Patellofemoral arthroplasty in the treatment of patellofemoral arthritis: rationale and outcomes in younger patients.

Patellofemoral degenerative disease encompasses a spectrum of articular wear from severe chondrosis to advanced arthrosis. The rationale and timing for many operative approaches currently advocated for the relief of symptomatic patellofemoral degeneration can be the subject of intense surgical debate in any one patient. Unfortunately, the limited efficacy of many commonly advocated operative procedures has left a legacy of patellofemoral disability in many younger individuals. While total knee arthroplasty has an established role in the treatment of advanced patellofemoral arthritis in the older patient (age >60 years), the performance of what some have called "a knee joint amputation" in younger patients (age <45 years) remains controversial and less acceptable to patients. The Avon patellofemoral prosthesis is a second-generation knee joint-conserving device that has consistently achieved good to excellent results in both the primary treatment and salvage of patellofemoral degenerative disease in younger patients. In addition, patellofemoral arthroplasty has demonstrated success as a unique functional, tibial-femoral joint-conserving solution in a variety of other patellofemoral extensor mechanism problems.