McCarthy, M.D., John B. Emans, M.D., Marc A. Asher, M.D., Muharrem Yazici, M.D., David L. Skaggs, M.D., Connie Poe-Kochert, RN, CNP, Pat Kostial, RN, BSN, Tina Chen, BS

Previous studies have not evaluated growing systems in which the distal anchor is the pelvis. This project analyzed the outcomes and complications of this population. 22 pa-tients were studied from 6 centers. Indications included severe pelvic obliquity, distal de-formity, or lack of satisfactory alternative anchor sites. All had a minimum of two years treatment with growing rods fixed to the pelvis. Diagnoses included myelomeningocele (4), cerebral palsy (3), congenital (2), arthrogryposis (1) SMA (1), miscellaneous/syn-dromic (11). Mean age at surgery was 6.1 ± 3.1 years. Mean preoperative curve was 86 ± 22°. Mean coronal imbalance was 9.7 ± 8.2 cm. Mean follow-up was 50 months. Iliac screws or rods were used in 17, sacral hooks used in five. Proximal fixation was with hooks in 12 patients and screws in 10. Dual rods were used in 18 patients; single rod in 4. Use of a distal crosslink improved construct stability. Patients underwent a mean of 2.9 ± 1.8 lengthenings. Mean curve improved to 47± 19° at final follow-up. Coronal imbalance improved to 4.4 cm postoperatively. Mean increase in T1-S1 length was 7.3 ± 2.9 cm during distraction. Seven patients have undergone final fusion at a mean of 10.8 ± 1.4 years. Complications: 6 patients developed deep wound infections; 5 patients had distal fixation complications, but all were salvaged. There were 3 rod breakages; this rate did not differ statistically from the rate for dual growing rods as a whole. Pelvic fixation may be used successfully as a distal foundation for growing rods. Both screws and hooks pro-vide satisfactory distal fixation. Pelvic fixation is a useful adjunct to growing rods for many children who develop severe syndromic or neuromuscular spinal deformity at an early age.

Paper #12

Iatrogenic Thoracic Outlet Syndrome as a Complication of VEPTR

Steven Mardjetko, M.D., Ahmad Nassr, M.D., Benjamin Crane, M.D., Kim Hammer-berg, M.D.

IntroductionAn innovative treatment for Thoracic Insufficiency Syndrome (TIS) involves a vertical expansion of the chest wall through a horizontal chest wall osteotomy and a distraction device (VEPTR). However, 10% of these patients demonstrate upper extremity neurovas-cualr dysfunstion following expansion. This study identifies potential etiologies for com-pression of the brahial plexus following the VEPTR procedure, and suggests strategies to reduce the incidence of this complication.Materials and MethodsA cadaveric study with a simulated VEPTR procedure was performed. A thoracotomy and sequential rib distraction was performed while manometric measurements were taken in three anatomic regions of the thoracic outlet. Also, a barium-impregnated putty was placd along the brachial plexus, and evaluated after expansion using fluoroscopy. A mid-clavicular osteotomy was then performed and this process was repeated.ResultsUsing the manometric technique described, a 20% increase in pressure was seen in the mid-clavicular region of the thoracic outlet after thoracic expansion. Reapproximation of the scapula on the chest wasll further increased the pressure within the thoracic outlet. constriction of the mid-clavicular region of the thoracic outlet between the first rib and clavicle was appatent using the putty technique. Mid-clavicular osteotomy alleviated this region of compression. A second region of compression was noted in the infraclavicular region of the thoracic outlet. This was secondary to a lateral displacement of the second and third ribs during the expansion thoracoplasty. This constriction was worsened by anatomic reapproximation of the scapula to the chest wall.DiscussionSurgeons should avoid any attempt to pull the scapula distal or medial to its anatomic po-sition. The utilization of mid-clavicular osteotomy to alleviate thoracic outlet narrowing after VEPTR procedure may be considered if compression is thought to be in the mid-cavicular zone. For compression in the infra-clavicular region, lateral second/third rib os-teotomy or resection may be another strategy.

Paper #13

The Development of Spinal Deformities Following Open Heart Surgery

Jose Herrera-Soto, M.D. , Kelly L. Vander Have, M.D.

Patients with congenital heart disease (CHD) are at an increased risk of developing scol-iosis. The purpose was to determine the prevalence of spinal anomalies in patients with CHD post open heart surgery.Methods221 patients post open heart surgery for CHD without congenital anomalies were evalu-ated. There were 132 males and 89 females with a mean follow-up of 13 years. Results59 patients presented scoliosis (27%), with similar incidence of scoliosis between groups. 18 presented moderate to severe scoliosis. 39% with moderate to severe scoliosis pre-sented with hyperkyphosis (>40 deg). All patients with severe scoliosis underwent spinal fusion, 9 female and 4 male. Forty patients (18%) presented with hyperkyphosis. Only 1/40 with hyperkyphosis had a thoracotomy (2.6% of thoracotomy patients). The remain-ing 39 patients underwent a sternotomy or combined procedure. There was no difference in those with cyanosis or not and the development of scoliosis or kyphosis. No difference between those with and without scoliosis and the age at the first procedure was found. Patients with multiple procedures were not at increased risk of deformity.There is an increased incidence of scoliosis in CHD patients. Sternotomy may affect coronal alignment as thoracotomies. But, it was shown to affect sagittal alignment. It is important for continued monitoring of spinal deformities as 80% of our severe curves de-veloped before the age of 9.

Paper #14

Health Related Quality of Life in Children with Thoracic Insufficiency Syndrome

Michael Vitale, M.D., David P. Roye, Jr., M.D., Hiroko Matsumoto, MA, Jaime A. Gomez, M.D., Randal R. Betz, M.D., John B Emans, M.D., David L. Skaggs, M.D.,John T. Smith, M.D., Kit Song, M.D., Robert M Campbell, Jr., M.D.

PurposeThe purpose of this study was to compare quality of life (QOL) of children with TIS and impact on their parents prior to and after the implantation of the VEPTR. We also com-pared the QOL of children with TIS and the parental impact prior to implantation of the VEPTR with previously published QOL of healthy children. MethodsAs part of the original multi-center evaluation of the VEPTR, Child Health Questionnaire CHQ was collected preoperatively on 45 patients who were subsequently treated with ex-pansion thoracoplasty using the VEPTR. The average age was 8.2 +/-2.6 and parent form of the CHQ was filled by the primary caretaker. Patients were divided into three diagnos-tic categories: Rib Fusion (RF) N=15, Hypoplastic Thorax Syndromes (HT) N=17 and Progressive Spinal Deformity (PS) N=13. ResultsThere were significant differences between the study patients and healthy children in physical domains. Compared with parents of healthy children, parents of children with TIS experienced more limitations on their time and emotional lives due to their children's health problems. In addition they had poor expectations for their children's health. There were no significant differences in CHQ scores in these children before and after the surgery except for a significant decrease in Self Esteem score among patients with HT. None of the domains in the CHQ had moderate or large degree of responsiveness across all three diagnostic categories. DiscussionThe children with TIS had lower physical domain scores and higher caregiver burden scores than healthy children. However, the scores in psychosocial domains were similar to those in healthy children. Since responsiveness of the CHQ was small, it can be con-cluded that our study demonstrates the lack of ability in the questionnaire to reflect clini-cally important minimal changes in response to the VEPTR instrumentation in this popu-lation. Therefore, a Disease Specific Instrument (DSI) may be needed in order to detect the minimal changes in this population. Current efforts are on their way to better under-stand the clinical features that have the most profound effects on the life of these children and to develop a DSI for this population.

Paper #15

Surgical Complications in Early Onset Scoliosis

Jonathan H. Phillips , M.D. , D. Raymond Knapp, Jr., M.D., Jose Herrera-Soto, M.D.

Between March 2002 and July 2005 a total of 44 surgical procedures were performed in 20 young scoliosis patients involving the use of unfused instrumentation. Average age was 8 years-1 month, range 2 + 3 to 12 + 7. Total number of procedures was 44, average 2.2. and only one patient has gone on to definitive fusion at this point. This indicates the early stage of development of this program at our center. All patients received either ISOLA growing rod instrumentation or VEPTR. There was a 100% complication rate in the VEPTR patients and 64% in the growing rods. 20% of total complications occurred in patients who moved to our area from out of state and were established complications, sometimes after multiple surgeries done elsewhere. Our local complication rate was 45% which is nearly identical to published literature (Akbarnia, BA, et al 2005). There was an alarmingly high rate of deep infection which occurred early in the VEPTR group and late after many lengthenings in the growing rod group. Of 9 infections, implants were sal-vaged in only 2 cases. The others all need to be removed and definitive treatment of the scoliosis is still pending. There was 1 perioperative death in the group. There was one transient intraoperative neurological deficit with no permanent loss postoperatively. A large variety of very rare syndromes comprised much of this group. As in other reports, implant cut out and breakage constituted the majority of non infectious complications. These patients represent a high risk group but seem to have a complication rate in excess of other high risk patients. For example, our group reported an 8% infection rate in defin-itive fusion for neuromuscular scoliosis recently (Phillips et al 2005). Our infection rate for this early onset group was five times greater. It is assumed that the multiple surgeries for rod lengthening lie at the heart of this high complication rate and strategies to avoid repeated open procedures may reduce the rate of infection at least. The fact that 20% of complications were inherited from other centers in the USA underlies the need for a central data bank of this small group of patients to truly delineate outcomes in Early Onset Scoliosis surgery.

Paper #16

Long-term Results of Congenital Scoliosis Treatment

Martin Repko , Martin Krbec, Jan Burda, Jan Pesek, Richard Chaloupka, Vladimir Tichy

AimThe aim of our study is to evaluate clinical and X-ray long-term results of congenital sco-liosis treatment.MaterialThe total number of 442 patients with congenital scoliosis treated in our department in the period from 1976 to 2006 was retrospectively evaluated. There were 175 (40%) pa-tients treated by conservative manner, 64 (14%) pts. were treated by single bone fusion, 141 (32%) pts. were treated by correction with instrumentation using the posterior ap-proach and 62 (14%) pts. were treated by combined anterior/posterior surgical approach. An average follow up was 16 years and 3 month. Results1. conservative treatment - the magnitude of the curves was at time of detection on aver-age 44,1° according to Cobb angle and 39,8 at time of last control.2. single bone fusion by posterior surgical approach - an average time of surgery was 6,6 years, follow up was 14,2 years. The magnitude of the curves was at time of detection on average 44,1°, 44,2 preoperatively, 34,4 postoperatively and 38,4 at time of last control. There were no neurological complication. 3. posterior surgical approach with instrumentation - the time of surgery was 8,6 years, follow up was 12,6 years. The magnitude of the curves was at time of detection on aver-age 61,1°, 66,8 preoperatively, 40,9 postoperatively and 46,0 at time of last control. There were 1,7% of neurological complications. 4. combined anterior/posterior surgical approach with hemivertebrectomy and instrumen-tation - the time of surgery was 11,2 years, follow up was 17,9 years. The magnitude of the curves was at time of detection on average 52,2°, 64,9 preoperatively, 38,3 postopera-tively and 39,0 at time of last control. There were 1,2% of neurological complications.Discussion and ConclusionsEarly detection, good timing and choosing of adequate surgical treatment type are the main factors of quality treatment results. All methods of surgical treatment led to the im-provement in magnitude of the scoliotic curve. The best method seems combined ante-rior/posterior surgical approach with hemivertebrectomy and instrumentation stabiliza-tion.

Paper #17

VEPTR in Patients with a Previous Spinal Fusion

Peter Sturm, M.D ., John M. Flynn, M.D., Randal R. Betz, M.D., John T. Smith, M.D., John B. Emans, M.D., Sohrab Gollogly, Robert M. Campbell, M.D., Melissa P. Smart, BS, R.N.

IntroductionSpinal fusion had been the mainstay of treatment for children with complex congenital scoliosis. This treatment had an unintended deleterious effect on spinal growth and pul-monary development. The use of the VEPTR in these patients has been shown to control curve progression while allowing for trunk growth and further lung maturation. This study looks at the use of a VEPTR in patients who had undergone a spinal fusion. MethodsSeventeen patients who had previous spinal fusions, and then subsequently underwent the insertion of a VEPTR between September 1996 and February 2003, were identified among patients entered prospectively into a database for an FDA IDE study. Pre and postoperative Cobb angle, thoracic height and complications were recorded. Eight to twelve month follow up data was available for 12 patients and 36 month follow up in 7. ResultsThe indication for VEPTR in these patients was a progressive curve despite previous fu-sion, and persistent thoracic insufficiency. Average age at VEPTR insertion was 6 years and 7 months. Average preoperative Cobb angle was 59° (range 10 - 95°). Average postoperative curve measured 49° (range 5 - 80°). In the subgroup with one year follow up the average preoperative Cobb angle was 58.3°, postop 41.6°, follow up 48.7°. The average change in trunk height was 0.74 cm at index surgery. 7 patients had complica-tions. This included 3 patients with loss of fixation alone, 1 patient with a postoperative infection, 2 patients with both an infection and loss of fixation, and 1 patient with postop-erative Horner’s syndrome.ConclusionThe use of a VEPTR has been shown to be beneficial in children with thoracic insuffi-ciency due to various etiologies. In patients who have already had a spinal fusion the goals of VEPTR implantation are to improve truck deformity, expand the chest, and mod-ulate the spinal deformity when possible. The amount of correction of both the Cobb an-gle and thoracic height is less than in chlidren who have not undergone a prior spinal pro-cedure. In addition, the complication rate is higher. It should be viewed as a salvage pro-cedure in this group of patients.

Paper #18

Short Anterior Instrumented Fusion of Lateral Hemivertebra

Enrique Garrido, MRCS, EBOT , F. Tome, SK Tucker, TR Morley, HNM Noordeen

Study DesignRetrospective study with clinical and radiological evaluation of 29 patients with congeni-tal scoliosis who underwent 31 short segment anterior instrumented fusions of lateral hemivertebrae.ObjectiveTo evaluate the safety and efficacy of early surgical anterior instrumented fusion with partial preservation of the body of the HV in the treatment of progressive congenital scol-iosis in children below the age of 6.Summary of Background DataA variety of treatments have been described in the literature for the treatment of HV. We report the results of a novel technique.Materials and MethodsBetween 1996 and 2005, 29 consecutive patients with 31 lateral HV and progressive scol-iosis underwent short segment anterior instrumented fusion with partial preservation of the body of HV. Additional posterior Moe fusion was performed on 29 HV. Mean age at surgery was 2.9 years. Mean follow-up period was 6.2 years.ResultsPreoperative segmental Cobb angle averaging 39, was corrected to 15 after surgery, being 16° at the last follow up (56,4% of improvement). Compensatory cranial and caudal curves corrected by 50% and did not change significantly on follow up. The angle of seg-mental kyphosis averaged 14 before surgery, 13 after surgery, and 14° at follow up. Coronal and sagital balance improved postoperatively and gradually during follow up to normal values. 10 patients had a thoracic kyphosis and two patients a lumbar lordosis be-low average for their age. There were 2 posterior wound infections requiring surgical de-bridment, one intraoperative fracture of the vertebral body during screw insertion and in one case there was loss of correction due to implant failure. All went on to stable bony union. There were no neurologic complications and no additional operations. ConclusionsEarly diagnosis and early and aggressive surgical treatment are mandatory for a success-ful treatment of congenital scoliosis and to prevent the development of secondary com-pensatory deformities. Anterior instrumentation is a safe and effective technique capable of transmitting a high amount of convex compression allowing short segment fusion which is of great importance in the growing spine

Paper #19

Prior Instrumentation and Fusion Method at the Anchor Sites

Tomoaki Kitagawa, M.D., Hiroshi Taneichi, Daisaku Takeuchi, Takashi Namikawa, Satoshi Inami, Tetsuro Kiya, Yutaka Nakamura, Takahiro Iida, Yutaka Nohara

BackgroundGrowing rods system is usually used for early onset scoliosis that have small and fragile posterior elements due to not only its young age but also congenital or genetic factors, which make it difficult to apply strong corrective force at the time of initial surgery and/or necessitate post-operative immobilization using cast or orthosis.MethodTo prevent this problem, we have developed a staged operation to apply growing rods. At the initial surgery, only the proximal and distal anchor sites are exposed and the patients undergo one- or two-level instrumentation and fusion at the both sites. Instrumentation includes either hooks, pedicle screws, or their combination. Fusion procedure includes decortication of the lamina and facet joint, and local bone grafting. The second surgery will be planned after the fusion mass becomes mature and solid, usually about three months after initial surgery. The anchor sites will be exposed again and previous screws and hooks will be replaced with thicker ones if necessary. Four cases of this method were investigated retrospectively. The age at the surgery ranged from three to eight years old. The primary diagnosis includes Turner syndrome, neurofibromatosis, Ehlers-Danlos syn-drome, and scoliosis associated with CHARGE syndrome. ResultsMean pre-operative Cobb angle of the major curve is 112°, ranging from 48 to 143°. Mean post-operative Cobb angle after correction surgery using growing rods was 46°, ranging from 27 to 63°. Mean operation time was 202 minutes at the first surgery and 173 minutes at the second surgery. The laminae were covered with solid fusion mass and pedicle walls were thickened and expanded at the second surgery, so stronger anchors could be obtained. Then growing rods were applied and strong corrective force could be applied to achieve enough initial correction. Patients were allowed to walk within three days after surgery without use of cast or orthosis. Correction loss did not happened until next rods lengthening surgery.ConclusionPrior instrumentation and fusion method for growing rods is effective for strong initial correction and can avoid failure of the posterior element of the spine.

Paper #20

Evaluation of Vertebral Anomalies and Vertebral Osteotomy

Noriaki Kawakami, M.D ., Taichi Tsuji, Kazuyoshi Miyasaka, Tetsuya Ohara, Yasunori Tatara, Kei Ando, Ayato Nohara

Posterior hemivertebrectomy has been reported as effective, safe, and less invasive for the surgical treatment of hemivertebrae; although it is technically demanding. However, the combined anterior and posterior operation is still useful and may be selected for some types of congenital vertebral anomaly.PurposeThe purpose of this study was to assess the type of congenital vertebral anomaly and the operative strategy using vertebral osteotomy and to determine which types of vertebral anomaly should be treated through an the combined anterior and posterior approach.Materials and MethodSixty patients who underwent vertebral osteotomy for congenital vertebral anomaly were evaluated retrospectively. They consisted of 31 males and 29 females and the average age at the time of operation was 13 years. One patient underwent two separate operations for discrete, distinct anomalies. Of 61 operations in total, 36 used the posterior approach and 25 used the combined anterior and posterior approach. Of 25 combined anterior and pos-terior operations, 7 were two-staged. The overall postoperative follow-up time was 55 months (17-156).ResultsThe types of congenital vertebral anomaly were evaluated using 3DCT and were classi-fied into 16 cases of solitary simple, 24 of multiple simple, 16 of multiple complex, and 4 of segmentation failure. The reasons for selection of the combined anterior and posterior operation included the release and/or osteotomy of multiple levels in 11 cases, leaning curve in 7, and additional anterior bone graft for a big gap in the osteotomy site in 6 cases. In 36 patients in whom the posterior approach was utilized, 29 (80%) were in-cluded in solitary simple or multiple simple, which indicated anterior and posterior uni-son type anomalies. Scoliosis was corrected from 43.2° to 16.1° using the posterior ap-proach only, and from 72.6° to 33.1° with the combined anterior and posterior operation, indicating statistically significant differences for both preoperative and postoperative curve magnitudes.ConclusionMore severe curves and multiple congenital vertebral anomaly may be factors that neces-sitate the combined anterior and posterior operation.

Paper #21

PRSS in Management of Adolescent and Juvenile Scoliosis

Qibin Ye

ObjectiveTo study on the therapeutic mechanism of an innovated instrumentation-Plate-Rod Sys-tem for scoliosis (PRSS) and its effectiveness for the surgical management of adolescent and juvenile scoliosisMethodTo avoid the necessity of repeated operative instrumentation lengthening, a new device-PRSS was developed in our department. Since October 1998, a total of 183 scoliotic chil-dren were treated using PRSS. Among them, 66 cases adolescent and 23 cases juvenile scoliosis were evaluated prospectively. The mean age at the time of surgery was 12.15 years in adolescent group and 7.98 years in juvenile group. The experimental study on type X collagen which reflect cartilage degeneration was studied in PRSS-instrumented animal spine to express the therapeutic biomechanism .ResultsThe preoperative scoliotic curve was 66.58° and post-operative curve was 22.70° (68.86% ) in adolescent group and in juvenile group, the scoliotic curve was improved from 80.7° to 30.5° (62.2%). An average of 11.13mm spinal lengthening of the instru-mented segments was achieved in adolescent group and 13.38mm in juvenile group. In 10 cases, the implant was removed after bone maturing was reached. The spine keep good maintained of correction and essential normal flexibility. When PRSS is placed in place, compressive stress was found to exert on the convex side, while tensile stress on the concave side of the curvature, and more type X collagen to be expressed on convex side than concave side, it suggest that compressive stress leads to increase earlier carti-lage degeneration of end plate in convex side, so as to retard the growth of the end plate of this side, resulting in maximum spinal realignment. ConclusionThe PRSS, which dispenses with spinal fusion and allows extension along with the chil-dren growth, is able to provide and maintain desirable correction of scoliosis in one stage operation and it is helpful to prevent Crankshaft phenomenon, essential normal spinal flexibility can be obtained after treatment. This new device is an effective instrumenta-tion for correcting scoliosis, especially in growing children.

Paper #22

Spinal Hemiepiphysiodesis Correlates with Structural Changes

Eric Wall, M.D ., Donita I. Bylski-Austrow, Ph.D, David L. Glos, BSE, Edgar T. Ballard, M.D., Andrea Montgomery, BS, Alvin H. Crawford, M.D.

IntroductionSome stapling methods have been shown to alter spine alignment in preclinical models. In long bones, staples have been shown to alter growth plate structure particularly in the hypertrophic zone. In the spine, however, stresses transmitted to the physes are likely af-fected by the intervertebral disc. The purpose of this study was to determine if structural changes to the vertebral growth plate accompanied increased spine curvatures in a porcine model of spinal hemiepiphysiodesis. The hypotheses were that the height of the hypertrophic zone and size of hypertrophic cells were lower at the stapled levels and side compared to both an unoperated level and the contralateral side. MethodsAnatomically-based spine staples were implanted endoscopically into the left side of 6 mid-thoracic vertebrae of five skeletally immature domestic pigs. Each staple was cen-tered over an intervertebral disc and two growth plates, with placement aided by a guide-wire. After 8 weeks, spines were harvested. Mid-coronal sections were prepared for his-tologic analysis. Hypertrophic zone height, height and width of hypertrophic cells, and disc height were measured at discrete sampling locations across the plane at stapled and unstapled levels.ResultsZone height, cell height, and cell width were lowest on the stapled side of the stapled level, with significant differences in the overall statistical model (p≤0.02). Disc heights were reduced at the stapled levels across the coronal plane.ConclusionsA staple-like implant and particular endoscopic insertion procedures were associated with gradually decreased growth plate height and cell size, as well as decreased disc height.Clinical RelevanceThis is the first report of spinal hemiepiphysiodesis using clinically relevant procedures that has been shown to affect the growth plate asymmetrically. The results indicate that some devices may be capable of slowing progression of a developing scoliotic curve by differential growth inhibition.

E-Posters

E-Poster #1

Efficacy of Growing Rods in Infantile Marfans Scoliosis

Paul D. Sponseller, M.D ., George H. Thompson, M.D., Behrooz A. Akbarnia, M.D., Marc A. Asher, M.D., John B. Emans, M.D., Tina Chen, BS, Connie Poe-Kochert, RN, CNP

This is a retrospective analysis of nine patients with Marfan Syndrome and scoliosis (de-veloping before age 3) treated with growing rod techniques with a minimum of 2 years follow-up. Radiographic and chart reviews included the following parameters: age, lordo-sis, kyphosis, complications, coronal balance, T1-S1 length, and initial curve angle. Three patients had single and 6 had dual growing rods. Age at initial surgery was 4.5 years (2-9). Mean scoliosis curve was 80° (54-105) and thoracolumbar kyphosis was 56° (27-85) preoperatively. Patients on Coumadin were lengthened yearly or throughout longer intervals of time. The mean follow up was 65 months. Four of 9 patients have un-dergone final fusion. The common construct was T2/4 to L4 in 4 patients and or to the pelvis in 4. Curve correction was 54% (41% with single rods, 61% with dual rods). Mean coronal imbalance improved from 56 to 18mm and sagittal imbalance from 31 to 21mm. Increase in T1-S1 length over the treatment period was 10.2cm for the whole group and 13.3cm for those who underwent final fusion. Complications included two rod breakages and two intra-operative dural leaks. There was one anchor dislodgement, however no postoperative dural leaks. None of the patients developed clinically significant junctional kyphosis. One patient died of unrelated causes three months postoperatively. Growing rod techniques can prevent large infantile curves from becoming severe in patients with Marfan Syndrome. Dual rods were more corrective compared to single rods. Significant spinal length can be obtained to minimize trunk disproportion.

E-Poster # 2

The VEPTR "Parasol" Expansion Thoracoplasty for Treatment of Transverse Volume Depletion Deformity of the Convex Hemithorax Rib Hump in Early Onset Scoliosis

Robert M. Campbell, M.D ., JT Woody Smith, JW Simmons, S. Inscore, BR Cofer, JJ Doski, C. Grohman

Cobb angle correction and improved SAL is common with VEPTR treatment, but windswept deformity narrows the room for the lung contained within the rib hump. The structural basis of rib hump is usually not acute angulation of the rib, but a spine rotation-driven deviation of the ribs. Each rib “bucket handle” folds downward, closing shut the convex hemi-thorax, resembling the closure of a parasol. To reverse the mechanism of this deformity, a VEPTR expansion thoracoplasty was developed, termed the “parasol” procedure. Multiple levels of intercostal muscle are lysed to mobilize the depressed chest wall. Rib segments are elevated upward and outward, then stabilized in the “open para-sol” position.Methods10 pts. Avg f/u of 6 yrs from initial concave surgery and 4 yrs from convex parasol pro-cedure. 7 pts 70 mm radius VEPTR, 4 pts hybrid/rib-rib VEPTR ResultsCobb angle pre-op 79°, pre-convex proc 51°, 49° at f/u. SAL 1.5 pre-op, 0.92 at f/u. Con-cave/convex hemithorax width ratio was 2.79 pre-concave implant, 3.07 pre-convex im-plant, and 2.17 f/u. CT lung volumes (n = 6): pre-implant convex/concave l.v. ratio was 0.87, 0.91 at f/u. Avg. vital capacity at f/u was 37.8% predicted (n=9). Pt complications: (4) spinal hook migration, (3) superior migration rib cradles, (1) fractured hybrid, (1) tita-nium sling migration, (3) infection, (3) skin slough, (2) pneumonia.ConclusionExpansion of the rib hump in early onset scoliosis by the VEPTR “parasol” procedure in-creases the lateral width of the hemithorax on radiograph. Some improvement in the con-vex/concave lung volume ratio is seen. Scoliosis is not increased by the convex distrac-tion. The complication rate is frequent, but treatable. SignificanceThe loss of transverse volume in the convex hemithorax due to rib hump of the pt with EOS contributes to TIS. The VEPTR “parasol” expansion thoracoplasty directly ad-dresses the anatomic deformity of rib hump, probably partially reversing the convex vol-ume depletion problem. If done early in life, this may help encourage convex lung growth. For any growing pt with rib hump, especially if vital capacity is low, the “para-sol” procedure should be considered instead of a traditional orthopaedic thoracoplasty.

E-Poster #3

Anterior Instrumented Correction of Congenital Scoliosis

Hazem Elsebaie, M.D., Yasser Elmaelligy, FRCS, M.D., Wael Koptan, M.D., Mootaz Salaheldine, MSc, Hilali Noordeen, FRCS Orth

Study DesignRetrospective analysis. ObjectivesTo determine the safety and efficacy of this technique in the management of progressive congenital spinal deformities due to failure of formation analyzing: correction of spinal deformity, fusion rate and incidence of complications. Summary of Background DataSeveral modalities have been reported for the treatment of young children with congenital spinal deformities including the recent reports on hemivertebrectomy with instrumenta-tion. There has always been concerns regarding epidural bleeding, neurological complica-tions, pedicle screws placement, implant faillure and prominence of posterior constructs in this very young age group. Anterior release, decancellation of the hemivertebra with-out opening the spinal canal and anterior instrumentation offers a new alternative which can avoid these concerns.MethodsA total of 11 patients with progressive congenital spinal deformities due to failure of for-mation who had single stage anterior instrumented fusion, decancellation of the hemiver-tebra and posterior non instrumented fusion followed for a minimum of 2 years were ana-lyzed. All patients had single hemivertebra. The average age of the patients was 2 years 7 months (1y 9m to 3y 10 m). And the average follow up period was 3 years 1 months (2ys to 4ys 5m). ResultsThe mean scoliosis angle improved from 48° (34-58) preoperative to 17 (11-25) at the fi-nal follow up, a mean correction rate of 64.5% , the angle of kyphosis was 20° before surgery and 11° at the final follow up a mean correction of 45%, all the patients having radiological fusion. The average operative time was 120 mins (98-180 min). There was one superficial infection. ConclusionAnterior instrumentation with decancellation of the hemivertebra a offers a safe and ef-fective alternative to hemivertebrectomy with less risks and less operative time and blood loss with an equal amount of correction, making the need of the more aggressive hemivertebrectomy questionable in this very young age group.SignificanceWith anterior instrumentation decancellation of the hemivertebra is safer and simpler than hemivertebrectomy with same effectiveness in the very young children.

E-Poster #4

Spinal Open-Wedge Osteotomy

Dezso J. Jeszenszky, M.D., Tamas Fulop Fekete, Martin Sutter, Friederike Lattig, An-dreas Eggspuhler, Frank S. Kleinstuck

IntroductionCorrection of congenital scoliosis is usually achieved by in situ fusion or by shortening of the spine. Intraoperative distraction may cause neurological damage and is therefore usu-ally avoided or is performed indirectly by slowly distracting the ribcage. A surgical method to correct spinal deformity by osteotomy and distraction in congenital scoliosis has not been reported before.Methods3 patients treated for mixed congenital scoliosis were studied. The surgical procedure in-volved concave side exposure of the bar to the anterior aspect using a posterior approach. The surgeon performed a near circumferential osteotomy around the dural sack and then opened up the osteotomized segment to correct the curve. The correction was augmented through distraction under continuous intraoperative spinal cord monitoring. Stabilization was performed without fusion and on one side only, with pedicle screws, rods and rib hooks. The Cobb angles of scoliosis were measured pre- and postoperatively.ResultsAge at surgery was 4.0 (2.4 – 5.25) years. Follow-up time was 1.52 (0.5 – 2.92) years.The avg scoliotic curve was 60.7° (50 – 69) pre-implant, 29.3° (18 – 40) post-implant, yielding a correction of 31.4° (51.8%). The pre- and postoperative compensatory curves were 34° (31-56) and 17° (12-23), respectively. Multimodal monitoring of the spinal cord during surgery revealed potential damage of the spinal cord in two cases immediately fol-lowing the correction. Therefore the final correction was delayed for one week in both cases. No postop neurological complication was detected.ConclusionSpinal open-wedge osteotomy is an effective surgical technique for correction of congen-ital scoliosis. Surgery is performed only at the congenitally affected region of the spine. Goal of surgery is to achieve the greatest correction possible, at this site. All other healthy regions (secondary curves, convex side) of the spine are left intact. The surgery should be performed as early as possible, so all the intact spinal regions can grow nor-mally. The use of intraoperative spinal cord monitoring is essential.

E-Poster #5

The Influence of Fixation Rigidity on Intervertebral Joints

Charles-H Rivard, M.D ., Christine Coillard, M.D., Gary L. Lowery, M.D., Souad Rhalmi, M.Sc., Marco Berard, M.D.

ObjectivesThe study was to determine whether allowing intervertebral micromotion compared to the effect of the rigidity of immobilization on the biological changes in the intervertebral joints.. The OrthobiomTM was developed and used as instrumentation in comparison with a rigid system and a control group.MethodsTwenty growing Yucatan minipigs were divided into 4 groups. Six were fixed with a rigid system. Eleven were fixed with a mobile unconstrained implant (OrthobiomTM) that allowed intervertebral micromotion. Three minipigs were used as control. They were euthanized and underwent the same necropsy. X-ray follow-ups were taken to provide information about the fixation of the mobile and rigid system. In addition, a CT scan was performed on a control, rigid and mobile minipigs.Results In the rigid group, despite the growth, the length of the instrumented segment remained unchanged. Initial scoliosis of 31° was maintained at 27° (p= 0.37, paired t test). In the mobile fixation group, the length of the instrumented segment grew from 25.3 cm to 30 cm (p=0.0004, paired t-test). The scoliotic curve of 19° was maintained at 17° (p=0.21, paired t-test). CT scans of a minipig instrumented with the rigid system showed sponta-neous fusion within the instrumented section. The CT scans of the minipig with the mo-bile fixation performed after the removal of the implant showed the posterior joints to be well maintained with the preservation of the joints space, and a clearly visible radiolucent line. The discs viability was maintained with the mobile fixation and degenerated with the rigid one.ConclusionsIntersegmental micromotion using flexible unconstrained internal system could preserve the viability of the intervertebral joints incorporated within the instrumented section while maintaining reasonably stable fixation in young pigs during growth. This new ap-proach may be a valuable option to fusions, though it needs to be proven effective in hu-mans.

E-Poster #6

Nutritional Improvement Following VEPTR Surgery in Children with Thoracic Insuffi-ciency Syndrome

David L. Skaggs, M.D ., Josh Albrektson, Tishya Wren, Robert M. Campbell, M.D.

IntroductionYoung children with thoracic insufficiency syndrome (TIS) secondary to spinal and/or thoracic deformity are often characterized by a failure to thrive. Nutritional depletion oc-curs in part as the work of breathing approaches the nutritional gain of eating.MethodsA total of 79 patients at 7 different institutions underwent placement of VEPTR devices for treatment or prevention of TIS. All patients underwent weight measurements pre-op and post-op. Patients had a mean age at surgery of 44 months (+/- 33) with an average follow up of 45 months (+/-16, minimum f/u 24 months). All weights were converted to normative percentiles based on the patient’s age.ResultsThere was a significant increase in the mean percentile of patients’ weights relative to normative values (p=0.002). Of the 79 patients, 62 (78%) were <5 percentile in weight pre-operatively. Of these most nutrionally depleted patients 35% (22/62) showed a mea-sureable increase in percentile weight following VEPTR surgery. Of patients not showing an improvement, a change in percentile weight may have occurred, but would not be rec-ognized due to the basement effect of normative percentiles. Of the 17 patients who were >5 percentile weight pre-operatively, 76% (13/17) showed measurable improvement in weight percentiles. ConclusionChildren with TIS undergoing VEPTR surgery have very poor nutritional status, with 78% of patients being <5 percentile in weight. This study documents an improvement in the nutritional status of children with TIS following VEPTR surgery, which is a critically important outcome measure in this population. Children who have better nutrition pre-op-eratively (>5 percentile weight) demonstrate larger gains following VEPTR surgery than those < 5 percentile.

E-Poster #7

Outcomes in the Early Treatment of Progressive Infantile Scoliosis

Ascani Elio, Ramieri Alessandro, M.D.

Infantile scoliosis, idiopathic, congenital or neurophatic, show common characteristics for gravity and rapid worsening. Their treatment is still controversial, with different choices among the spinal surgeons. We present the long-term results (mean F.U. 13 yrs; range 16-30) of a retrospective series of 43 progressive infantile scoliosis with different etiology, treated from 1975 to1990. Conservative treatment consisted in brace or cast im-mobilization. Halo-traction was also applied. Initial surgical approach was achieved by anterior hemiepiphysiodes and posterior hemiarthrodesis (n=4), posterior epiphysiodesis (n=7), hemivertebra excision with or w/o instrumentation (n=12), Ascani-Zielke subcu-taneous rod (n=12), early posterior fusion with pediatric instrumentation (n=8). Trying to define the best procedure in the management of severe spinal deformity in young chil-dren, our results with conservative treatment were unsatisfactory due to curve progres-sion. Posterior-anterior hemiepiphysiodes achieved an acceptable stabilization of the con-genital curves before the final fusion (n=4), while no significant difference between hemivertebra resection techniques was detected. Posterior epiphysiodes was more effec-tive for kyphoscoliosis. Ascani-Zielke rods generally obtained correction, showing never-theless mechanical (n=4) or general complications (n=3). Early instrumented fusion ob-tained the improvement and stabilization of the deformity, except for a case of initial crankshaft, re-operated by an anterior arthrodesis.Our experience in the early treatment of infantile scoliosis recommends a surgical ap-proach. Hemiepiphysiodes, circumferential procedures or growing rod techniques may be safe and effective if correctly applied. Nevertheless, also definitive instrumented spinal fusion at a young age can be judged as valid unique solution for these complex deformi-ties.

E-Poster #8

Surgery Before Age 3 in Patients with Congenital and Syndromic Scoliosis Followed Un-til the End of Growth

Charles D'Amato , M.D.

PurposePatients with progressive congenital and syndromic scoliosis have in the past been treated with spinal fusion at an early age to prevent progression. The effects of spinal surgery on pulmonary development and function are still under investigation. Recent reports have shown diminished pulmonary function in patients who have undergone fusion of the tho-racic spine at an early age occasionally leading to pulmonary hypertension, cor pul-monale and, eventually, death. The aim of this retrospective study is to investigate how early spinal arthrodesis (before age 3 years) affects the pulmonary function and the growth of the thorax in patients followed to skeletal maturity.Material and MethodsSix patients with congenital scoliosis and three with early onset scoliosis were surgically treated before age 3. The average age at initial surgery was 20 months (range: 12 to 39 months). Six patients were treated with a posterior spinal fusion and three had anterior and posterior surgery. Instrumentation was used in only one patient. Six was the average number of thoracic segments fused (range: 2 to 12). Final standing height (STH) and trunk height (TRh) were measured in all patients. Using standard radiographs thoracic spine height (Th), lumbar spine height (Lh), pelvic width (PW) and chest width (CW) were measured in all patientsª. Vital Capacity (VC), Forced Expiratory Volume in 1 sec. (FEV1), Max. Mid Exp. Flow rate (FEV25-75), Residual Volume (RV) and Total Lung Capacity (TL) were available for four patients. The average follow up was over 14 years.ResultsSTH, TRh, Th were significantly reduced in all patients but one who had fusion of only two thoracic vertebrae. Lh was normal. The observed thoracic dimensionsª were signifi-cantly reduced compared to the expected ones in all patients but one who had only two thoracic spine levels fused. Average VC was 1.98 L and 67% of predicted values (range: 1.27-2.96), average FEV1 was 1.69 L and 62% of predicted values (range: 1.04-2.42), av-erage FEV25-75 was 1.73 L/min. and 56% of predicted values (range: 1.04-2.23), aver-age TL was 0.85 L and 69% of predicted values (range: 0.73-0.97).ConclusionPatients undergoing thoracic fusion for spinal deformity scoliosis before age three have significantly reduced TRh, Th and chest dimensions. Early thoracic spine surgery inhibits the growth and function of the thorax. The number of thoracic vertebrae fused seems to be related to the severity of the pulmonary impairment.ªEmans JB and coll. Prediction of thoracic dimensions and spine length based on individ-ual pelvic dimensions in children and adolescents. Spine 2005;30(24):2824-2829

E-Poster #9

Unilateral Unsegmented Bars, Do They Grow with Distraction?

Hazem Elsebaie, M.D., David L. Skaggs, M.D., Behrooz A. Akbarnia, M.D.

Study DesignRetrospective analysis of 3 patients with congenital unilateral thoracic unsegmented bar treated with distraction implants with a minimum of 2 years follow-up. ObjectivesTo determine the ability of unilateral bars to grow, quantify this growth and the amount of local coronal angle correction of the unilateral bar by concave side distraction.Summary of Background DataUnilateral bars are identified as having absolutely no growth potential, it has always been assumed that the concave sides of the congenital curve do not grow. A recent study by Campbell and Hell-Vocke showed that unilateral bars placed under tension by a rib pros-thesis showed an increase in length of the bar. This finding has been questioned and not repeated to MethodsThree patients with progressive congenital spinal deformities due to unilateral thoracic bar treated by distraction implants were analyzed. ResultsFirst patient, a 7y 8 m old girl treated with single concave growing rod followed for 2+6 years and had 5 distractions. The cobb angle (measured at both ends of the bar) improved from 48 post initial surgery to 38 at the latest follow up (correction of 20.8%), the bar in-creased 5mm in length an increase of 16.6% of the original length of the bar The second patient, a 9y 1m old girl treated with single concave growing rod followed for 2 years and had 5 distractions. The Cobb angle improved from 40.5 post initial to 29 at the latest fol-low up (correction of 28.5%), the bar increased 4mm in length an increase of (12.5% of the bar) The third patient, a 2y 3m old girl treated with VEPTR followed for 5 y 1m and had 7 distractions. The cobb angle remained almost unchanged and the bar increased 6mm in length an increase of (28.5 % of the bar) ConclusionThe unilateral bars seem to grow under concave vertebral distraction; their growth is much slower than the normal vertebrae under the same circumstances (around 25%) The coronal Cobb angle of the unsegmented bar was also improved significantly in patients treated with concave growing rod.

E-Poster #10

Continued Spinal Growth in Early Onset (Juvenille) Idiopathic Scoliosis

Lynn Letko, M.D., Rubens Jensen, M.D.

IntroductionThe treatment of early onset (juvenile) idiopathic scoliosis remains a challenge for spinal deformity surgeons. The goal of treatment is to control an often rapidly progressing de-formity while continuing to allow for an increase in spinal growth. We present a tech-nique of single rod pedicle screw instrumentation without fusion as a treatment alterna-tive to allow for continued spinal growth until time of definitive fusion.Operative TechniqueThe spine is prepared unilaterally using a scissor or scalpel staying above the periosteum. The pedicle screws are placed in the area to be instrumented but not fused. A rod is then placed and the correction is undertaken. The incision is closed. No brace treatment is re-quired. The patient is followed closely. Pre-operatively, it is discussed with the parents that the patient will require multiple lengthenings and/or exchange to larger diameter screw and rods with growth prior to a definitive fusion.Case Study4 year 7 mo. old patient with EOIS . At the time of the first surgery (4.05) , 106 cm tall. The right thoracic curve measured 37° T6 toT11 ( bending correction to 14°). The left lumbar curve measured 35° T12 to L3 (bending correction to 17°).The patient underwent right dorsal instrumentation T11 to L3 with correction of the thoracic curve to 15° and the lumbar curve to 15°. The correction was maintained until the rod broke in December 2006. The patient was re-instrumented to T8 in 6.07. At the time of revision surgery, the patient measured 124.5 cm . The curves measured 20° T5 to T11 and 23° T12 to L3 pre-operatively The curves measured 20° and 15° respectively post-opera-tively with 30° thoracic kyphosis and 40° lumbar lordosis.ConclusionsUnilateral pedicle screw instrumentation without fusion allows for excellent correction of the spinal deformity and allows for continued spinal growth. Normal thoracic kyphosis and lumbar lordosis may be maintained. The patient is allowed full activity including sports. Close follow-up is required as the instrumentation will need to be lengthened or exchanged prior to definitive spinal fusion.

E-Poster #11

Assessment of Construct Variability Among Experienced Vertical Expandable Prosthetic Titanium Rib (VEPTR) Users

Michale Vitale, M.D ., Jaime Gomez, M.D., Hiroko Matsumoto, MS, Randal Betz, M.D., Robert Campbell, M.D., John Emans, M.D., Jack Flynn, M.D., John Flynn, M.D., Nor-man Ramirez, M.D., Brian Snyder, M.D., Sturm Peter, M.D., Kit Song, M.D. John Smith, Jeffrey Shilt, M.D., David Roye, M.D.

BackgroundSeveral reports have demonstrated remarkable variability in construct patterns for adoles-cent idiopathic scoliosis and adult deformity correction. To this date, the treatment for pa-tients with early onset scoliosis has no algorithm. New treatment options are available such as the vertical expandable prosthetic titanium rib (VEPTR). It is important to iden-tify variability and trends in treatment to guide surgical decisions.MethodsAs part of the discussion of indications and choice of implant, 13 surgeons were given 12 cases with diagnosis of progressive congenital scoliosis and thoracic insufficiency syn-drome, with standard spine radiographs. The reviewers were asked to choose type of treatment, type of construct, construct location and whether or not a thoracotomy should be performed.ResultsIn 8 of the 12 cases all surgeons chose to perform surgical treatments. For each of the re-maining 4 cases only one surgeon decided to treat conservatively with casting/bracing (n=3) or observation (n=1) while the others chose surgical treatments. When the review-ers chose surgery, 76.3% (range 40-100%) matched using the VEPTR. Of these VEPTR users 61.2% (range 0-100%) coincided on using it bilaterally. Agreement on the use of growing rods and fusions was 19.5% (range 0-60%) and 4.2% (range 0-25%) respec-tively. Among all cases agreement on whether instrumentation should extend to the pelvis or not was 70.8% (50-100%). In 5 of 12 cases all surgeons agreed not to perform a thoracotomy. In 3 of the remaining 7 cases a thoracotomy was chosen by only one sur-geon, in another 2 cases only two surgeons did not agree with the rest of the group. In the remaining 2 cases about half of the physicians agreed to perform a thoracotomy.ConclusionThe study found wide variability in choice of construct type, number of constructs and level of instrumentation, however there was a trend in this experienced group of surgeons to a common solution. This was illustrated by the data on thoracotomy where there was less variability and by the agreement that chest wall instrumentation is indicated fre-quently.

E-Poster #12

The Development of Thoracic Hypokyphosis/ Lordosis After Dorsal Hemivertebrae

Lynn Letko, M.D., Rubens Jensen, M.D.

Since 1997, our standard treatment of complex congenital thoracic scoliosis is dorsal hemivertebra resection with or without bar or rib synostosis resection and pedicle screw instrumentation. We report 3 cases which developed thoracic hypokyphosis/ lordosis af-ter this procedure with improvement in the sagittal profile after rod removal.MethodsRetrospective review of 3 patients (3 M) with complex thoracic congenital scoliosis de-formity who underwent dorsal hemivertebrae with or without bar resection with pedicle screw instrumentation between December 1997 and February 2003. Mean age at index surgery was 27 mos (range 19 to 33 mos ). Mean follow-up 74 mos (range 45 to116 mos). Mean number of vertebrae resected was 3 (range 3 to 4). Mean number of seg-ments instrumented was 8 (range 8 to 9) all between T2 and L1.ResultsMean scoliosis pre-op 82° (range 70 to 102°). Mean thoracic kyphosis pre-op 37° (range 22 to 60°). Mean scoliosis post-op 6° (range 0 to13°). Mean thoracic kyphosis post-op 27° (range 20 to 30°). Development of thoracic hypokyphosis/lordosis surgically treated with rod removal a mean of 56 mos after index procedure (range 37 to 92 mos) . Mean kyphosis prior to rod removal was 5° (range minus 5 to10°). Mean kyphosis after rod re-moval was 13° (range 0 to 20°) Mean kyphosis at last follow- up or before rod reinsertion was 21° (range 10 to 32°). Rod reinsertion was indicated in 2 cases of increasing scolio-sis.ConclusionsDorsal hemivertabra resection and pedicle screw instrumentation is provides excellent scoliosis correction in cases of complex thoracic congenital deformity. The posterior pedicle screw instrumentation may act as a tether resulting in the development of hy-pokyphosis /lordosis as the anterior column continues to grow especially in cases of mul-tilevel instrumentation. Rod removal has allowed for improvement of the thoracic sagittal profile (plastic deformation versus growth). Rod reinsertion with the rods bent to match the improved sagittal profile may be necessary in cases of scoliosis progression

E-Poster #13

Growing Rod for Syndromic Scoliosis

Koki Uno, Norihide Sha, Takuya Kimura, Hiroshi Miyamoto, Yoshiyuki Inui, Kou Ta-dokoro, Naoatsu Megumi

Twenty-five syndromic scoliosis treated with growing rods were retrospectively evalu-ated. There were 9 boys and 16 girls and the average age at first operation was 6.7, ranged 1.5 to12 years old and average follow-up was 3.5 years. Pathology included neu-romusucular disease in 4, neurofibromatosis in 3, congenital in 3, bone metabolic disor-der in 6, congenital malformation syndromes with mental retardation in 7, thoracic cage defect in 2. Three were 21 ambulators and 4 non-ambulators. Seven patients were men-tally retarded. The average magnitude of the curve was 95° and 55° after operation and 60° at final follow-up. Proximal foundation was between T1 to T4 and lowest foundation were between L1 to sacrum. One hundred and thirty operations were performed includ-ing initial surgery. The average interval between operations for rod lengthening was 7 months ranging from 5 months to 12 months. Rod lengthening was performed periodi-cally, based on curve progression of 10° for earlier cases. For recent cases, lengthening was performed every 6 months routinely. There were 29 complications. Hook dislodge-ment in 13, deep infection in 3, superficial infection in 2, rod breakage in 4, others in 2. Of the 29 complications, 18 complications out of 50 surgery occurred in boys and 11 out 80 occurred in girls. Fourteen complications occurred in early 5 cases. Four patients were performed final fusion due to skeletal maturity or due to failure of controlling the deformity. One of them suddenly died 2 years after final fusion . Whether patients have mental retardation or not, and were ambulator or not did not influence the result. Growing rod for syndromic scoliosis can be performed with favorable results at this moment com-parimg to those of growing rod for juvenile idiopathic scoliosis.

E-Poster #14

Cell Signaling Pathways Growth of in Mouse Vertebral GP

Chitra Dahia, Eric Mahoney, Atiq Durrani, Christopher Wylie

IntroductionThe objective of this study was to delineate signaling pathways present in postnatal lum-bar vertebral growth plate (LVGP), and their expression pattern during growth and aging. Material and MethodsEight micrometer cryosections in the coronal plane were collected from decalcified lum-bar vertebrae of 1-12 weeks old male FVB mice. Histology was analyzed by H&E. Im-munolocalization of components of the TGFbeta1&2, BMP2,4&7, IHH & FGF2 path-ways was carried out using confocal microscopy. ResultsMembrane localization of IHH & its receptor PTC was observed in proliferative zone chondrocytes until 2-weeks of age. Between 2 and 12 weeks of age, active TGF1&2 sig-naling determined by downstream intermediate (p)Smad2/3 was present at the junction of the proliferative and early hypertrophic zones which disappeared at 9 weeks. Active BMP2, 4&7 signaling determined by their downstream intermediate (p)Smad1/5/8 was found only in the hypertrophic zone chondrocytes at all ages.. FGF2 ligand and activated receptor were found only in the hypertrophic zone chondrocytes of the LVGP of 2-week old mice and decreased with age. ConclusionOur data suggest that IHH signaling is responsible for maintenance of the PZ while TGF beta signaling is involved in the transitioning of the cells from PZ to HZ. TGF beta sig-naling diminishes with age. Absence of TGF beta signaling marks the end of proliferative zone and closure of vertebral growth plate despite the presence of IHH.

E-Poster #15

Three Dimensional Analysis of a New Porcine Model for Scoliosis

Virginie Lafage, Ph.D ., Frank Schwab, M.D., Ashish Patel, M.D., Jean-Pierre Farcy, M.D.

IntroductionSpinal fusion remains the mainstay for surgical treatment of severe/progressive adoles-cent idiopathic scoliosis. However, there is marked interest in non-fusion techniques that may spare mobility of the spine and induce correction through growth modulation. De-velopment of non-fusion techniques requires an animal model with all the attributes of a scoliotic curve: global deformity but also true vertebral dysplasia and axial rotationMethodsThis study included 7 Yorkshire pigs. Scoliosis was surgically initiated through a left pedicle based spinal tether and a left-sided ribcage tethering. Animals were euthanized once they reached severe deformity (≥50° Cobb) or stopped progressing (mean, 12 weeks following procedure). Spines were harvested and CT-scans obtained. Axial CT slices were analyzed to compute vertebral and inter-vertebral height (convex vs. concave) of the apical functional unit as well as the axial rotation of apical/end vertebrae.ResultsMean Cobb angle was 52° (SD 13°). Apical mean axial rotation was 18° (SD 9°) toward the concavity of the curve. Highly significant correlation was found between apical axial rotation and Cobb angle (r=0.959; p≤0.001). Mean axial rotation of vertebrae outside the tether was 1.5° (SD 5°). In terms of vertebral and intervertebral heights of the apical functional unit, no significant differences between anterior and posterior height were found. However, the convex side was always taller than the concave side: 3.7mm (verte-bral), 1.2mm (Disc), differences p≤0.005.Discussion & ConclusionWhile several authors have reported animal studies related to spinal deformity, none have conducted a true 3-D analysis to quantify the dysplasia induced by growth modulation. To our knowledge, this is the first animal scoliosis model reporting a detailed 3-D analy-sis of the deformity. Findings in the porcine scoliosis model are promising and further analysis is in progress to quantify the vertebral deformity (pedicle, body, spinous process). A greater understanding of scoliotic deformity will emerge as will a more rigor-ous analysis of corrective techniques related to growth modulation (ex. fusionless)

E-Poster #16

A Porcine Model for Progressive Scoliotic Deformity

Frank Schwab , M.D., Virginie Lafage, Ph.D., Ashish Patel, M.D., Jean-Pierre Farcy, M.D.

IntroductionOptimal development of non-fusion techniques requires a large animal scoliosis model. Several authors have reported creation of spinal deformity in animals but few of these re-late to large animals. Braun et al. demonstrated scoliosis in a goat model. However there were a number of drawbacks: cyclical breeding, a flattened ribcage, and very severe de-formities. The goal of this study was to develop a reliable porcine scoliosis model, with moderate deformity, amenable to non-fusion device implantation. Materials and MethodsThis IACUC approved study included 14 Yorkshire pigs; 6 of them were part of a pilot study to establish surgical technique. Scoliosis was induced in 8 animals through a left midline ligamentous tethering of the spine, fixated superiorly and inferiorly with pedicle screws, and left-sided ribcage tethering. Progressive deformity was documented with bi-weekly x-rays. Frontal and sagittal curves were measured through the Cobb method, axial rotation was estimated by spinous process deviation (with 0 = midline, -50% = concave lateral border). Animals were observed until severe deformity (≥50°), and then sacrificed.ResultsFailure of progression was noted in 2 animals due to tether rupture. The 6 animals with documented progression were observed during 12 weeks. The mean coronal Cobb angle was 28° immediately post-op and 55° at final follow up. The mean lordosis increased from 9° post op to 23° at final follow up. Apical axial rotation with the posterior vertebral elements into the concavity of the coronal deformity increased from -1.35% post op to -19.76% at last follow upConclusionsThe study establishes a porcine scoliosis model. With placement of a unilateral ligamen-tous tether technique to the spine, combined with concave ribcage ligament tethering, during the rapid growth stage of Yorkshire pigs; a three dimensional spinal deformity can be achieved. The speed of scoliotic deformity leaves significant remaining growth to as-sess growth modulating therapies for correction. This work forms the basis for a number of investigative efforts at developing new fusionless therapies for patients suffering from Adolescent Scoliosis.

E-Poster #17

VEPTR a Two Year Follow Up

Cornelius Wimmer , Peter Wallnoeffer

Since 2004 the treatment with VEPTR is established in Europe. From 2005 to 2007 20 patients were treated with VEPTR. Diagnosis were congenital, neuropathic, and idio-pathic scoliosis. Material and Method. There were 3 congenital, 9 neuropathic, and 8 idiopathic scoliosis. The average age of the 15 female and 5 male patients were 7,5 range from 3 to 13 years. Correction of the pri-mary curve and after lengthening were measured according to Cobb angle before, after and at the follow up. Complications were noted, a patient satisfaction score and lung function were measured. 5 of the 20 patients had had previous surgery.ResultsThe primary curve measured 65° range from 45 to 130 and improved to 32° range from 25 to 75 at index operation. No complications during surgery were noted. The time at op-eration was 125 min. range from 65 to 185. In 15 cases a rib to lumbar spine hyprid was used, and in 5 cases a combination from rib to rib and rib to lumbar spine were used. The blood loos during surgery was in mean 125 ml range from 65 to 180. One patient showed a wound healing, another patient had had a pneumonia, which resolved with adequate therapy. All patient were braced after surgery. The average stay in the hospital was 18 days range from 14 to 31. 15 out of 20 patients had 1 to 3 lengthening procedures. The average correction of the lengthening procedures was 15° 19,8%. In 5 of the patients the second curve must be instrumented. All patients and parents were satisfied with this pro-cedure and would do this procedure again. ConclusionThe first results of the VEPTR instrumentation are encouraging. Remarkable is the low complication rate and the high patient satisfaction.

E-Poster #18

A Cadaver Spine Study of the Effect of Positional Changes on the Accuracy of Manual and Digital Radiographic Measurement of Spinal Landmarks

Robert M. Campbell, M.D., A. Reis, A. Gajjar, L. Cooper

It has been assumed that a six foot tube to x-ray plate distance minimizes beam diver-gence and magnification error for radiographs of the spine, and that digital radiographic measurements are more accurate for measurement than manual, but no study to our knowledge has validated these assumptions. This was studied in a cadaver spine model using 6 foot tube to plate distance with varied distances from posterior spine to plate to simulate obesity, kyphosis, or lordosis. Radiographs were taken at standard tube/plate distance, performed at 2.5cm, 4.5cm, 6.5cm and 8.5cm distances of spine to the plate, measured manually by micrometer and digitally. For spinal lengths there was an avg. 4.3% magnification error rate for manual measurements, and 5.7% for the digitally mea-sured radiographs (p<0.001). The avg. magnification error was 2.7% for the 2.5cm dis-tance radiographs and 7.0% for the 8.5cm group (p<0.001). For the interpedicular dis-tances there was an avg. 3.3% magnification error rate for manual micrometer measure-ment compared to 4.2% for the digitally measured radiographs (p=0.002). The avg. mag-nification error was 1.6% for the 2.5cm distance radiographs and 5.6% for the 8.5cm group (p<0.001). ConclusionManual measurement of radiographic spinal lengths by micrometer is more accurate than digital measurement, but there is still a magnification error of 4.3%. Increasing the dis-tance between spine and plate increases the magnification error. Interpedicular distance measurements also have the same problem with magnification error. SignificanceInvestigators should be aware that measurement of the spine on radiographs, even at 6 ft tube to plate distances, has significant error rates and conclusions about significant growth in length must be interpreted cautiously. While the manual method seems supe-rior, both it and the digital method measure only the virtual image of the spine, not the true dimensions. Increasing the distance of the spine from the plate, either due to obesity, spine kyphosis, or lordosis, probably increases the measurement error. When high spine measurement accuracy is needed, perhaps CT scan analysis would be preferable to radio-graphic measurement.

E-Poster #19

Posterior Surgery of Scoliosis by Hybrid Instrumentation

Costanzo Giuseppe, Ramieri Alessandro, M.D., Barci Vincenzo, M.D.

The effects of a dynamic fixation are due to an increase of the back stability, reduction of disk stresses and the chance of restore the sagittal profile. In scoliotic deformities, the use of shape memory staples in anterior procedures seems promising as also the association of rigid fixation and “dampers” in the junctional areas. The aim of the present study was to assess the effectiveness of hybrid constructs in surgical treatment scoliosis of different etiology. We studied a series of 13 scoliosis of different etiology, both of the growing age and of the adult, treated with mixed back fixation, that is composed by classical rigid seg-mental instrumentation and by “shape memory” elastic interlaminar instrumentation (in compression at the convex side) in nickel-titanium, implanted cephalad or caudad to rigid instrumentation, at the apex of compensation curves (in some cases reducible), with the aim to preserve transition areas. In 11 patients elastic fixation without arthrodesis facili-tated curve stabilization. In 2 patients curve progression less than 10° has been shown. We did not find either instrumentation mobilization or intolerance. At 2 years follow-up, no adjacent level degeneration was found. The advantages offered by rigid segmental fix-ation in scoliosis treatment are well recognized, in relation both to the entity of the ob-tainable correction and to stability, either primary or in a long term basis. Similarly, adja-cent level syndrome may occur above or below the area of arthrodesis. There are interest-ing recent multicentric studies about dynamic or hybrid systems in the treatment of de-generative conditions of the lumbar spine. Applying the principles of “dynamic” vertebral fixation, it is possible to perform hybrid instrumentations by positioning interlaminar “shape memory” staples, in order to preserve transitional areas. Equally, these staples can be implanted on to “cover” compensation curves (often mild and/or reducible in bending) at the convex side, which facilitate compression reduction.

E-Poster #20

Short-term Results of Dual Growing Rod Technique

Yutaka Nakamura , Takahiro Iida, Akihisa Atou, Kanta Tajima, Junya Katayanagi, Satoru Ozeki, Yutaka Nohara

IntroductionSevere spinal deformity in young children often progresses rapidly. Recently we started the dual growing rod technique that was instrumentation with limited arthrodesis only for cranial and caudal anchor points. We report the short term results of six cases that treated in this method. Material and MethodsBetween December 2002 and Jun 2006, dual growing rod technique was performed in six patients. The posterior correction was performed with pediatric ISOLA system. Hooks were used in the two cranial vertebra and pedicle screws were used in the caudal two ver-tebra. Then limited bone graft was performed only for a cranial and caudal anchor part. Rod extension was scheduled once in a half year. Hard brace was applied until bone union was provided. ResultsThe mean Cobb angle was 107° before surgery and 49° after initial correction. We per-formed twenty times of rod extension to maintain spinal growth. There was one compli-cation with instrument breakage. Case 1: Nine-year-old girl (Sotos syndrome) had severe and rapidly progressive scoliosis. Preoperative Cobb angle was 84° in Th4-11. Growing rod was performed from Th4 to 11 with. Cobb angle decreased to 36° after surgery (cor-rection rate; 57.1%). Six months after the first surgery, the rod extension was performed and spinal deformity was maintained to 46°. Case 2: A three-year-old male (Ehlers-Dan-los syndrome) had severe thoracic scoliosis of 143° in Th2-L1. Dual growing rod tech-nique from Th2 to L4 was performed. Postoperative curvature decreased to 82° with cor-rection rate of 42.7%. However, instrumentation failure occurred after surgery. Discus-sionThe dual growing rod technique had good initial correction rate and ability to keep growth spread. In addition, short hard brace periods reduce the mental and physical stress of the patients. We consider this technique is good choice as time saving procedure until final posterior correction and fusion. However, especially in younger patients with bone fragility, additional technique or device is necessary.

E-Poster #21

Controversies in Jarcho- Levin Syndrome

Norman Ramirez , John M. Flynn, M.D., Alberto S. Cornier, M.D., Ph.D., Simon Carlo, M.D., Nigel Price, M.D., Frams Pino, M.D.

Jarcho-Levin syndrome is an eponym that has been used to describe a variety of clinical phenotypes with short trunk dwarfism associated with rib and vertebral anomalies. Re-cently molecular, clinical and radiological data has allowed to further characterize be-tween Spondylothoracic and Spondylocostal dysplasia. IntroductionThis review article will focus on characterizing the differences between Spondylothoracic and Spondylocostal dysplasia and provide a valuable tool for clinical diagnosis and man-agement. MethodsThis is a literature review of all Jarcho-Levin studies.ResultsSpondylothoracic Dysplasia (STD) is a rare pleiotropic genetic disorder with autosomal recessive inheritance. Typical radiological findings include segmentation and formation defects throughout cervical, thoracic and lumbar spine, such as hemi-vertebrae, block vertebrae, and unsegmented bars, with fusion of all the ribs at the costo-vertebral junction (Crab like or fan like configuration) The majority of STD cases previously described in the literature had a poor prognosis due to respiratory complications such as pneumonia, congestive heart failure and pulmonary hypertension( mortality rate 42%) . The gene re-sponsible for this disorder is in the MESP2 gene Spondylocostal Dysostosis (SCD) constitutes a heterogeneous group of patients with au-tosomal recessive and dominant inheritance. They have axial skeletal malformations, in-cluding multiple vertebral segmentation and formation defects and unilateral rib anom-alies. These malformations are typically more prominent in one hemithorax and fre-quently leading to a progressive scoliosis of the thoracic spine due to the tethering effect secondary to the rib anomalies. The majority of cases reported in the medical literature have a good prognosis, due in part to the asymmetry of the thoracic anomalies resulting in a less restrictive thorax. The molecular mutations responsible for the majority of cases of SCD rely on the Dll3 gene on chromosome 19q13. ConclusionJarcho-Levin eponym consists of two distinct pathological conditions. It is essential that this be recognized since the natural history and management of the spinal deformity is completely different.

E-Poster #22

Spinal Fusion with Cotrel-Dubousset Instrumentation for Neuropathic Scoliosis

Marco Teli, M.D., Giuseppe Grave, M.D., Alessior Lovi, M.D., Marco Brayda-Bruno, M.D.

Study DesignRetrospective. ObjectiveTo report on the treatment of patients with cerebral palsy and neuropathic scoliosis with third-generation instrumented spinal fusion by Cotrel-Dubousset instrumentation. Sum-mary of Background DataEvidence is needed to evaluate the increasing use of third-generation instrumented spinal fusion in similar patients. MethodsPatients with cerebral palsy and spinal deformity treated consecutively by 1 surgeon with Cotrel-Dubousset instrumentation and minimum 2-year follow-up were reviewed. An outcome questionnaire was administered at final follow-up. ResultsA total of 60 patients were included. Mean age was 15 years at surgery. Mean follow-up was 79 months. There were 26 anteroposterior and 34 posterior-only procedures. Correc-tion of coronal deformity and pelvic obliquity averaged 60% and 40%, respectively. Ma-jor complications affected 13.5% of patients (implant loosening, deep infection, and pseudarthrosis). Outcome questionnaires showed marked improvements in the areas of satisfaction, function, and quality of life after surgery. ConclusionsSegmental, third-generation instrumented spinal fusion provides lasting correction of spinal deformity and improved quality of life in patients with cerebral palsy and neuro-pathic scoliosis, with a lower pseudarthrosis rate compared to reports on second-genera-tion instrumented spinal fusion.

E-Poster #23

Effect of Removal of NP Cells on the AF of Mouse IVD

Chitra Dahia, Eric Mahoney, Atiq Durrani, Christopher Wylie

IntroductionThe study was designed to analyze the effect of removal of NP cells on the AF in mouse lumbar intervertebral discs (IVD).MethodsThe nucleus pulposus cells were surgically aspirated from L2-3 and L3-4 discs of 2-week old male mice using a 27-gauge syringe. L4-5 disc in the same mouse was sham-operated as control. The effects on the IVD were assayed 2-8 weeks after the surgery. Eight mi-crometer cryosections were collected in the coronal plane and histological analysis was carried out using H&E staining. Cell death was determined by active caspase-3 staining. Results5-weeks following removal of the NP there was significant collapse of the IVD, com-pared to the sham-operated controls. By 7-weeks, fibrocartilage cells derived from the AF were invading the disc space, which became completely filled by 8 weeks. Growth of the disc was reduced in both cranio-caudal and transverse diameters by 30%, compared to control discs. At 2 weeks following removal of NP, there was no cell apoptosis in the AF as determined by active caspase-3 staining. By 8 weeks following the removal of NP, sig-nificant cell apoptosis is seen in the AF. ConclusionRemoval of NP cells leads to invasion of the disc space by fibrous tissue which is very similar to that observed in the human degenerated discs. There appears to be a window of time in which the cells of the AF are alive despite removal of NP cells. A potential exists for intervention during this time to prevent the AF from degeneration.

E-Poster #24

Thoracolumbar Kyphosis Associated to Vertebral Hypoplasia

Pedro Fernandes, Mauricio Daziano, Lori Dolan, Stuart Weinstein

IntroductionThoracolumbar kyphosis with a hooked vertebra has been usually associated with bone dysplasia where the natural history is known to be benign. These anomalies differ from a true posterior hemivertebra as the anterior defect is frequently incomplete. Posterior ele-ments are intact which adds also doing the proper differential with the more serious con-dition of congenital vertebral dislocation.Material and MethodsWe present 8 patients (6 males, 2 females) with “idiopathic infantile” thoracolumbar kyphosis, with a mean follow up of 6 years (22 months -12 years). Mean age at diagnosis was 5 months. Lumbar hypoplasia with a hooked vertebra was present at L1 in five pa-tients and L2 in three. Three patients were premature and inguinal and umbilical hernia repairs were performed in four patients. Patients were ruled out for congenital anomalies and bone dysplasia. All patients were followed without treatment.ResultsMean Cobb angle at detection was 36D (31-51D). No defects were found in posterior vertebral elements. Conus medularis ended between T12 and L2 and no relation was found with level of affected vertebrae. Mean Cobb angle at latest follow up was 9D (0-33D), with complete resolution of kyphosis and vertebral anatomy in four patients and all exhibiting improvement. Resolution was time dependent and no patient had or developed neurological complications.ConclusionInfantile thoracolumbar kyphosis due to vertebral hypoplasia can also affect apparently normal infants. The normal reconstitution of vertebral anatomy with growth and resolu-tion of kyphosis raises the possibility of a combine etiology where mechanical overload may impose vascular compromise to centrum formation. Integrity of posterior elements should make less likely the diagnosis of congenital vertebral dislocation. In theses cases observation is advised despite some possible overall kyphosis progression while infants start to sit and stand as kyphosis tends to resolve spontaneously.

E-Poster #25

Instrumented Convex Hemiepiphysodesis in Treatment of Congenital Scoliosis

Muharrem Yazici, M.D ., H.Gokhan Demirkiran, Houmen Ahmadi, Mehmet Ayvaz,Ahmet Alanay, Emre Acaroglu

Anterior and posterior convex hemiepiphysodesis is a widely used surgical alternative in the treatment of congenital scoliosis. This procedure has the advantage of solving the problem in a single surgery and the disadvantage of the need anterior and posterior surgery. Furthermore, outcome may be unpredictable. Posterior convex hemiepipysodesis with pedicle screws at each segment on the convex side may obviate the need of anterior surgery and make outcomes more predictible.Patients who had posterior convex hemiepiphysodesis with convex pedicle screw instru-mentation for congenital scoliosis between April 2004 and April 2006 were evaluated with preoperative, early postoperative and latest follow-up standing anteroposterior and lateral radiograms.Eleven patients with congenital scoliosis (5 male, 6 female) were inculuded. Average fol-low-up was 18 months (min. 12 months) and average age at the time of operation was 5.6 years. Average curve magnitude was 48.9° (34-60) preoperatively, 40° (28-50) early postoperatively, and 38.1° (22-54) at latest follow-up. There were no wound infections or instrumentation failures during follow-up. In 10 patients curve control or correction was obtained whereas additional surgery was needed in 1 patient with progression due to a misplaced pedicle screw. Our short term results imply that instrumented convex hemiepiphysodesis is a safe and reliable procedure for the stabilization as well as possible correction of congenital scolio-sis.

E-Poster #26

Cell Signaling Pathways in the Growth of Mouse IVD

Chitra Dahia, Eric Mahoney, Atiq Durrani, Christopher Wylie

IntroductionThe aim of the study is to understand the cellular and molecular mechanisms of interver-tebral disc (IVD) growth and development in mouse.Material and MethodsEight micrometer thick coronal and transverse cryosections, from lumbar vertebrae (LV) of one to 48 weeks old male mice were collected. Histology was analyzed by H and E and alkaline phosphatase staining. The number and thickness of the layers of the annulus fibrosus (AF), was measured using DIC optics. Cell proliferation and death was deter-mined by phospho Histone H3 (PH3) and TUNEL staining, respectively. Immunolocal-ization of components of the TGF beta, BMP, FGF and Shh pathways was carried out us-ing confocal microscopy. ResultsDuring the first week, the AF became divided into a fibrous and mineralized component as determined by AP staining. Cells in the mineralized component of AF became hyper-trophic with age. Cell proliferation ceased in the AF and NP after 3 weeks of age. Cells in the NP and fibrous AF secreted Shh which acted on the mineralized AF cells via its patched (ptc) receptor. FGF signaling was ceased at 4 weeks of age at which time BMP and Shh signaling significantly increased. PTHrP expression was observed only in the mineralized AF cells which increased with age. ConclusionAnalysis of active cell signaling pathways suggests that BMP signaling in the NP and fi-brous AF cells stimulates Shh signaling while FGF signaling inhibits this pathway. Shh then acts on the mineralized AF leading to increased expression of PTHrP. These signal-ing pathways seem to be actively involved in disc maintenance.

E-Poster #27

Surgical Treatment for Severe Cervical Kyphosis in Infants with Larsen Syndrome

Félix Tomé-Bermejo , Garrido E. Tucker, SK Thompson, D. Noordeen, HNN

Summary of Background DataLarsen syndrome is known to produce severe cervical kyphosis with life-threatening spinal cord compression. There has been one previous report in the literature treating this condition with insitu posterior fusion with variable success. We show that correction of the deformity is possible using preoperative halocervical traction and final correction with ribstrut grafts and anterior plating. ObjectiveTo evaluate the safety and efficacy of halocervical traction followed by anterior instru-mented fusion with locking plate, for the treatment of severe cervical kyphosis in children with Larsen syndrome.Materials and MethodsThree infants with documented Larsen syndrome and severe cervical hyperkyphosis were treated between 2004 and 2006 in our institution. All three presented with cord compres-sion. Two patients, both 1-year-old of age, were treated with preoperative halocervical traction followed by final correction and stabilisation was with anterior cervical locking plate and rib strut graft. One patient had undergone posterior decompression elsewhere and suffered progressive neurological deficit despite attempted reduction with halocervi-cal traction. ResultsPreoperative kyphosis averaged 130° and was reduced on traction to 70°. Final correction was obtained with anterior strut grafting and plating. Both patients treated operatively made a good neurological recovery. ConclusionsTo our knowledge this is the first report describing the safety and effectiveness of pro-gressive reduction with halo traction followed by anterior strut grafting and internal fixa-tion with anterior locking plate in very young children with Larsen syndrome. Correction of the deformity leads to decompression of the spinal cord and neurological improve-ment.

E-Poster #28

Dual Growing Rod Instrumentation with a Polyaxial Pedicle Screw System in Early-On-set Scoliosis

Dezso J. Jeszenszky, M.D., Friederike Lattig, Frank S. Kleinstuck, Tamas Fulop Fekete, Thomas Forster

IntroductionThere are mainly three different systems used currently for the surgical treatment of se-vere early-onset scoliosis: single rod, dual rod and the vertical expandable titanium pros-thetic rib implant. Good correction and balance of the spine should be achieved as early as possible. Therefore a strong primary fixation is necessary also in the thoracic spine.MethodsThree patients with early-onset double curve scoliosis were treated with a dual growing rod system. There were polyaxial pedicle screws implanted also in the upper thoracic spine in all three patients (T3, T4 in one patient, T4, T5 in two patients). The curves were distracted under continuous spinal cord monitoring to achieve the maximal correction possible. The Cobb angles of the scoliosis were measured pre- and postoperatively. The frequency of lengthening procedures conforms to the curve progression.ResultsAge at surgery was 4.75 (range, 4.3 – 5.6) years. The average preoperative Cobb angle was 57.7° (range, 55-60) in the thoracic curve and 65.7° (range, 60-75) in the lower curve. With the first procedure the thoracic curve improved to 29° (range, 19-45) and the lower curve to 24° (range, 16-39), yielding an over all correction of 57%. The correction improved due to the lengthening procedures to 18.5° of all curves (70%) at the last fol-low-up.There were one screw loosening, one screw breakage. There were no neurological com-plications.ConclusionThe insertion of pedicle screws in the upper thoracic spine is also safe in young children. A dual growing rod system with polyaxial pedicle screw fixation is a strong construct to achieve maximal correction and balance of the spine in severe early-onset scoliosis, al-ready at the initial procedure. The curves will further be corrected with staged lengthen-ing manoeuvres.

E-Poster #29

Progressive Cervical and Cervico-Thoracic Kyphosis in Children

Marco Carbone, Gianluca Piatelli, Gilberto Stella, Armando Cama

The Authors report the cases of 5 children with cervical or cervico-thoracic kyphosis that were treated in their institute.The objective of the study was to evaluate the effectiveness of the treatment in correcting deformities and in improving the neurological deficit.From 2000 to 2007, 5 patients of a mean age of 13 years (6,5-20) were treated. The etiol-ogy of the kyphosis was the outcome of laminectomies for spinal cord tumors (3) and malformative syndromes (2). In 4 cases there was a deformity of the cervico-thoracic junction, in 1 patient a medio-cervical kyphosis. All patients had a neurological involve-ment, with MRI or electrophysiology signs of spinal cord ischemia; all but one mani-fested clinical deficits.In every patient a Halo-vest or a Halo-plaster was applied, depending on the age and on the severity of chest deformity. Surgery was performed through a posterior approach, af-ter a mean period of 3,5 months (1-10) of gradual distraction. A cervical hooks or screws instrumentation was applied and connected to an analogous thoracic device. Multiple dis-cectomies and fusion with use of titanium meshes and bone graft were then performed with an anterior latero-cervical approach. The Halo traction was subsequently removed, and a Minerva brace was worn for several months. Partial neurological recovery was ob-served after surgery. The mean follow-up 1s 3 years (0,5-7); in every case, arthrodesis re-mains complete without loss of correction, the neurological status is stable.The strategy involving Halo traction, posterior instrumentation and fusion, and anterior fusion with titanium meshes seems to be appropriate also in the treatment of pediatric cervical and cervico-thoracic kyphosis. With the latero-cervical approach, the disc be-tween C7 and T1 can be reached without effort. A early diagnosis may lead to a mild re-covery of the neurological deficit.

E-Poster #30

Growing Rods in Neurofibromatosis Scoliosis

Yasser Elmelligy , Hazem Elsebaie, FRCS, M.D., Wael Koptan, M.D., Mootaz Salahel-dine, MSc

Study DesignPreliminary report on children with neurofibromatosis scoliosis treated with growing rod technique. Patients included had neurofibromatosis scoliosis with no previous surgery and a minimum of 6 months follow-up from initial surgery with at least 1 distraction. Ob-jectivesTo determine the safety and effectiveness of the use of growing rod technique in neurofi-bromatosis scoliosis. Summary of Background DataThe growing rod techniques have been used in treating spinal deformities from different pathologies in pediatric age group .Neurofibromatosis scoliosis in pediatric age group has a rapidly progressive course, sharp angles and soft bones where gradual distractions seems suitable. We do not know of any published study exclusively reporting on the re-sults of growing instrumentation in neurofibromatosis scoliosis. MethodsFrom 2005 to 2007, 3 patients (5, 6 and 8 years old) with neurofibromatosis scoliosis un-derwent single growing rod procedures using pediatric Isola instrumentation and tandem connectors. All had curves more than 60° at index surgery 1 had annulotomy as a first stage and they underwent an average of 3 lengthenings ( 1- 5). Analysis included age at initial surgery , number and frequency of lengthenings, increase in T1S1 length and com-plications. ResultsThe mean scoliosis improved from an average of 81° to an average of 40° after initial surgery and was maintained at 40° at the latest follow up . T1-S1 length increased at an average of 1.1 cm per year. During the treatment period, 1 complication occurred a loose set screw leading to loss of correction between lengthening . ConclusionThe growing rod technique seems to be safe and effective in treating neurofibromatosis scoliosis. It can offer the best treatment alternative for these resistant and rapidly progres-sive curves in the very young age group.

E-Poster #31

Can We Predict Cord Anomaly in Congenital Scoliosis?

Hamid Behtash, M.D., Behrooz A.Akbarnia, M.D., Ganjavian, M.S., M.D., E. Ameri, M.D., B. Mobini, M.D., S.H. Tari Vahid, M.D., M. Nojumi, M.D.

BackgroundIn congenital scoliosis, we may see some other anomaly in other part of body so as anomaly of cord, heart, genitourinary system, and . . . .In these patients cord anomaly had important role in outcome and treatment options. In this paper we want to find rela-tive factors that correlate with cord anomaly.MethodIn 381 patients with congenital scoliosis, cord anomaly considered with MRI or myelog-raphy and its relation with patients gender, type and site of vertebral anomaly, curve di-rection, skin lesions and anomaly in other part of body was considered and analyzed.ResultCord anomaly was seen in 83 patients (21.8 % ) that only 26 ones had neurologic abnor-mality in physical examination but had significant correlation (P = 0.000) . Skin lesions (P = 0.001 ) and type 3 vertebral anomaly (P = 0.01 ) had significant correlation with cord anomaly . ConclusionMore than neurologic abnormality in physical examination, in patients with skin lesions or type 3 congenital anomaly, cord anomaly is more common and complete and careful cord evaluation should be done.

E-Poster #32

Instrumentation Without Fusion in Early-Onset Scoliosis

Marco Carbone, Gilberto Stella, Francesca Vittoria, Stelvio Becchetti

The Authors review the cases of 25 children with progressive early-onset scoliosis, who were treated at their institution with growing instrumentation. The objective of the study was to evaluate the effectiveness of this method in controlling deformities and the inci-dence of complications. Surgery was performed with a posterior approach, with bilateral application of two-level hook claws proximally and distally to the curve. The periosteum and laminae were exposed only in these sites, with application of bone graft. Two subfas-cial rods were inserted on each side of the spine and then jointed with one or two domino device and connected to the claws. Two transverse connectors completed the frame. The concavity of the curve was then distracted with spinal cord monitoring. In most cases, a plaster cast was applied for 3 months and then a Milwaukee brace for 12 months. The pa-tients underwent a lengthening procedure every 12 months with a small exposition of the domino connectors and a wake-up test. From 2000 to 2007, 25 children of a mean age of 6.6 years (2-11) were treated with this technique. The etiology of the scoliosis was infan-tile idiopathic (10), malformative syndromes (5), NF (3), congenital (3), others (4). The instrumentation employed were CD Horizon pediatric (11), Isola (6), Legacy (5), others (3). The mean pre-operative Cobb angle was 81° (60-108); the mean post-operative was 43°. A total of 72 lengthening procedures were performed, 5 patients underwent 5 or more lengthenings. The mean follow-up is 45 months (6-86), with a mean Cobb angle of 48°. 4 patients have completed the lengthening period and are scheduled for the final fu-sion, with a good curve control and a fair cosmetic appearence. Complications were com-mon: 5 breakages of the rods, 1 proximal bilateral hooks displacement, 2 crankshaft phe-nomenons, 1 progressive thoracic hyperkyphosis with bending of the rods. The present technique seems to allow a good control of the spinal deformity in young children. A sta-ble correction can be obtained also in the sagittal plane. Mechanical complications are common, but usually easy to resolve. Possible difficulties in performing the final spine fusion will have to be evaluated.

E-Poster #33

Concave Rib Osteotomy (CRO): A Modified Technique Revisited

Youssry El Hawary, M.D ., Ablaa Saleh, Mohamed El Masry

AimTo report on the efficacy of CRO in conjunction with posterior instrumented fusion in the treatment of adolescent idiopathic scoliosis (AIS). Summary of BackgroundThe accepted treatment for large rigid curves is a combined anterior release with poste-rior fusion which has been demonstrated to have 10.2 percent. pulmonary complications. The concept of (CRO) was introduced by Flinchum in 1963. Cadaveric studies tested flexibility before and after sectioning the ribs on the concave side, and found an average increase in deflection of 53 percent. However there are little published data reporting the efficacy of such technique. MethodsA prospective cohort of 78 patients diagnosed as having AIS with a Cobb angle greater than 70°. All patients underwent posterior instrumented spinal fusion, iliac crest bone grafting and CRO. Our modifications of the technique included using a gauze swab un-derneath the osteotomised ribs to protect the underlying pleura, and creating a sling to lift the lateral ends of the ribs above the concave rod. We also filled the area with saline to-gether with the use of positive ventilation to check for air leaks. No chest tubes were in-serted routinely.Pulmonary rehabilitation program (PRP) commenced one week postoperatively. ResultsThe overall incidence of pulmonary complications was 11.5 percent (9 patients). Two pa-tients had air leaks from the pleural cavity intra-operatively. Post-operatively, four pa-tients developed pneumothorax; and three had a pleural effusion. There were no post op-erative wound complications and no neurological complications. There was a mean of 68 percent curve correction. At 2 years follow up, there was no evidence of pseudoarthrosis, but there was a mean loss of correction of 3° (range 2-4). ConclusionsThe addition of CRO to posterior instrumented fusion in patients with AIS is a safe and reliable method in the treatment of severe and rigid curves.

E-Poster #34

Role of P factor in AIS Initiation and Curve Progression

Alain Moreau, M.D., Bouziane Azeddine, M.Sc., Anita Franco, M.Sc., Isabelle Turgeon, B.Sc., Mamadou Samba Boiro, B.Sc., Sacha Blain, B.Sc., Hugo Boulanger, B.Sc., Keith M. Bagnall, Ph.D., Benoit Poitras, M.D., Hubert Labelle, M.D., Charles-Hilaire Rivard, M.D., Guy Grimard, M.D., Jean Ouellet

IntroductionAdolescent idiopathic scoliosis (AIS) is the most common form of scoliosis and we hy-pothesized that scoliosis development in AIS patients and different melatonin-deficient animal models could be induced by a similar mechanism involving a common down-stream effector regulated by melatonin. In that context, we have identified a specific mol-ecule, that we named the P factor and tested the hypothesis that elevated plasma P factor relates to AIS initiation and curve progression. MethodsWe studied 109 patients with AIS divided into two subgroups according to the severity of their spinal curve (Cobb’s angle ≤ 45° vs. ≥ 45°) and 37 healthy control subjects. Plasma concentrations of P factor and soluble P factor receptor (sFPR) were measured by en-zyme-linked immunosorbent assays. Unilateral (one-tail), unpaired Student’s T-tests with equal variance were performed to compare the difference in plasma levels between AIS and control groups. We also studied genetically modified bipedal C57Bl6/j mice devoid of either P factor or its receptor to assess the mechanism whereby this secreted factor triggers scoliosis.ResultsPlasma concentrations of P factor were significantly higher in patients with AIS having a Cobb’s angle ≥ 45° than AIS patients with a Cobb’s angle ≤ 45° or in controls (1028.34 ng/mL, 733.18 ng/mL and 561.39 ng/mL respectively). Conversely, plasma sFPR con-centrations were significantly decreased in both AIS patients groups when compared to controls (535.44 ng/mL, 547.64 ng/mL and 864.13 ng/mL respectively). Bipedal C57Bl6j mice developed a scoliosis in a proportion of 45% while none of the genetically modified bipedal mice developed a scoliosis. ConclusionsElevated plasma P factor and low sFPR levels were found to be associated with scoliosis initiation and curve progression. Study of genetically modified C57Bl6/j mice further confirmed that scoliosis induction by P factor was mediated through interactions with its receptor while sFPR can act as a disease modifying factor by interfering with P factor signaling. Moreover, these biochemical tests can be performed without any prior knowl-edge of mutations in any defective genes causing AIS.

E-Poster #35

The Meaning of the Autonomic Nerve System in Etiology of AIS

Martin Repko , Drahomir Horky, Martin Krbec, Richard Chaloupka, Irena Lauschova

IntroductionThe main purpose of this study is to search the possible causation of idiopathic scoliosis in development changes of the autonomic nerve system (ANS). In our prospective study we followed the changes of autonomic nerve structures, as well as discrepances between concavity and convexity of the scoliotic curve. Material and MethodsWe evaluated 9 patients treated for idiopathic scoliotic deformities and control set of 3 patients without scoliotic deformity within the period March-November 2005. We took the samples of peripherial autonomic nerves from convexity and concavity of the scoli-otic deformity during the surgical correction using the transthoracic approach. We exam-ined the samples using the electronmicroscopic method. Then we applied the morphomet-ric statistical evaluation for comparison with control samples which have been taken dur-ing the surgical treatment of non-scoliotic patients. ResultsThere were 23,71% of myelinised nerve fibres (MNF), 12,21% of unmyelinised nerve fi-bres (UNF) and 5,0% of Schwanns cells (SC) in samples from scoliotic convexity mea-sured by morphometric method. There were 17,36% of MNF, 5,82% of UNF and 5,27% of SC in samples from scoliotic concavity . In control non-scoliotic samples there were 29,9% of MNF, 19,9% of UNF and 16,7% of SC.Discussion and ConclusionTrunk and rib cage developmental asymmetry seems like one of possible etiology of idio-pathic scoliosis. These deformities can be induce by asymmetrical intercostal vascular nutrition due to changes in ANS. There were the main morphological abnormalities of ANS in scoliotic concavity expressed in the electronmicroscopic evaluation as degener-ated nerve fibers, massive lesion and separation of the myelin sheath, vacualization of the Schwanns cells cytoplasma and condensation of the cytoblast. All these changes had been not found in control set of patients without scoliotic deformities.This findings can help us in the search for the scoliotic etiology.

E-Poster #36

The Changes of Scoliotic Sagittal Profile

Martin Repko , Martin Krbec, Richard Chaloupka, Milan Leznar, Vladimir Tichy, Tomas Obtulovic

AimSurgical correction of the frontal as well as sagital planes impact the standing and sitting stability. The aim of our prospective study is the measurement of the changes in sagittal plane in correlation with types of segmental instrumentation for posterior approach. Material and MethodsWe evaluated 96 scoliotic patients surgically managed by posterior correction and stabili-sation by various segmental instrumentations (USS, SSE, ISOLA, Miami, TSRH). There were 76 idiopathic and 20 neuromuscular scoliotic deformities. We evaluated x-ray pa-rameters on sagittal films. We assessed kyphosis and lordosis in degrees according to Cobb. Sagital tilt a T9 tilt has been assessing according the degrees according to Duval-Beaupere. Results. There were mean preoperative values of the thoracic kyphosis +24,0° (+/-18,3) and postop +24,3 (+/-15,6) in idiopathic scoliotic group. Lumbar lordosis were preop -52,7 (+/-23,1) and postop -54,9 (+/-15,5). In group of neuromuscular scoliosis there were correction of thoracic kyphosis from preop values +42 (+/-18) to postop +36 (+/-10). Lumbar lordosis has been corrected from preop value -60 (+/-14) to postop -49 (+/-12). In group of idiopathic scoliosis there were reduction of the T9 tilt from preop +7,7 (+/-9,7) to postop +7,1 (+/-4,3), and sagittal tilt from preop +2,7 (+/-4,4) to postop +2,1 (+/-4,4). In group od neuromuscular scoliosis there we reduction of the T9 tilt from +6,8 (+/-4,9) to postop +3,1 (+/-5,9), and sagittal tilt from preop +3,1 (+/-5,9) to postop +1,6 (+/-2,5). Conclusion. Surgical technique of the segmental instrumentation in scoliotic deformities allows good correction not only in the frontal plane, but also in sagittal plane. There were statistically significant changes in the group of neuromuscular scoliosis. There were not the significant statistical changes in types of segmental instrumentations.

E-Poster #37

Neck Muscle Asymmetry in a Case of Idiopathic Scoliosis

Asghar Rezasoltani , Heikki Kauhanen, Ph.D., Veikko Avikainen, M.D.

Background and PurposeDifferent methods have been used in the evaluation of the patient with idiopathic scolio-sis. Ultrasonogeraphy is a non-invasive technique in the study of muscle function. The purpose of this study was to evaluate the neck semispinalis capitis muscle (SECM) size in a patient with idiopathic scoliosis. Case DescriptionThe subject was a fifteen-year old high school female student. The Cobb angles were 43° for the thoracic curve and 25° for the lumbar curve. OutcomesThe clinical diagnosis was idiopathic scoliosis with primary right thoracic and compen-satory left lumbar curves with no curvature in the cervical region. The cross-sectional area (CSA) and linear dimensions of the SECM were measured by real-time ultrasonog-raphy. The CSA was 25.3 % smaller on the right side than on the left side. The muscle was rounder on the left side than on right side. The difference between the sides was out-side the normal range as determined in our earlier study in healthy females (0-16 %). DiscussionUltrasonography appeared be a useful method for screening muscle asymmetry in a pa-tient with idiopathic scoliosis.

References 1. Rezasoltani A, Kallinen M, Malkia E, Vihko V. Neck semispinalis capitis muscle size in sitting and prone position measured by real-time ultrasonography. J Clin Rehabil. 1998; 12: 36-44

Cases

Case #1

Posterior Hemivertebra Resection without Fusion in a Two Year Old Child

Dezso J. Jeszenszky, M.D., Tamas Fulop Fekete, Friederike Lattig, Frank S. Kleinstuck

IntroductionResection of a hemivertebra from a posterior approach is a widely accepted technique. This technique requires a short segment fusion. Aiming for motion preservation at the mobile lumbar area by avoiding fusion is worth considering. We present a case and de-scribe a fusionless surgical technique. A surgical method to correct spinal deformity by fusionless hemivertebra resection in congenital scoliosis has not been reported before.Surgical Technique24 months old girl with a semi-incarcerated hemivertebra between the L2 and L3 on the right side, resulting in progressive scoliosis, was operated. Preoperative radiographs and CT scans showed that reconstruction of a facet joint between the right articular processes of the L2 and L3 vertebras is technically feasible. The surgical technique consisted of placing transpedicular screws in the right pedicles of L2 and L3, removal of the hemiver-tebra, taking care to preserve the joint capsules and the cranial endplate of the hemiverte-bra. After resection, a posterior tension band was applied by connecting the screw heads with wire. The joint capsules were connected by sutures. A brace was applied postopera-tively for 3 months, the implants were removed subsequently.ResultsPreoperative the right convex lumbar scoliotic curve was 41° between L1 and L4, sagittal kyphotic deformity was 12° between L2 and L3 with subluxation. 14 years later, the scol-iotic curve was 5° between L1 and L4. The kyphotic deformity has been corrected, the lordosis was 12° between L2 and L3 at followup.ConclusionCorrection surgery of congenital scoliosis should be performed early, before the develop-ment of severe local deformities and secondary structural changes. This allows normal growth in the unaffected parts of the spine. Posterior resection of the hemivertebra with transpedicular instrumentation allows for excellent correction in the frontal and sagittal planes.When performing surgery for hemivertebra resection, careful anatomical analysis is rec-ommended to asses the applicability of above described technique, to preserve motion in the affected segment.

Case #2

Infantile Idiopathic Scoliosis

Toru Maruyama , Katsushi Takeshita

At the first presentation, when the patient was 1 year old, he had right thoracic curve from T5 to T11 with Cobb angle of 21° in the lying position. His curve gradually pro-gressed to 53° when he was referred to our clinic at the age of 5y 1m. Despite bracing, his right thoracic curve from T5 to T11 and left lumbar curve from T11 to L4 progressed to 81/55° at the age of 10y 8m. His 81° thoracic curve was corrected to 61° on the supine bending radiograph and 55° lumbar curve was corrected to 24°. At the age of 11y 3m he underwent definitive fusion surgery, anterior release from T8/9 to T10/11 using video as-sisted thoracoscopy and posterior instrumentation from T4 to L1 using hooks, sublamina cables, and pedicle screws. His curve was corrected to 25/20° and the correction was maintained 6 months after surgery. How would be the results changed if we could use the growing rod system?

Case #3

Congenital Myopathy

Toru Maruyama

Scoliosis with congenital myopathy, type 1 fiber predominance.On newborn, the patient had asphyxia, dyspnea, dyaphagia, and eye and facial palsy. For the first 2 months she had been respirator dependence. At the age of 2, she began ambula-tion and oral intake. A magnitude of her left thoracolumbar curve from T8-L3 was 25° at the age of 1y 5m in the supine position, but deteriorated to 70° at 2y 6m in the sitting po-sition. Despite bracing, her curve gradually progressed to 112°, which was corrected to 44° on the supine side-bending radiograph. At the age of 9y 9m she underwent definitive fusion surgery, posterior instrumentation from T5 to L3 using hooks, sublamina cables and pedicle screws. Her curve was corrected from 112° to 30° by the surgery and the cor-rection was maintained as Cobb angle of 31° 1 year after surgery. How would be the re-sults changed if we could use the growing rod system?

Case #4

Juvenile Idiopathic Scoliosis

Toru Maruyama , Katsushi Takeshita, Tomoaki Kitagawa

At the first presentation, when the patient was 4 year and 11 month old, she had right tho-racic curve from T5 to L1 with Cobb angle of 44°. Despite bracing, her curve from T5 to T11 progressed to 77° at the age of 9y 2m. At the age of 10y1m her 87° thoracic curve was corrected to 79° on the supine bending radiograph. At the age of 10y 6m she under-went definitive fusion surgery, anterior release from T5/6 to T10/11 using video assisted thoracoscopy and posterior instrumentation from T2 to L2 using hooks, sublamina wires and pedicle screws. Her curve was corrected from 113° to 52° by the surgery and the cor-rection was maintained as Cobb angle of 51° five years after surgery. How would have been the results changed if we could use the growing rod system?

Case #5

Congenital Scoliosis Case Report

Sumon Bhattacharjee , M.D.

HF is 7 year-old female with a known congenital hemivertebrae with associated other anomalous vertebral body formation. The patient at the age six (6+0 years) underwent a convex growth arrest procedure with posterior convex arthodesis without instrumenta-tion. The patient continued to experience progression of her thoracolumbar curve from 32 to 56° over a six-month period. There was overall loss of truncal balance with an associ-ated kyphotic deformity of 50° across the thoracolumbar junction. The patient was also noted to have some gait difficulties, with MRI demonstrating the presence of a syrinx at the level of the conus medullaris. The patient on the bending x-rays showed an overall flexible curve but significant rigidity across the apex of the deformity, which was associ-ated with the hemivertebrae. The patient at age 7+1 years underwent a posterior only ap-proach for correction of her deformity. Multilevel Smith –Petersen osteotomies were performed across the posterior fusion mass. Posterior based hemivertebrae resection was achieved and pedicle screw instrumented fusion was performed across the segments from T11to L3. The postoperative follow-up x-rays, coronal curve was measured at 18°, with 10° thoracolumbar kyphosis on the sagittal plane. Restoration of spinal balance was achieved and improvement in gait and mobility was noticed. There were no adverse peri-operative complications. This case report demonstrates that when convex growth arrest fails in congenital deformities, aggressive posterior only correction methods with pedicle screws instrumented fusion in young children can safely achieve spinal balance.

Case #6

L4-5 High Grade Spondolysthesis in a Skeletally Immature Patient

Sumon Bhattacharjee, M.D.

High grade spondolysthesis in the pediatric skeletally immature patient and its surgical correction is often reported involving the L5-S1 segments. No particular surgical correc-tion strategy for high-grade L4-5 spondolysthesis could be identified in the literature after an extensive Medline search.SR was 11+11 year old pre-menarche female, presented with hamstring tightness and a depression in the lumbar region that was noted by her mother. The patient was Risser 0, and x-ray revealed the presence of Grade IV spondolysthesis. The patient on the coronal plane was noted to have a reactive scoliosis, with a thoracolumbar deformity measuring at 15°. Brief management with TLSO brace and leg extension was tried, with no signifi-cant success. MRI scan, demonstrated prominent herniated disc with doming of the L5 superior endplate. The sagittal x-rays demonstrated a prominent slip angle of 62° at the level of the spondolysthesis.A novel correction technique, with an entirely posterior based approach for the deformity correction was applied. Pedicle screws were placed from L3 though S1. Long post reduc-tion screws were placed at L4, and short post at the other levels. Interbody fusion with PEEK interbody cage was performed at the L5-S1 level. Wide decompression with ex-tended exposure of the both the L4 and L5 nerve was achieved bilaterally. A through dis-ckectomy with bilateral approach was performed, and complete exposure and preparation of the bony endplates. Osteotomy of the L5 dome endplate was performed. Using the L5-S1 as the base of the construct, the L4 segment was reduced on the superior endplate of L5, with close neurophysiological monitoring. Bone-on bone fusion was achieved be-tween L4-L5, with significant correction of slip angle. Postoperative follow-up shows posterolateral and interbody fusion and maintenance of slip angle correction without any neurological sequale. There was resolution of the reactive thoracolumbar scoliosis.

Case #7

Lumbar Agenesis: From Intrauterine Diagnosis to Spinal Reconstruction

Marco Teli, M.D., Giuseppe Grava, M.D., Alessio Lovi, M.D., Marco Brayda-Bruno, M.D.

Study DesignFollow-up of a case of lumbar agenesis treated with spinal reconstruction, with review of the pertinent literature. BackgroundCongenital absence of isolated segments of the lumbar spine is rarely described. Differ-ential diagnosis includes congenital dislocation of the spine, lumbo-sacral agenesis, spinal dysgenesis and spina bifida.MethodsThe absence of spinal segments was suspected on an ultrasound scan and confirmed by X-rays at birth of a female showing thoracolumbar kyphosis and meningocele with bilat-eral talipes and paraplegia. X-rays confirmed absence of T12, L1, L2 and partially L3, with presence of spina bifida of the caudal segments. The spine was protected by serial casting and bracing until the eight year of life, when progression of kyphosis mandated spinal reconstruction. This was performed through a postero-lateral approach.ResultsDeformity improved to normal kyphosis after posterior spinal fusion. The girl 36 months after surgery is enjoying pain-free activities, attending school and playing in sitting posi-tion.ConclusionLumbar agenesis has sporadic incidence. No etiologic factor is known. Its functional prognosis is dependent on the level of neurologic impairment. Survivorship into adoles-cence has been described. We showed the disease may be suspected by uterine ultrasound before birth, and spinal reconstruction can be undertaken in the occurrence of progressive deformity, with promising results.

Case #8

A Rare Case of Spinal Pediatric Osteoblastoma

Gianluca Piatelli, Marco Carbone, Carlo Gandolfo, Andrea Rossi, Paolo Nozza, Miriam Tumolo, Armando Cama

PurposeThe aim of this study is to report a pediatric case of osteoblastoma associated with an aneurysmal bone cyst (ABC) involving the lumbar spine.Materials and MethodsA 2 year-old male with back pain, right lower limb tremor and progressive inability to walk underwent clinical, MRI and CT examinations. They showed a pathological L2 ver-tebral body with a large amount of extra and intraspinal soft tissue containing large flow voids, with a compression of the conus apex and of nerve roots. Owing to a progressive neurological deficit, the child was operated on emergency. Profuse bleeding occurred during surgery: only a partial spinal decompression and histological diagnosis was possi-ble. The patient then underwent catheter angiography, showing a highly vascularized mass that was selectively embolized with cyanoacrylate glue trough lumbar arteries in or-der to decrease the degree of vascular feeding and intra-operative hemorrhage risk. Then a first posterior surgical approach was performed with decompressive laminectomy and posterior arthrodesis instrumented with hooks from T11-T12 to L2-L3. A second anterior approach was performed with right hemicorpectomy and arthrodesis with a cage between L1-L3.ResultsComplete neurological recovery after surgery was obtained.ConclusionOsteoblastoma is a rare primary bone neoplasm derived from well-vascularized stroma of connective tissue. Osteoblastoma may affect any bone; in the spine, it involves most fre-quently the posterior arches. The diagnosis is based on a combination of plain radiogra-phy, CT, MRI, and angiographic studies, but can be very difficult. A biopsy is often nec-essary for a histological diagnosis. While osteoblastoma can be histologically undistin-guishable from osteoid osteoma, both clinical/neuroradiological features and biological behavior can be significantly different. As many as 10% of patients with osteoblastoma have associated ABC components that may potentially bleed, either spontaneously or during surgery. Pre-operative selective embolization is useful to reduce bleeding risk dur-ing surgery. The goal of the treatment is the complete removal of the lesion and spinal stabilization is often required.

Case #9

A case of Rapidly Progressive Infantile Scoliosis

Kazuhiro Sato , Ken Yamazaki, Hirooki Endo, Satoshi Yoshida, Hideki Murakami, Tadashi Shimamura

CaseTwo year old infant, malePast Medical HistoryThe patient had not been treated although scoliosis was noticed by his mother since his birth.He was diagnosed with scoliosis at the age of 1 year and was referred to our hospi-tal. Upon the first visit, a left convex thoraco-lumber curve (Apex Th11) was observed. The Cobb angle was 32°. No congenital abnormality was seen in his spinal column. The patient remained under observation as an outpatient, but the angle aggravated to 54° at the age of 1 year and 9 months. At that time, treatment by an under arm brace was initi-ated. At the age of 2 year and 1 month, his condition rapidly aggravated to a Cobb angle of 75°, and was admitted for a surgical operation. Physical FindingsHeight 82.5 cm, Body weight 11.5 kg.Operation MethodMinimal exposure was given. A pedicle screw (3.5mm in diameter, 20mm in length) was to be inserted in the vertebrae at L3 and L4. However, the pedicle diameters at Th3 and Th4 were found to be 2.2mm and 1.7mm, respectively, according to pre-op CT. No screws compatible with these sizes were available. Therefore, pedicle screws(3.5mm in diameter, 20mm in length)were inserted by the in-out-in method under the fluoroscopic observation of the pedicles, and facet fusions at Th3/4 and L2/3 were performed. Exten-sion of the correction was made with a wedding band using a Titanium 4.75 mm dual-rod. The Cobb angle improved to 21° post-operatively.DiscussionRapidly progressive infantile scoliosis must be treated at an early stage. However, no ef-fective treatment method has been established yet. In a rapidly progressive case, the preparation of strong anchors for in-out-in method at an early stage seems to be indicated. In this case, 3.5mm cervical pedicle screws were inserted by the in-out-in method and used as anchors. Considering the current situation in which there is no suitable type or size of pedicle screw system available, the decision to shorten the time required in order to prepare a strong anchor by fixation seemed appropriate in this rapidly progressive case. ConclusionThe pedicle screw system is a good method to shorten the time required to prepare a strong anchor in a rapidly progressive case.

Case #10

Navigation Surgery in Juvenile Congenital Scoliosis

Katsushi Takashita , Toru Maruyama, Atsushi Seichi, Kozo Nakamura

Relatively small sizes of the spine have been hindering full adaptation of the pedicle screw system in infantile/juvenile scoliosis surgery. Individual unique shapes are also major concern in congenital cases. Though several surgeons reported the beneficial use of navigation system in scoliosis surgery, its effectiveness in infantile scoliosis might be ob-scured because of its tiny structure as well as a relatively large component of cartilage which is not usually incorporated in constructing the virtual spine. We report of the suc-cessful utilization of navigation technique in placing pedicle screws in small and de-formed congenital scoliosis. Eight-year-old presented with back deformity with congeni-tal scoliosis. The Cobb angle was 46° from T5 to T12. Computed tomography revealed right unilateral unsegmented bar at T6 to T9, left hemilamina at T10 and right fused lami-nae at T7 to T9. Posterior-only in situ fusion was planned. Preoperative CT data was in-put into the navigation software, and the placement level, direction and depth of screws of each pedicle screw placement were determined in accordance of individual spine shape. Segmental pedicle screw instrumentation with ten screws was performed with no sequelae. With three-year follow-up, there is no instrument failure, no Crankshaft phe-nomenon, and no progress of the decompensation curve. Navigation system is useful in placement of pedicles screws as well as in individualized preoperative planning.

Case #11

Use of VEPTR in Severe Infantile Scoliosis Below Age 6

Pierre Lascombes, T Haumont, P Journeau

The treatment of severe infantile scoliosis remains a challenge. When bracing is unable to stop the progression of the curve, a surgical procedure can be considered. Subcutaneous rods have some disadvantages including early ossification and the inherent difficulty of the final surgical arthrodesis. Rib distraction is an alternative which could be more effi-cient, as the corrective strength is lateral to the spine.Material and Method One girl, aged 6 years developed an upper thoracic 90° curve after a complex congenital diaphragmatic hernia. Two concave VEPTR were inserted, one from rib 3 to 9 and one between the rib 4 and L1.One boy, three years old, had an idiopathic thoracic scoliosis of 90°. One distractor was fixed on the left concave side between rib 3 and L3; the second distractor was placed on the right convex side from rib 3 to the iliac crest. Lengthening was performed once per year. ResultsOne major difficulty resides in the size of the implants, including the vertebral implants, in this age group. In case 1, it was impossible to insert a secure double laminar hooks on L1. The case 2 was programmed to have a bilateral fixation from the iliac crest, but it would have been totally impossible to close the surgical wound, as the iliac hook was too big. In both cases, the proximal rib fixation dislodged when the distal part was anchored on a lumbar vertebrae or the iliac crest, necessitating a change of proximal anchorage. A new rib was spontaneously remodelling below the hook. However, the CTscan showed clearly the inappropriate diameter of the rib hook compared to the rib size, which proba-bly led to a poor anchorage.DiscussionAdaptation of implant size must be considered for younger children, including the rib hooks, the vertebral and iliac implants.