Abstract
Aim The primary objective of the study was to evaluate the mid-term implant survivability, rate of revisions, and clinical and functional outcomes following patella resurfacing during total knee arthroplasty (TKA) utilizing posterior stabilized (PS) total knee system (TKS). Methods A prospective, single-arm, multi-center, post-marketing surveillance encompassed patients with end-stage primary knee osteoarthritis (OA) or inflammatory arthritis. The time points of the study included baseline, six weeks, six months, one year, and three years post-operatively. Clinical outcomes included Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, Short Form-36 questionnaire (SF-36), and Knee Society Score (KSS) for quality of life (QoL). Radiographs assessed loosening, patella tracking, and implant longevity. Functional outcomes were assessed by range of motion (ROM). Result The study included 74 patients undergoing patella resurfacing during TKA with a PS all-poly component TKS at 10 centers in India. Among the study population, 85% were female, and the average age of the population was 65.13±7.20 years. End-stage OA (70 patients) and inflammatory arthritis (four patients) were the prevalent conditions. Patella sizes used were: 25 mm (n=1), 28 mm (n=29), 31 mm (n=40), and 34 mm (n=4). Primary outcomes showed implant survival was 100% with no revisions after three years. Local soft tissue infections and discomfort affected 3.2%, with no additional adverse events. Radiographs showed well-implanted patellar components with no misalignment or wear after three years. Secondary outcomes showed a significant three-year increase in mean ROM from 85.50°±15.02° to 122.45°±2.44°. After three years, clinical and functional KSS improved to 90.36±3.72 (baseline: 21.11±14.49) p<0.001 and 97.95±3.67 (baseline: 27.16±13.22) p<0.001, respectively. WOMAC values for pain, stiffness, and difficulty decreased significantly (p<0.001) over the three-year duration. SF-36 evaluating QoL showed substantial improvements (physical functioning, role limitation, and general health). Conclusion The study highlights the success of patella resurfacing during TKA, demonstrating excellent implant survival, improved functional outcomes, and QoL over a three-year period.