PAPER 171: MEDIUM-TERM RESULTS OF PATELLOFEMORAL JOINT ARTHROPLASTY: A MULTI-SURGEON, MULTI-IMPLANT STUDY

Abstract

Purpose: Isolated patellofemoral joint (PFJ) osteoarthritis has long been a common observation as an important source of knee pain. Once non-operative treatment modalities have been exhausted, the surgical options available are transposition/elevation of tibial tubercle, drilling, realignment procedures, patellectomy, patellar resurfacing, patellofemoral arthroplasty (PFA) and total knee arthroplasty (TKA). Among these, PFA is an established treatment of isolated PFJ osteoarthritis. We present our multi-surgeon, multi-implant series of patellofemoral joint arthroplasty performed over a 10 year period.

Method: This study was a retrospective review of all PFA performed in the Knee Arthroplasty Unit at our hospital over a ten year period from 1997 to 2006. The unit comprises seven specialist surgeons, each with considerable experience in knee arthroplasty and numerous trainee surgeons. One hundred and one PFA performed in 91 patients were identified from the theatre records. Three different implant models were used: the Lubinus implant (Waldemar Link), the FPV system (Wright Medical) and the Avon system (Stryker Howmedica Osteonics).

Results: 101 arthroplasties in 91 patients were followed up for average period of 48.8 months (6–96 months). Of these, none were lost to follow up. The average age was 57 years with female patients thrice as common as male patients. Concomitant procedures in the form of 23 lateral retinacular release or 6 osteochondral autograft transfer system (OATS) were performed. There were 6 complications with 2 infections and 4 stiff knees. 31 arthroplasties had subsequent procedures including arthroscopic debridement (18), arthroscopic lateral retinacular release (8), tibial tuberosity transfer (3) and manipulation for stiffness (2). A total of 4 arthroplasties underwent revision to total knee arthroplasty, 2 for infection and 2 for progression of tibiofemoral osteoarthritis.

Conclusion: The necessity of revision surgeries in one third of the cases suggests that close follow-up of the patients is needed to address any concerns that can be easily resolved. A majority of the patients in our study had very good outcomes and did not need subsequent procedures in the medium term. Our study reiterates the importance of proper patient selection, surgeon experience and correct surgical technique in successful outcomes from PFA.