Comparison of Two Methods of Patellar Resurfacing in Total Knee Arthroplasty.A Prospective, Randomized, Double-blind Study

With improved surgical techniques and implant designs, patella resurfacing has been favored by increasing surgeons. When performing the resection, several principles such as restoring the original patellar thickness, avoiding over or under resection must be complied in order to achieve satisfactory outcomes.This study was conducted to compared the outcomes of two commonly adopted methods for performing patellar resection in total knee arthroplasty. One hundred patients with osteoarthritis were recruited in the clinical trial using Nexgen Legacy Posterior Stabilized-Flex prosthesis. Patients were randomized to receive "free-hand" technique and "resection guide" technique when performing patellar resection in total knee arthroplasty. Patients were evaluated preoperatively and at follow-up visits conducted at twelve months, at twenty-four months. Clinical outcome was assessed and compared with use of the visual analogue pain scale (VAS), range of motion, Knee Society Score (KSS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and the Short Form-36 (SF-36). Patellar alignment was assessed before surgery and at each follow-up by measuring the patellar tilt (PT) and lateral patellar displacement (PD). Prosthetic position and leg alignment were also compared between the two groups.