抄録
Total knee arthrosplasty (TKA) is commonly used as a treatment for end stage varus osteoarthritis of the knee. However, since almost all the patients are elderly subjects with medical complications, TKA has to be avoided in some of these patients because of surgical risk. We performed arthroscopic medial release (AMR) in patients not indicated for major surgeries.
Fifteen knees of 9 patients with end stage varus osteoarthritis of the knee, who underwent AMR from July 2000 and were followed for over 18 months, were studied. There were 8 females and 1 male aged from 72 to 81 years (mean age 75.2 years) . According to radiologic evaluation, all cases were Kellgren and Lawrence grade N, with femorotibial angles ranging from 184°to 191° and averaging 187.9°. The follow-up period ranged from 23 to 33 months and averaged 26.2 months.
AMR was performed by the following method. Under arthroscopy, the medial articular capsule and medial collateral ligament were cut transversely until the medial articular gap was sufficiently enlarged. After surgery, a hard brace for varus knee was worn and full weight bearing was started the next day after surgery.
The knees were evaluated using a visual analog scale (VAS; a self-scored scale with the normal knee taken as 100) and Japanese Orthopedic Association (JOA) score before and after surgery, Next, based on a diagnosis of end stage knee osteoarthritis, the surgical results of AMR were compared with the surgical results of 14 knees of 11 patients who underwent high tibial osteotomy (HTO) and 12 knees of 10 patients who underwent TKA, and the indication of AMR was evaluated. Statistical analysis of differences was performed using a t-test.
For AMR, the VAS score was 32.5 before surgery and improved significantly to 58.3 after surgery. The mean JOA score also increased from 58.2 before surgery to 66.4 after surgery, but the improvement was not statistically significant. On the other hand, the treatment results of AMR (VAS and JOA scores) were significantly lower than those of HTO and TKA. Patient satisfaction could be assessed in patients evaluated as significantly improved by VAS after AMR, and the satisfaction was significantly poorer than TKA and HTO. Based on these findings, the indication for AMR is judged to be end stage varus osteoarthritis of the knee that cannot undergo major invasive surgeries such as TKA due to severe medical complications.
