Alignment of total knee arthroplasty

A series of 65 total knee arthroplasties performed by the senior author was evaluated to determine the effect of alignment on outcome. Radiographs and results of clinical examination were reviewed. Sixty-one of the 65 knees were in varus on the mechanical axis (ie, the weight-bearing line passed through the medial compartment). At an average follow-up period of 48 months, alignment was not found to affect incidence or progression of radiolucent lines, changes in tibial metaphyseal density, or clinical outcome (pain or range of motion). The authors were unable to confirm the historical belief that alignment is critical to the durability of cemented total knee arthroplasty, nor that the mechanical axis must pass through the center of the knee joint.