Comparing open and closed wedge high tibial osteotomy in osteoarthritis of medial compartment of the knee

Background: High tibial osteotomy is an accepted procedure to reduce the progress of osteoarthritis of medial compartment of the knee and also to decline the patient’s complaints such as pain or limitation of physical activities. Objective: The aim of this study was to compare two methods of lateral closed wedge and medial open wedge in osteoarthritis of medial compartment of the knee. Methods: This study was a prospective clinical trial, performed on 59 patients (37 females and 22 males) at Rasul-e-Akram Hospital in Tehran during 2006 and 2008. The mean follow-up time of the patients after surgery was 27±6 months. Femorotibial angle, pain, joint’s function as well as limitation of motion, total score of Lysholm criteria, and stability of the medial collateral ligament were assessed and recorded before and after surgery. Data were analyzed statistically using Chi-square test, t-test, and Mann-Whitney test. Findings: The angles of correction were 9.8 and 9.6 in closed and open wedge, respectively. Seven cases (24.1%) of post-surgery complications were seen in closed wedge and 8 cases (21.1%) in open one among those 4 cases in closed and only 1 case in open wedge needed reoperation. The mean times of the healing process were 3.1±1.7 and 2.8±1.2 months after closed and open wedge osteotomy, respectively. There was no significant difference between two methods. Both methods resulted in remarkable decrease in pain along with increased function and Lysholm score after surgery yet no significant distinction was demonstrated between two techniques. In addition, while the stability of medial collateral ligament considerably increased in open wedge method, it slightly decreased in closed wedge technique following surgery. Conclusion: Considering the increased stability of medial collateral ligament by open wedge method and slight instability after closed wedge method, it seems that the instability of the medial collateral ligament before surgery to be one of the most noteworthy indications of medial open wedge osteotomy.