Effect of posterior femoral condylar offset (PCO) on clinical results of multi-radius (MR) femoral design implant/component in posterior stabilized total knee arthroplasty (PS TKA)

Abstract

When a posterior condylar offset (PCO) is properly reconstructed in a Total Knee Arthroplasty (TKA), a larger posterior clearance can be achieved, which helps delay impingement posteriorly and maximizes the range of flexion (ROF). This study was conducted to investigate the effect of PCO on clinical outcomes using Multi-radius (MR) femoral design components in PS TKA. This hospital-based prospective observational study was conducted between January 1, 2018, and December 31, 2018, with a 6-month follow-up. A total of fifty patients were operated on with a MR PS design. The PCO, flexion, and knee society scoring (KSS) system were measured preoperatively and postoperatively.: The average age of the patients was 66.8 (range 58.3 to 75.3) years. The average preoperative and postoperative PCO was 27.5 (range 25.3 to 29.7) and 29.2 (range 26.2 to 32.2) mm, respectively. The average preoperative and postoperative non-weight-bearing flexion was 106.5 (range 93.7 to 119.3) and 119.9 (range 116.6 to 123.2) degrees, respectively. The average preoperative and postoperative weight-bearing flexion was 96.7 (range 86.6 to 106.8) and 123.6 (range 120.7 to 126.5) degrees, respectively. The average preoperative KSS knee score was 55.9 (range 52.6 to 59.2), and the average preoperative KSS function score was 29.4 (range 17.3 to 41.5). The average postoperative KSS knee score was 83 (range 80.5 to 85.4), and the average postoperative KSS function score was 83.2 (range 78.5 to 87.9). Among them, sixteen knees (32%) showed excellent KSS knee and function scores, while 34 knees (68%) showed good scores. There were statistically significant differences for all variables.: There was a significant increase in PCO, flexion (both weight-bearing and non-weight-bearing), KSS knee score, and function scores.