Excellent Short-Term Outcomes After Kinematic Alignment, Medial-Pivot Total Knee Arthroplasty for Isolated Patellofemoral Osteoarthritis

Background: The optimal treatment for isolated patellofemoral osteoarthritis (PFOA) remains controversial. Operative management for PFOA includes patellofemoral arthroplasty; however, concerns regarding tibiofemoral disease progression and high revision rates limit its use. Total knee arthroplasty (TKA) is another treatment option, but comparative outcomes between patients with isolated PFOA and those with tibiofemoral osteoarthritis (TFOA) undergoing TKA are not well established. This study compared postoperative outcomes in these 2 populations, hypothesizing that patients with isolated PFOA treated with TKA will achieve similar results to those with TFOA. Methods: A total of 378 consecutive patients with isolated PFOA (n = 17) and TFOA (n = 361) underwent primary unrestricted caliper-verified kinematic alignment TKA with medial-pivot implants. Patients completed the Forgotten Joint Score, Knee Injury and Osteoarthritis Outcome Score (KOOS-JR), and Knee Society Score (KSS) at preoperative, 6-week, 6-month, and 1-year postoperative visits. Extension and flexion were measured at those visits. All outcome measures equalized between groups at 6 months and 1-year postoperative. Conclusions: Within the limits of the available sample size, patients with isolated PFOA achieved comparable 6-month and 1-year outcomes to those with TFOA following kinematic alignment-TKA with medial-pivot implants, supporting its use as an effective treatment option. Level of Evidence: III.