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Varus Femoral Osteotomy Surgical technique, tips and pearls
William Bugbee, MD
Scripps Clinic, La Jolla CA
38 year old woman previous
ACL(s), lateral MAT, OCA
Why Osteotomy?
• Simple procedure
• Biologic solution
• Preserves integrity of joint
• Amenable to conversion to
arthroplasty
• No implant related activity
restrictions
• Favorable clinical outcome
data
How important is osteotomy in the
context of joint restoration?
• Little objective data
– Small series, short term follow-up
– RPT unlikely to be performed
– Multivariate analysis will make it difficult to define
contribution of osteotomy
– Anecdotal evidence
• Experienced surgeons are utilizing osteotomy
more frequently in their cartilage repair
algorithms
Distal Femoral Varus Osteotomy
for Valgus Deformity
• Much less commonly performed
(my favorite)
• Lateral compartment arthritis
• Cartilage, meniscus or ligament
repair in valgus knee
• Valgus deformity with joint
instability
• Alternative to MAT?
Radiographic Evaluation
• Full limb (51”) standing radiographs
Lower Extremity Alignment Anatomy and Terminology
• Dror Paley: Principles of Deformity Correction (Springer, 2002)
• Mechanical axis (weight bearing line)
• Anatomic axis (tibiofemoral angle)
• Distal femoral angle
• Proximal tibial angle
• Joint line angle
• Mechanical axis deviation
• Frontal vs. sagittal plane (tibial slope)
Mechanical Alignment Test Paley, 1992
• Measure mechanical axis
deviation
• Measure distal femoral
angle (85-90)
• Measure proximal tibial
angle (85-90)
• Measure joint line angle
(0-2)
• Rule out subluxation and
condylar malalignment
Pathoanatomy of the Valgus Knee
• Very different from varus knee
• Lateral femoral condyle dysplasia
• Excessive distal femoral valgus
• Often associated with patellofemoral pathology
• Loss of lateral meniscus function
• Medial ligament laxity
• Lateral ligament contracture
• Often worse clinically than radiographically: must watch patients stand and walk!
Femoral Osteotomy Technique
• Deformity is usually
excessive distal
femoral valgus
• Femoral side to
prevent joint line
obliquity
• Medial closing wedge
with blade plate
• Lateral opening
wedge with plate
Opening Wedge Osteotomy
Technique • Very simple
• “mini-incision”
• Extra articular
• One bone cut
• Familiar plate and screw fixation
Changes in Sagittal Plane
• Usually a technical
error!
• HTO: Inadvertent
increase in tibial slope
• DFO: inadvertent
femoral flexion
– Afraid of the back of
the knee
– Inferior visualization
Opening Wedge DFO Outcome
• 40 knees mean age 37
• Mean 5 year f/u (2-12)
• IKDC improved from 36 to
62
• 74% survivorship for OA
• 92% survivorship in
cartilage repair
Distal Femoral Osteotomy
• Useful in managing lateral compartment arthritis, cartilage and meniscal deficiency
• Modern technique is simple and reproducible
• Favorable clinical outcome (better than HTO)
• Allows high activity level
• Easily convertible to arthroplasty
• Always consider it in the valgus knee or in patients without functioning lateral meniscus, even if deformity is small
Thank You