Factors affecting articular cartilage repair after open-wedge high tibial osteotomy

Abstract Purpose To evaluate the factors that affect articular cartilage repair after open-wedge high tibial osteotomy (OWHTO) and the relationship between regeneration of articular cartilage repair and clinical outcomes. Methods Among the cases of OWHTO that were performed from March 2005 to February 2012, the patients who followed up for > 2 years and received a second-look arthroscopy were retrospectively reviewed. For clinical evaluation, the Knee Society scores and Western Ontario and McMaster Universities Osteoarthritis Index score were measured. For radiologic evaluation, the Kellgren-Lawrence scale, mechanical femorotibial angle, and joint line obliquity were used. In the initial and second-look arthroscopy, the status of the articular cartilage of the medial compartment was evaluated. Results A total of 62 knees (61 patients) were included in this study. Articular cartilage repair was observed in 18 knees (29.0%). In multiple logistic regression analysis, patients with Kellgren-Lawrence Grade 4 (OR 0.076; 95% CI 0.007–0.822; P = 0.034), the existence of a bipolar lesion (OR 0.108; 95% CI 0.016–0.724; P = 0.022), or joint line obliquity > 5º (OR 0.109; 95% CI 0.013–0.936; P = 0.043) had significantly lower odds of articular cartilage repair compared to the corresponding counter group. In a comparison of clinical outcomes between a group that had articular cartilage repair and a group without repair, no significant difference was observed ( P > 0.05). Conclusions Severe arthrosis, existence of a bipolar lesion, and marked postoperative joint line obliquity had a negative impact on articular cartilage repair after OWHTO. However, articular cartilage repair showed unknown clinical significance.