Protective Lateral Hinge Wire in Opening Wedge High Tibial Osteotomy, Does gap size matter?

A retrospective study was conducted on 54 knees that underwent medial opening wedge high tibial osteotomy (MOWHTO) between 2021 and 2023 in Zagazig University hospitals. During each procedure, a protective wire was placed across the LH point before osteotomy. Patients were categorized into two groups based on wedge gap measures: Group І (gap <10 mm) and Group Ⅱ (gap ≥10 mm). Lateral hinge fractures (LHF) and wound complications were documented. Preoperative and postoperative evaluations at 6 months and 12 months included the Knee Society Knee score (KSKS) and Function Scores (KSFS), the Oxford Knee Score (OKS), and Health Survey short form questionnaire summary (SF-36) for the Physical (PCS) and Mental components (MCS). Results: The LHF incidence was relatively low in both groups, with group І having one case (3.7%) and group Ⅱ having 2 cases (7.4%). Each group experienced a single case of intraoperative LHF, both were type I. Postoperative fracture was discovered only in group Ⅱ (1 case). At the six-month mark, group І demonstrated better clinical scores than group Ⅱ, in KSKS (86.8± 16.8 vs. 74.2 ± 21.4, P = 0.029), the KSFS (74.6 ± 17.6 vs. 64.2 ± 20.6, P = 0.048), Oxford Knee Scores (37.8±8.9 vs. 34±8.7, P = 0.009), the PCS (67.9 ± 9.2 vs. 61.3 ± 11, P = 0.019 ), and MCS (70.3 ± 9.3 vs 65.8 ± 16.6, P =0.310). On the other hand, comparable clinical scores between the two groups were recorded at the 12-month follow-up (P > 0.05).