Insufficient Information to Determine Osteotomy Indication
The measurements you've provided (M PTA = 88.5° and L DFA = 83.5°) cannot determine whether knee osteotomy is indicated without a full-length standing hip-to-ankle radiograph showing the mechanical axis and weight-bearing line position.
Why These Measurements Are Inadequate
The gold standard for assessing lower limb alignment requires a standing full-length hip-to-ankle radiograph that provides accurate information on the weight-bearing mechanical axis, which is essential for evaluating malalignment and planning osteotomy 1, 2
Standard knee radiographs alone cannot accurately measure the mechanical axis needed for osteotomy planning 1
The hip-knee-ankle angle (HKA) measured on full-length weight-bearing radiographs is considered the gold standard for reliable and accurate measurement of the mechanical axis of the entire lower extremity 3
Critical Missing Information
To determine osteotomy indication, you need:
Mechanical axis deviation (MAD) - the distance from the weight-bearing line to the center of the knee 4, 3
Hip-knee-ankle angle (HKA) - the angle between the mechanical axes of the femur and tibia 3
Location of the weight-bearing line on the tibial plateau - specifically whether it passes through the medial or lateral compartment 4
Clinical correlation with symptoms, age, activity level, and degree of compartmental arthritis 5, 6
Standard Osteotomy Indications
Osteotomy around the knee is indicated for young to middle-aged patients with painful compartmental arthritis secondary to constitutional metaphyseal deformity in the frontal plane 7
Varus deformity with medial compartment overload typically requires valgus high tibial osteotomy 7
Valgus deformity with lateral compartment arthritis may require distal femoral osteotomy (for medium-large corrections) or medial closing wedge tibial osteotomy (for minimal deformities) 6