The 0-3-6-9 Rule in Mechanical Alignment Total Knee Arthroplasty (MA-TKA)

The goal of MA-TKA is to restore the normal mechanical axis. In contrast to kinematic axis alignment, which attempts to recreate native knee joint line (3° tibial varus and 3° femoral valgus), in MA-TKA, the distal femur and the tibia are cut to be perpendicular (0°) to the mechanical axis....

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