Varus Femoral Osteotomy - Amazon S3...Pathoanatomy of the Valgus Knee •Very different from varus...

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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