Archives of orthopaedic and trauma surgery
Postoperative alignment and patients reported outcome measures improvement after high tibial osteotomy: a significant interaction with osteoarthritis severity
By Itou J, Itoh M, Kuwashima U and 2 others.
Abstract
Purpose
Optimal postoperative alignment in high tibial osteotomy (HTO) remains controversial due to inconsistent target definitions and limited evidence supporting osteoarthritis (OA) severity-based strategies. This study evaluated clinical outcomes across postoperative weight-bearing line (WBL) categories stratified by OA severity, hypothesizing that overcorrection would be detrimental in early OA but not in advanced OA.
Methods
This retrospective single-center study included 181 knees that underwent open-wedge or closed-wedge HTO between 2017 and 2023 with a minimum 2-year follow-up. Knees were classified as early OA (Kellgren-Lawrence [KL] ≤ 2) or advanced OA (KL ≥ 3). The corrective angle was defined as the planned angular change required to shift the mechanical axis to the target postoperative alignment, determined by aiming for a postoperative %WBL of 62.5% on double-limb standing full-length radiographs. Overcorrection was defined as %WBL ≥ 70%. Clinical and radiographic outcomes were assessed at baseline and final follow-up. Multivariable regression models identified factors associated with changes (Δ) in Forgotten Joint Score-12 (FJS-12) and Knee Injury and Osteoarthritis Outcome Score (KOOS), and logistic regression evaluated achievement of minimum clinically important difference (MCID) and patient acceptable symptom state (PASS). Each knee was treated as an independent observational unit.