Total Knee Replacement in Severe Varus Knees

Abstract

Background: Varus deformity is predominantly the commonest deformity in candidates for total knee arthroplasty. Obtaining a well-positioned and stable prosthetic construct with restoration of the normal mechanical axes of the limb and joint line have been shown to have an important bearing on the final outcome of knee replacement operations. Objective: The aim of this work is to study the results and outcome of total knee replacement in severe varus knees and how to manage the ligamentous laxity and bone defect to improve the alignment of the limb. Patients and methods: This study was carried out in the period between January, 2016 and July, 2019. A prospective study was conducted involving 32 patients with 40 knees with a severe varus deformity, indicated for total knee arthroplasty. The implants used for these cases are total knee, however PCL sacrificing or CCK were used, according to the knee problem, the condition of the ligaments and the bone defect. Results: The results of our study showed that the average knee society score (KSS) showed a highly significant increase postoperatively to be 93.0±4.5 in compared with average preoperative KSS of 30.2±15.0. The average knee function score at the last follow up was 75.3+10.0 (range from 65 to 80) compared with average preoperative knee 25.7+20.1 (range from 5 to 40). Conclusion: Sequential medial soft tissue release must be performed to provide adequate stability without over releasing. PCL must be released in severe fixed varus deformity especially if accompanied by flexion deformity.