Vancomycin-soaked femoral head allograft in opening wedge high tibia osteotomy enables earlier postoperative recovery and reduces infection rates compared to allogenic bone chips.

Abstract

To investigate the benefits of vancomycin-soaked femoral head allograft versus allogenic bone chips as an osteotomy gap filler in reducing infection rates and perioperative pain control after medial opening wedge high tibial osteotomy (MOW-HTO). Retrospective analysis of 114 knees that underwent MOW-HTO between 2013 and 2020. Osteotomy gaps were filled with vancomycin-soaked femoral head allograft (Study Group) or allogenic bone chips (Control Group). Both groups received systemic antibiotics. Perioperative parameters studied included pain, blood loss, length of stay, postoperative day (POD1) pain scores at rest, with activity as well as ambulatory distance. Patients in the Study Group were also followed up prospectively and clinical outcome scores, namely Knee Society Score, Oxford knee score (OKS) and Physical and Mental Component of the Short-Form 36 Questionnaire (PCS and MCS, respectively). Statistical analyses using Student's T-test were performed between the groups. Patients of the study group had significantly better POD1 visual analogue scale (VAS) at rest (0.9 ± 1.6 vs 2.9 ± 1.2, p < 0.001) as well as when active (3.0 ± 1.9 vs 5.8 ± 1.5, p < 0.001). A greater proportion of patients in the study group ambulated on POD 1, (90.6% vs 26.0%, p < 0.001). Of those who ambulated on POD1, study group patients managed to cover a greater ambulatory distance (13.9 ± 7.4m vs 8.4 ± 9.3m, p < 0.05). The proportion of study group patients requiring patient-controlled analgesia (PCA) was also significantly less compared to the control group (32.8% vs 58.0%, p < 0.05). Of those requiring PCA, the amount of morphine requirement was also significantly reduced in the group with vancomycin-soaked allograft (8.7 ± 8.1mg vs 23.9 ± 33.0mg, p < 0.05). The study group also had a reduced length of stay (3.5 ± 2.0days vs 5.5 ± 2.6days, p < 0.001). Patients in the study group demonstrated significant improvement in Knee Society Knee Score (KSKS), OKS, PCS and MCS at 12months postoperatively. The study group had a significantly reduced incidence of superficial wound infections compared to the control group (3.1% vs 18.0%, p < 0.05). Vancomycin-soaked femoral head allograft reduced superficial and deep wound infections in MOW-HTO. It was also effective in reducing postoperative pain, thereby enabling early ambulation and shorter hospital stays. Retrospective comparative study, III.