Comparison of Functional Outcome of Total and Unicompartmental Knee Arthroplasty Using Computer-Assisted Patient-Specific Templating

Abstract

Background. Knee arthroplasty surgeries are in ever-increasing demand. With unicompartmental knee arthroplasty (UKA), patients may benefit from a higher range of flexion and a better Knee Society Score (KSS). Aim. In this study, we compared the short-term clinical outcomes of total knee arthroplasty (TKA) and UKA using the patient-specific templating (PST) technique. Methods. Two groups of 20 knees each were divided into UKA and TKA groups depending on the Oxford criteria of UKA. Only patients with medial compartmental osteoarthritis were included. KSS, functional knee score (FKS), and ROF were assessed preoperatively and at 6 months postoperatively. Results. The TKA group has shown a significant improvement compared to the UKA group in KSS (MD = 39.35 vs. 31.2, respectively, $p=0.003$ ). Both TKA and UKA have shown no significant difference concerning both the FKS (MD = 32 and 31.75, respectively, $p=0.926$ ) and ROF (MD = 10.25 and 7.25, respectively, $p=0.072$ ). Discussion. The higher improvement of KSS in the TKA group can be attributed to the fact that patients in the TKA had significantly worse KSS preoperatively. Also, the small improvement in ROF in the UKA group might be related to their wider preoperative ROF. Conclusion. Preoperatively, the TKA group had lower KSS and ROF compared to UKA. The improvement of KSS from preoperative to postoperative was more significant in TKA. However, the TKA group has shown less range of flexion postoperatively.