Reproducing the Mechanical Axis Did Not Improve the 15-Year Survival of 398 Modern Total Knee Arthroplasty

A fundamental premise of computer-assisted total knee arthroplasty (TKA) is that correcting the mechanical axis will promote implant durability. Only 1 publication has correlated postoperative limb alignment assessed on full-length x-rays with survivorship, and those authors used a knee implant substantially different from modern designs. With substantial resources being devoted to computer-assisted TKA, we decided to review, in a large group with full-length radiographs, the fundamental premise that correction of the mechanical axis predicts long-term durability of modern TKA.