Factors Affecting the Range of Motion after Revision Total Knee Arthroplasty

ABSTRACT

PURPOSE: We aimed to analyze the clinical results and investigate the factors that affect the range of motion (ROM) after revision total knee arthroplasty. MATERIALS AND METHODS: We measured the range of motion from 61 knees of 55 patients who underwent revision total knee arthroplasty using the Nexgen(R) LCCK and we investigated the factors affecting the postoperative ROM, including age, the body mass index (BMI), the preoperative ROM, deformity, causes of revision (septic vs. aseptic) and the type of polyethylene inserts (constrained vs. posterior-stabilized). The clinical results and radiographic findings were assessed using the American Knee Society Score and the roentgenographic method of the American Knee Society. RESULTS: The mean range of motion was improved from 113.7degrees to 127.2degrees. The preoperative ROM (p=0.000) and diagnosis (p=0.006) significantly influenced the postoperative ROM, yet age (p=0.386), BMI (p=0.054), deformity (p=0.218) and the type of polyethylene insert (p=0.195) were not related to the postoperative knee ROM. The American Knee Society Knee Score and Function Score on average was improved from 31.7 and 27.9 points to 86.7 and 64.7 points, respectively. CONCLUSION: The range of motion and clinical results were satisfactory after revision total knee arthroplasty using the Nexgen(R) LCCK, and the important factors affecting the range of motion after operation were the preoperative ROM and the causes of revision. The range of motion after arthroplasty using the constrained type polyethylene insert was not inferior to that using the posterior-stabilized insert.