FDA DEVICE/DRUG STATUS: This abstract does not discuss or include

any applicable devices or drugs.

doi: 10.1016/j.spinee.2009.08.344

P86. Combined Plasma-Mediated Radiofrequency Ablation and

Cement Augmentation for Spine Tumors Diagnosed as Multiple

Myeloma, Lymphoma, and Plasmacytoma

Bassem Georgy, MD; University of California, San Diego, San Diego, CA,

USA

BACKGROUND CONTEXT: Vertebral body compression fractures

(VCFs) secondary to advanced lesions of multiple myeloma (MM), lym-

phoma, or plasmacytoma of the spine can be complicated by cortical de-

struction and/or epidural extension, which are considered relative

contraindications to conventional percutaneous vertebroplasty and percuta-

neous vertebral augmentation (balloon kyphoplasty). Typical recourses are

either management with pain medication, or extensive surgery which car-

ries a high mortality and morbidity in this patient population. A new pro-

cedure, plasma-mediated radiofrequency ablation combined with bone

cement augmentation, allows for minimally-invasive treatment of spine le-

sions in these traditionally challenging patients.

PURPOSE: To evaluate whether the placement of bone cement in the an-

terior two-thirds of the vertebral body to stabilize the spine could be

achieved using this new treatment, enabling stabilization in a patient set

which is difficult to treat by conventional means. The radiographic evi-

dence of bone cement deposition patterns and extravasation in the treated

vertebral bodies was studied post-procedure. Pain relief was also measured

pre- and post-procedure.

STUDY DESIGN/SETTING: Prospective case series of patients with

VCFs secondary to spine lesions of MM, plasmacytoma, or lymphoma.

PATIENT SAMPLE: The 12 patients prospectively included in our study

had painful VCFs secondary to advanced lesions of MM (n56), plasmacy-

toma (n54), or lymphoma (n52) in the vertebral body (16 levels). All

cases were accompanied by cortical destruction and/or epidural extension.

OUTCOME MEASURES: Computed Tomography (CT) imaging was

performed immediately before and after the procedure. Pain alleviation

was measured using visual analogue scale (VAS) scores both pre-opera-

tively and at follow-up 2-4 weeks post-procedure.

METHODS: A void was created in the anterior portion of the tumor-infil-

trated vertebral body by using a bipolar plasma radiofrequency-based

wand (ArthroCare Corporation, Austin, TX) to ablate channels in the ma-

lignant mass. Bone cement (Zimmer, Warsaw, IN) was injected into the ab-

lated cavity under fluoroscopic guidance. Pre- and post-operative CT scans

were performed to evaluate cement deposition in relation to the metastatic

lesion and cement extravasation. Pain relief was evaluated using VAS both

pre- and post-operatively.

RESULTS: 75% of the cement was deposited in the anterior 2/3 of the ver-

tebral body in all but 2 levels. Minimal clinically insignificant extravasa-

tion was noted in 11 levels (venous: 8, cortical: 2, discal and epidural:

1). VAS pain scores were available for 9 patients; 5 (plasmacytoma: 3,

MM: 2) showed significant improvement (VAS reduction $ 4), 2 (both

lymphoma) showed moderate improvement (VAS reduction $ 2), and 2

(both MM) showed no change.

CONCLUSIONS: Combining two minimally-invasive procedures, plasma-

mediated radiofrequency ablation and bone cement augmentation, enables

treatment of advanced metastatic spine lesions in MM, plasmacytoma, and

lymphoma patients, including thosewith epidural extension and/or cortical de-

struction. Most of these patients are not candidates for open surgery, and so this

less-invasive technique allows pain relief by stabilizing the anterior part of the

vertebral body with a predictable and safe cement deposition pattern. This pain

relief allows patients to better comply with their oncologic treatments. Cement

extravasation appears clinically insignificant when using this technique.

FDA DEVICE/DRUG STATUS: Cavity Spine Wand: Approved for this

indication.

doi: 10.1016/j.spinee.2009.08.345

P87. Neurophysiological Changes in Deformity Correction of

Adolescent Idiopathic Scoliosis with Intra-Operative Skull-Femoral

Traction

Randolph Gray, MBBS, FRACS1, Laura Holmes, BSCH, CNIM2,

Samuel Strantzas, MSC, DABNM2, Christian Zaarour2, Stephen Lewis,

FRCS(C), MD, MSC2; 1Krembil Neuroscience Centre, Toronto Western

Hospital, Toronto, Ontario, Canada; 2Hospital for Sick Children, Toronto,

Ontario, Canada

BACKGROUND CONTEXT: Intra-operative skeletal traction is used to fa-

cilitate coronal plane deformity correction. Its use can be associated with spinal

cord stretching and ischemia with resultant electrophysiological changes. The

prevalence of such changes, its clinical significance and safety is unknown.

PURPOSE: To determine the prevalence and significance of neurophysi-

ological changes with intra- Operative skull-femoral traction in facilitating

correction in scoliosis surgery. We also set Out to ascertain the predictive

risk factors associated with these changes and methods of Minimizing the

risk of spinal cord injury with acute intra-operative skeletal traction.

STUDY DESIGN/SETTING: Retrospective review of prospectively col-

lected data of 38 consecutive coronal plane deformity corrections in Idio-

pathic scoliosis patients.

PATIENT SAMPLE: After exclusion of two patients with non-traction re-

lated changes, 37 consecutive procedures in 36 patients with a mean age of

15.4 (11.4-17.9) years were reviewed.

OUTCOME MEASURES: Motor Evoked Potentials (MEP), Somatosen-

sory Evoked Potentials (SEP) and postoperative clinical neurological status

were used as primary outcome measures. Curve Flexibility index, Traction

index, location of the major curve and pre-operative Cobb angle of the ma-

jor curve were used as predictive factors.

METHODS: Radiographs and charts were reviewed of 38 consecutive

scoliosis patients treated with intra-operative skull-femoral traction be-

tween 2005 and 2008. All patients had SEP and MEP monitoring.

RESULTS: The mean skull traction was 8.6kg (6.8-11.3) and femoral trac-

tion was 22.3 kg (13.6-31.7). Intra-operative MEP changes occurred in 18/

37(48%) and SEP changes in 1(2.7%) procedure. The 18 cases with MEP

changes had a mean Cobb of 86�, curve flexibility index of 0.14, and 41%

correction with traction compared to 70�, 0.27, and 50% in the 19 cases with-

out MEP changes (p!0.05). Intra-operative interventions were performed in

response to the changes in MEP resulting in complete bilateral recovery in

10/18 (55%), complete unilateral recovery with partial contralateral recov-

ery in 6 (33%) and incomplete bilateral recovery in 2 (11%) patients. There

were no patients with unrecordable MEP or SSEP amplitudes at wound clo-

sure. There were no post-operative neurological deficit.

CONCLUSIONS: Intra-operative traction is associated with frequent ab-

normalities in MEP monitoring. The thoracic location of the major curve,

mean Cobb angle of 86�, and increased rigidity (low traction and flexibility

index) are risk factors for changes in MEP monitoring with traction. Most

of the neurophysiological changes reversed completely with one or more

of the maneuvers of reduction of traction, complete removal of traction,

and rod loosening whilst optimizing cord perfusion and oxygenation.

Others recovered incompletely with the same approach The presence of

any MEP recordings at closure independent of its amplitude was associated

with normal neurological function. Intra-operative traction should not be

used in the absence of MEP monitoring. SSEP as the sole means of mon-

itoring is strongly discouraged.

FDA DEVICE/DRUG STATUS: This abstract does not discuss or include

any applicable devices or drugs.

doi: 10.1016/j.spinee.2009.08.346

P88. Minimally Invasive Instrumentation and Fusion of

Thoracolumbar Spine Fractures

Bob Greenleaf, MD1, Daniel Altman, MD1, J. Brad Bellotte, MD2,

Bradley Palmer, MD2, Lauren O’Keefe2; 1Pittsburgh, PA, USA; 2Allegheny

General Hospital, Pittsburgh, PA, USA

BACKGROUND CONTEXT: Minimally invasive, percutaneous tech-

niques are available to insert pedicle screw and rod constructs for

159SProceedings of the NASS 24th Annual Meeting / The Spine Journal 9 (2009) 1S-205S