femoral deformity and deficiency in complex primary & revision tha david a. mattingly, md chief,...
TRANSCRIPT
Femoral Deformity and Deficiency in Complex Primary & Revision THA
David A. Mattingly, MD
Chief, Joint Reconstruction
Director, Otto E. Aufranc Fellowship
New England Baptist Hospital
Boston, MA
Femoral Deformity
• Developmental Dysplasia (DDH)
• Prior Surgery ( THR, Osteotomy )
• Post-traumatic
• Secondary Osteoarthritis– LCP; SCFE; Sepsis
• Coxa Vara & Coxa Valga
Femoral Deformity
• Small Femoral Canal– JRA; Dwarf; SED
• Large Femoral Canal– RA, AS, ETOH
• Paget’s Disease
Preoperative Planning
• Complete H&P– Leg lengths;N/V status
• X-Ray Evaluation
– AP Pelvis& Hip (Marker)
– Lauenstein lateral– CT; scanogram
*Identify equipment, prosthetic, osteotomy and bone graft requirements.
Femoral Deformity in THA
THA In Femoral Deformity
• Individualize Management
– Level of deformity
– Type of deformity
– Bone quality
– Patient factors
– Surgeon preferences
THA In Femoral Deformity
• Location of Deformity– Greater Trochanter– Femoral Neck– Metaphysis– Metaphyseal-Diaphyseal– Diaphysis– Distal to Diaphysis
Surgeon Requirements
• Proper Implant Selection
• Exact Implant Positioning
• Select Proper Surgical Approach
• Specialized Techniques– Trochanteric osteotomy– Corrective osteotomy– Leg lengthening
Treatment Options
1. Alter bone to fit prosthesis (osteotomy)
2. Select prosthesis to fit femur
3. Short implants or surface replacement to avoid more distal deformity
THA In Femoral Deformity
Greater Trochanteric Solutions
• Trochanteric Osteotomy (exposure)
• Trochanteric Advancement
THA In Femoral Deformity
Femoral Neck
• Varus
• Valgus
• Abnormal Version
THA In Femoral Deformity
Abnormal Version
• Cement small femoral implant in proper anteversion independent of anatomy
• Modular cementless implants
• Derotational osteotomy (subtrochanteric)
Implantation
Modular Advantages
• Goal: Avoid hard bearing impingement while maximizing range of motion.
• The ability to adjust femoral anteversion after cup placement has become increasingly important when using hard bearing implants where only neutral acetabular liners are available.
• The ability to adjust femoral anteversion after cup placement has become increasingly important when using hard bearing implants where only neutral acetabular liners are available.
THA In Femoral Deformity
Metaphyseal
• Cemented implants
• Uncemented modular
• Uncemented distal fixation
• Resect deformity, replace with implant
THA In Femoral DeformityMetaphyseal
CAUTION!!!!– Osteotomy
• Small fragment
• Fixation difficult
– Monoblock Metaphyseal Filling Implants• Fracture
• Poor fit
THA In Femoral DeformityMetaphyseal - Diaphyseal
• Mismatch
• Large canals
• Small canals
• Deformity
Enlarged Femoral Canal
Cement Cementless modularExtensively coated (stress shielding?)Reduction osteotomy
Difficult 1° THADifficult 1° THA
Small Patient
Difficult 1° THADifficult 1° THA
JRA, SED, dwarfAcet. & femoral dysplasiaTemplating criticalModular, custom,
mini componentsExpansion
osteotomy
Stenotic Femur
Avoid cement (stem too small)Cementless modularExpansion osteotomy
Difficult 1° THADifficult 1° THA
THA In Femoral Deformity
Diaphyseal
• Distal to implant
– Ignore deformity
– Treat independent of THA
THA In Femoral DeformityDiaphyseal
• Short implant or resurfacing
• Long implant / osteotomy
• Two stage (correct deformity, heal, THA)
THA In Femoral Deformity
• Individualize Management
– Level of deformity
– Type of deformity
– Bone quality
– Patient factors
– Surgeon preferences
Bone Defect Classification and Common Surgical Exposures
David A. Mattingly,MDChief, Joint Reconstruction
Director, Otto Aufranc FellowshipNew England Baptist Hospital
Boston,MA
Femoral Revision THA
Principles• Rotational implant stability
• Rigid implant fixation
• Stability with range of motion
• Restore Femoral Integrity & Continuity
• Prevent and/or Augment Bone Loss
• Restore Biomechanics (leg length; offset)
AAOS ClassificationFemoral Deficiencies
I. Segmental
II. Cavitary
III. Combined Segmental & Cavitary
IV. Malalignment
V. Stenosis
VI. Discontinuity
Paprosky Classification
Adequate Exposure in Complex THA
• Aids in Component Removal and Re-Insertion
• Accuracy of Instrument and Component positioning• Reduces incidence of fractures and perforations• Bone grafting procedures easier, faster, more accurate
Extensile Lateral
•Limitations: Post-column, Limitations: Post-column, retained trochanter, limp, retained trochanter, limp, H.O., lengtheningH.O., lengthening•retained trochanter, limp, H.O., lengtheningretained trochanter, limp, H.O., lengthening•Improved femoral exposureImproved femoral exposure•Reduces need for femoral fluoroscopyReduces need for femoral fluoroscopy•Perforations further weaken compromised femoral Perforations further weaken compromised femoral canalcanalIndicationsIndications
•Most complex THA’s Most complex THA’s •Less instabilityLess instability•SepsisSepsis•Postop irradiationPostop irradiation
Posterior
• Excellent exposure, minimal muscle damage, fast rehab
• Easy to make extensile
(soft tissue releases; femoral or trochanteric osteotomies)
• Retained trochanter limits distal canal access (>180 to 200 mm)
• Increased risk posterior dislocation
• Indications– Most acetabular/femoral revisions
– Posterior column plating
Complex THA
Trochanteric Osteotomy Advantages
• Allows extensile acetabular exposure (cages; posterior plating)
• Improves distal femoral access• Decreases fractures, perforations, varus• Assists in limb lengthening (>1.5 cm) and shortening
(5-10 mm)• Advancement improves M-F tension & stability
Extended Trochanteric OsteotomyIndications
• Well fixed implants (cement; porous)
• Well fixed cement
• Extensive Trochanteric Lysis
• Trochanteric Overhang/Varus Remodeling
• Malalignment Proximal Femur
Extended Trochanteric OsteotomyAdvantages
• Excellent exposure femur/acetabulum
• Atraumatic implant/cement removal
• Decreased perforations, fractures
• Deformity correction
• Protection of compromised trochanter
• Predictable healing
Distal Oblique Femoral Osteotomy
• Facilitates distal cement removal (>200 mm)
• Re-directional• 60o angle improves rotational
stability, maximizes contact, allows cerclage wiring
( Miller, et.al )
Retroperitoneal(Turner, Camer)
• Stage III - IV Protrusio
• Extruded medial cement
• IVP, venogram
• General, vascular surgeon