The Combination of Inlay Patellofemoral Arthroplasty and Medial Unicompartmental Knee Arthroplasty Versus Total Knee Arthroplasty for Mediopatellofemoral Osteoarthritis: A Comparison of Mid-Term Outcomes

Background: To the best of our knowledge, there have been no studies in the literature related to the use of second-generation inlay patellofemoral arthroplasty and unicompartmental knee arthroplasty combination (inlay PFA/UKA) in the treatment of mediopatellofemoral osteoarthritis (MPFOA). The aim of this study is to evaluate the efficacy of inlay PFA/UKA in MPFOA. Methods: The study included 49 patients applied with inlay PFA/UKA because of MPFOA and 49 patients applied with TKA, matched one-to-one according to age, gender, body mass index, follow-up period, preoperative Knee Society Score, and range of motion. All the patients were evaluated clinically using the Knee Society Score, Knee Injury Osteoarthritis Outcome Score, and range of motion, and were also evaluated radiologically. Complication rates and length of hospital stay were compared. Results: The mean follow-up period was 54 +/- 4 and 54.4 +/- 3.9 months in inlay PFA/UKA and TKA groups, respectively. (P = .841). No statistically significant difference was determined between the 2 groups in respect of the mean clinical scores at the final follow-up examination (P >= .129). Total complications were fewer and length of hospital stay was shorter in the inlay PFA/UKA group than in the TKA group (P = .037 and P = .002). There was no radiographic evidence of progression of lateral compartment osteoarthritis according to Kellgren-Lawrence in any patient in the inlay PFA/UKA group. Conclusion: In selected patient groups, inlay PFA/UKA is an alternative to TKA, with lower complication rates, shorter length of hospital stay, and clinical and functional results similar to those of TKA without osteoarthritis progression in the unresurfaced lateral compartment in the mid-term. (C) 2019 Elsevier Inc. All rights reserved.