Patellar button dissociation in a mobile-bearing LCS patellofemoral joint arthroplasty.

Patellofemoral arthroplasty is an effective treatment for isolated patellofemoral arthritis. Midterm results reveal a success rate of approximately 80% to 90% with modern designs. The reported failure mechanisms associated with patellofemoral arthroplasty include progressive tibiofemoral arthritis, patellar pain, catching or subluxation caused by soft-tissue imbalance, component malposition, and problematic designs. We present a previously unreported new complication of patellar button dissociation in a mobile-bearing LCS Patellofemoral Joint Replacement Prosthesis.