Reliable improvements in participation in low-impact sports following implantation of a patellofemoral inlay arthroplasty at mid-term follow-up

PURPOSE: The aim of this study was, to investigate the rate of return to sports (RTS) and physical activity after implantation of PFIA and to identify factors predictive of improved postoperative sporting ability. METHODS: Sixty-two patients with a mean age of 46 ± 11 years, who underwent implantation of PFIA at the senior authors’ institution, were enrolled. They were prospectively evaluated preoperatively and at a minimum of 2 years postoperatively with a mean follow-up of 60 ± 25 months. Clinical outcomes, return to sports and activity, type of sport or activity, subjective satisfaction, and frequency were evaluated by questionnaire. RESULTS: The transformed overall Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score improved from 67 ± 16 to 77 ± 19 (p = 0.003), Tegner activity scale results improved from 3 ± 2 points to 4 ± 1 points (p < 0.001), and scores on the visual analog scale (VAS) pain scale decreased from 6 ± 2 points to 3 ± 2 points (p < 0.001). The sports frequency increased from 1 ± 2 sessions to 2 ± 1 sessions per week (p = 0.001). Ninety-four percent of the patients who did not fail could return to the same or higher level of sports, with 74% of the patients reporting an improved ability to perform sports. No preoperative factors could be detected to significantly influence RTS after surgery. CONCLUSIONS: PFIA is a valid treatment option for the active patient with end-stage isolated patellofemoral OA. Reliable improvements in knee function, pain, and participation in low-impact sports were found. LEVEL OF EVIDENCE: IV.