Total knee arthroplasty experience at the Robert Breck Brigham Hospital.

Between 1973 and 1978, 1,474 metal-to-plastic knee arthroplasties were evaluated to determine the typical modes of failure and improved design concepts (Table 2). Although the concepts are still evolving, and longer follow-up is necessary, recent experience with nearly 1,000 semiconstrained devices allowing cruciate retention strongly suggests that duopatella and kinematic design concepts are correct. Soft tissue reconstruction is critical with these designs, since they rely heavily on soft tissue integrity and balance. If the concepts of soft tissue balance, prosthetic design, and physical rehabilitation are applied, total knee replacement is as reliable in relieving pain and restoring function as total hip replacement. The low incidence of radiolucency at the bone-cement interface (although the length of follow-up is relatively short), coupled with the results of in vitro bench testing, suggest that the longevity of this generation of knee implants should be adequate.