Clinical outcomes of hybrid closed-wedge high tibial osteotomy according to the Kellgren-Lawrence grade.

Abstract

Hybrid closed-wedge high tibial osteotomy (HCWHTO) may yield favorable outcomes even for advanced knee osteoarthritis (OA). We investigated the relationship between preoperative radiographic OA severity and postoperative clinical outcomes and the relationship's impact on HCWHTO. We analyzed the cases of 65 patients who underwent an HCWHTO (2018-2024) at our institution. The pre- and postoperative Knee Injury and Osteoarthritis Outcome Score (KOOS), Tegner Activity Scale (Tegner score), and Lysholm score were identified. Radiographic OA severity was based on the Kellgren-Lawrence (KL) grades; we divided the patients into KL-2, KL-3, and KL-4 groups and compared the clinical outcomes between the pre- and postoperative periods and across groups. A multivariate linear regression analysis investigated factors associated with postoperative clinical scores. The mean age was 59.7 years (range, 41-79), and the mean follow-up period was 38 months (range, 24-84). The clinical outcomes improved significantly after HCWHTO in all three KL groups. Compared to the KL-2 patients, the KL-4 patients showed significantly lower KOOS Symptoms (p = 0.0045), Pain (p = 0.0135), ADL (p = 0.0131), and Lysholm (p = 0.0125) scores. The multivariate regression analysis identified higher KL grade as independently associated with worse postoperative KOOS Symptoms (β = -0.36, p = 0.0177), Pain (β = -0.35, p = 0.0342), and ADL scores (β = -0.39, p = 0.0095). Although post-HCWHTO outcomes were inferior in patients with KL-4 versus KL-2 patients, significant clinical improvement was observed regardless of the KL grade. Since KL grade progression adversely affects postoperative outcomes, careful patient selection based on age and activity level remains necessary.