Eight to Ten Year Follow-Up Results of Total Knee Arthroplasty Using Electromagnetic Navigation System / 대한정형외과학회잡지

ABSTRACT

PURPOSE: The purpose of this study was to compare the clinical and radiological results between patients who underwent total knee arthroplasty using the conventional method and the navigation-assisted method. MATERIALS AND METHODS: A retrospective review of was performed on 32 patients (40 knees) who underwent total knee arthroplasty between February 2004 and December 2006 and were followed-up for 8 to 10 years. Mechanical axis deviation, range of motion, radiologic position of the implants, and subjective clinical scores were measured and compared between 20 navigation-assisted total knee arthroplasties and 20 conventional total knee arthoplasties. Change in the values (α, β, γ, and δ angles) from the immediate postoperative period to the last follow-up were also calculated and compared between the two groups. RESULTS: The mean range of motion in the navigation group was improved to 121.8°±16.3° (92°–140°) at the last follow-up, and the Western Ontario McMaster Universities osteoarthritis Index (WOMAC) score was 89.8±5.4 and the Knee Society score (KSS) was 91.5±7.5. The mean range of motion in the conventional group was 112.6°±25.6° (60°–140°) at the last follow-up. The WOMAC score was 84.2±10.6, and the KSS was 81.1±14.3. The α, β, γ, and δ angles of the implants were not significantly changed until the last follow-up. In the comparison between the two groups, only the mean range of motion (p=0.018) and the KSS (p=0.038) showed statistically better results in the navigation group than the conventional group. CONCLUSION: Navigation-assisted total knee arthroplasty showed better KSS and range of motion compared with the conventional group in a cross-sectional study with 8 to 10 years of follow-up results. However, only the KSS showed a significant difference between the two groups by the amount of changes in the clinical and radiological results.