Abstract
Total knee arthroplasty using navigation system is known to be more effective than conventional methods in achieving more accurate bone resection and neutral alignment. Mobile bearing is also known to reduce wear and automatically correct rotational mal-alignment of the tibia but the long-term follow-up results of more than 10 years are extremely rare. The purpose of this study is to investigate the results of clinical and radiologic long-term follow-up and complications of total knee arthroplasty using navigation and multi-directional mobile bearing.
From 2003 to 2006, a total of 111 navigation TKAs using multi-directional mobile bearing design were carried out and reviewed retrospectively. TKAs were performed by two experienced surgeons at one institute. Of the 111 patients, 102 were women and 9 were men. The mean duration of follow-up was 11.4 ± 1.0 years (range, 10.1 to 14.08 years). Clinical outcomes were evaluated in terms of Knee Society Score, Hospital for Special Surgery score, Western Ontario and McMaster University (WOMAC) score, range of motion and complications. Long-term radiological outcomes and survival rates were evaluated at least 10 years.
Average preoperative HSS score was 66.5 ± 9.8 and KSS pain and function score were 25.0 ± 11.8 and 44.5 ± 12.3, respectively. Scores improved to 94.1 ± 8.2, 46.6 ± 11.6 and 88.2 ± 14.6 at the last follow up, respectively. Mean preoperative WOMAC scores of 75.8 ± 16.5 improved to 13.8 ± 16.0 at last follow-up. Five knees required re-operation, two for liner breakage for liner wear, one for distal femoral fracture and one for infection. The estimated 10-year prosthesis survival rates for any reason and for prosthesis-related problems were 95.5% and 97.4%, respectively. TKAs using each techniques resulted in similar good clinical outcomes and post-operative leg alignments. Robotic and navigation TKA appeared to reduce the number of postoperative leg alignment outliers and revision rate compared to conventional TKA.