Good clinical outcomes of patellofemoral arthroplasty for isolated patellofemoral osteoarthritis: a case-matched cohort comparative study of PFA with TKA

Abstract

Background: Severe isolated patellofemoral osteoarthritis is usually treated by total knee arthroplasty (TKA) in the majority of the world but patellofemoral arthroplasty (PFA) has been a viable alternative for many years although there have been concerns about implant longevity. The purpose of this research was to compare the clinical outcome of patients with isolated patellofemoral osteoarthritis who received PFA or TKA. Methods: From January 2015 to December 2017, 42 patients with isolated patellofemoral osteoarthritis who received PFA were included in the PFA group. In this period, a matched cohort of 42 patients with isolated patellofemoral osteoarthritis who received TKA (TKA group) was chosen for comparison. The results of the two groups were compared before surgery and at last follow-up using Tegner Activity Scale, Range of motion of the knee, Oxford Knee Score and Short Form 36 Health Survey. Differences were considered statistically significant at p < 0.05.Results: The mean follow-up time was 3.5 ± 0.3 and 3.4 ± 0.3 years in the PFA and TKA groups (p = 0.13), respectively. No significant difference in preoperative knee scores were found between the two groups (p > 0.05). However, postoperative, compared with Tegner Activity Scale, Range of motion, Oxford Knee Score and Short Form 36 Health Survey, the PFA group performed significantly better results (p < 0.05). The Kaplan-Meier implant survivorship with 95% confidence intervals was 94.12 % in the PFA group and 94.74% in the TKA group (p = 0.49).Conclusions: The patients with isolated patellofemoral osteoarthritis who underwent PFA had shown better clinical outcomes and higher quality of life. We believed that for the treatment of isolated patellofemoral osteoarthritis, the PFA was a less invasive procedure with improved patient satisfaction and range of motion at medium term follow-up.