Survivorship and Clinical Outcomes up to Six Years After Combined Patellofemoral and Unicondylar Knee Arthroplasty

Abstract Background Due to improved technique and design, bicompartmental knee arthroplasty consisting of patellofemoral joint and unicondylar knee arthroplasty has become a promising alternative to total knee arthroplasty. Advantages include preserving natural knee biomechanics, reducing complication rates, shortening hospital stays, and facilitating faster rehabilitation. This study aimed to assess the survivorship and clinical outcomes for combined medial unicondylar and patellofemoral arthroplasty up to 6 years. Methods Data on survivorship and patient-reported outcome measures (PROMs) were analyzed retrospectively for 47 patients (mean age: 58.2 years [range: 45 – 78]; mean body mass index: 31.3 kg/m² [range: 22.8 – 47.3]; 66% female). The PROMs included pain (visual analog scale), knee functionality (Knee Injury and Osteoarthritis Outcome Score for Joint Replacement), mental and physical health (Veterans RAND 12-Item Health Survey), and patient satisfaction (Knee Society Score). Survivorship was analyzed using a survivorship life table, while changes in PROMs from preoperatively to the follow-up (FU) time points were assessed via paired t-tests. Results Of the 47 patients enrolled, 7 were lost to FU. The 97.8% survival rate remained consistent throughout the 6-year FU period, following 1 device-related revision within the first 2 years. There was a significant improvement in pain, knee functionality, and patient satisfaction from preoperative to the 1-, 3-, and 5/6-year FUs (P < .0001). Physical health significantly improved for all FU time points (P < .0001), while mental health trended toward improvement throughout the FU period. Conclusions The combined unicondylar and patellofemoral arthroplasty procedure has been shown to achieve excellent survivorship and clinical results up to 6 years after surgery. This makes it an attractive alternative to total knee arthroplasty for patients with medial condylar and patellofemoral knee osteoarthritis.