Abstract：
OBJECTIVE: This study investigates the effect of the body mass index (BMI) on the early (2 years) to midterm (5 years) results of medial opening wedge high tibial osteotomy (MOWHTO).
METHODS: A prospectively maintained single-centre database of 1138 knee osteotomies, between 2002 and 2022, was retrospectively reviewed. Adult patients who underwent MOWHTO for symptomatic unicompartmental medial knee osteoarthritis (OA), with varus knee malalignment, having failed conservative management, were included. Patients were categorized into three groups according to their BMI as per the classification from the National Institute for Health and Care Excellence (NICE): the healthy weight (HW) group (BMI of 18.5-24.9 kg/m2), the overweight (OW) (BMI of 25-29.9 kg/m2), and the obesity (OB) group (BMI ≥ 30 kg/m2). Multiple patient-reported outcome measures (n = 6) were recorded preoperatively and at 2 and 5 years postoperatively. Deformity analysis was undertaken preoperatively and postoperatively. The relative risk (RR) of the complications between the HW, OW and OB groups was calculated. The rate of conversion to arthroplasty, and 5 and 10 years survivorship were recorded, as well as the hazard ratio (HR) of BMI on survivorship.
RESULTS: A total of 574 cases were included in the study: the HW group (n = 96), the OW group (n = 233) and the OB group (n = 245), with a mean BMI of 23 ± 1.5 kg/m2, 27.4 ± 1.4 kg/m2 and 34.4 ± 3.8 kg/m2, respectively. The mean follow-up was 13.3 years (4.8-20.3). The mean mechanical tibiofemoral angle corrections were in the HW group: 7.1 ± 3°, OW group: 6.6 ± 3.5° and OB group: 7.1 ± 3.8°, with no intergroup significant difference (p = n.s.). Clinically, despite lower preoperative scores in the OW and OB groups, no difference was observed postoperatively amongst the three groups. The overall complication rate was 12.5% in the HW group, 6.8% in the OW group, and 9.8% in the OB group. There was no significant difference in the RR of complications between the HW and OW groups (RR = 0.6, 95% confidence interval [CI] = 0.3-1.3) (p = 0.2), and the HW and OB groups (RR = 0.8; 95% CI = 0.3-2.2) (p = 0.7). There was no overall significant difference in survival outcomes based on the BMI between the three groups (p = 0.4). The HR of conversion to arthroplasty between the HW and OW groups was 1.4 [95% CI = 0.6-3.5](p = 0.5) and between the HW and OB groups was 1.8 [95% CI = 0.8-4.4] (p = 0.2).
CONCLUSIONS: BMI has no significant effect on either the radiological corrections, clinical outcomes, complications or survivorship of MOWHTO at short- to medium-term follow-up. No specific cutoff point for BMI can be recommended as a contraindication to MOWHTO.
METHODS: Level IV, Retrospective cohort study.
METHODS: A prospectively maintained single-centre database of 1138 knee osteotomies, between 2002 and 2022, was retrospectively reviewed. Adult patients who underwent MOWHTO for symptomatic unicompartmental medial knee osteoarthritis (OA), with varus knee malalignment, having failed conservative management, were included. Patients were categorized into three groups according to their BMI as per the classification from the National Institute for Health and Care Excellence (NICE): the healthy weight (HW) group (BMI of 18.5-24.9 kg/m2), the overweight (OW) (BMI of 25-29.9 kg/m2), and the obesity (OB) group (BMI ≥ 30 kg/m2). Multiple patient-reported outcome measures (n = 6) were recorded preoperatively and at 2 and 5 years postoperatively. Deformity analysis was undertaken preoperatively and postoperatively. The relative risk (RR) of the complications between the HW, OW and OB groups was calculated. The rate of conversion to arthroplasty, and 5 and 10 years survivorship were recorded, as well as the hazard ratio (HR) of BMI on survivorship.
RESULTS: A total of 574 cases were included in the study: the HW group (n = 96), the OW group (n = 233) and the OB group (n = 245), with a mean BMI of 23 ± 1.5 kg/m2, 27.4 ± 1.4 kg/m2 and 34.4 ± 3.8 kg/m2, respectively. The mean follow-up was 13.3 years (4.8-20.3). The mean mechanical tibiofemoral angle corrections were in the HW group: 7.1 ± 3°, OW group: 6.6 ± 3.5° and OB group: 7.1 ± 3.8°, with no intergroup significant difference (p = n.s.). Clinically, despite lower preoperative scores in the OW and OB groups, no difference was observed postoperatively amongst the three groups. The overall complication rate was 12.5% in the HW group, 6.8% in the OW group, and 9.8% in the OB group. There was no significant difference in the RR of complications between the HW and OW groups (RR = 0.6, 95% confidence interval [CI] = 0.3-1.3) (p = 0.2), and the HW and OB groups (RR = 0.8; 95% CI = 0.3-2.2) (p = 0.7). There was no overall significant difference in survival outcomes based on the BMI between the three groups (p = 0.4). The HR of conversion to arthroplasty between the HW and OW groups was 1.4 [95% CI = 0.6-3.5](p = 0.5) and between the HW and OB groups was 1.8 [95% CI = 0.8-4.4] (p = 0.2).
CONCLUSIONS: BMI has no significant effect on either the radiological corrections, clinical outcomes, complications or survivorship of MOWHTO at short- to medium-term follow-up. No specific cutoff point for BMI can be recommended as a contraindication to MOWHTO.
METHODS: Level IV, Retrospective cohort study.
摘要：
目的：本研究调查了体重指数（BMI）对内侧开窗楔形胫骨高位截骨术（MOWHTO）早期（2年）至中期（5年）结果的影响。
方法：前瞻性维护的1138例膝关节截骨术单中心数据库，在2002年至2022年之间进行了回顾性审查。接受MOWHTO治疗有症状的单室内侧膝骨关节炎（OA）的成年患者，膝盖内翻畸形，保守管理失败，包括在内。根据国家健康与护理卓越研究所（NICE）的分类，根据BMI将患者分为三组：健康体重（HW）组（BMI为18.5-24.9kg/m2），超重（OW）（BMI为25-29.9kg/m2），和肥胖（OB）组（BMI≥30kg/m2）。术前以及术后2年和5年记录了多个患者报告的结果指标（n=6）。术前、术后进行畸形分析。HW之间并发症的相对风险(RR)，计算OW和OB组。转换为关节成形术的速度，记录了5年和10年的生存率，以及BMI对生存的危险比(HR)。
结果：本研究共纳入574例：HW组（n=96），OW组(n=233)和OB组(n=245)，平均BMI分别为23±1.5kg/m2、27.4±1.4kg/m2和34.4±3.8kg/m2。平均随访时间为13.3年（4.8-20.3年）。HW组的平均机械胫股角矫正为：7.1±3°，OW组：6.6±3.5°，OB组：7.1±3.8°，组间无显著性差异(p=n.s.)。临床上,尽管OW组和OB组的术前评分较低，三组术后无差异.HW组总并发症发生率为12.5%,OW组的6.8%，OB组为9.8%。HW组和OW组之间并发症的RR没有显着差异（RR=0.6，95％置信区间[CI]=0.3-1.3）（p=0.2），HW和OB组（RR=0.8；95%CI=0.3-2.2）（p=0.7）。三组之间基于BMI的生存结果没有总体显着差异（p=0.4）。HW组和OW组之间转换为关节成形术的HR为1.4[95％CI=0.6-3.5]（p=0.5），HW组和OB组之间为1.8[95％CI=0.8-4.4]（p=0.2）。
结论：BMI对放射学校正均无显著影响，临床结果，短期至中期随访时MOWHTO的并发症或生存率。没有特定的BMI截止点可以推荐为MOWHTO的禁忌症。
方法：四级，回顾性队列研究。
方法：前瞻性维护的1138例膝关节截骨术单中心数据库，在2002年至2022年之间进行了回顾性审查。接受MOWHTO治疗有症状的单室内侧膝骨关节炎（OA）的成年患者，膝盖内翻畸形，保守管理失败，包括在内。根据国家健康与护理卓越研究所（NICE）的分类，根据BMI将患者分为三组：健康体重（HW）组（BMI为18.5-24.9kg/m2），超重（OW）（BMI为25-29.9kg/m2），和肥胖（OB）组（BMI≥30kg/m2）。术前以及术后2年和5年记录了多个患者报告的结果指标（n=6）。术前、术后进行畸形分析。HW之间并发症的相对风险(RR)，计算OW和OB组。转换为关节成形术的速度，记录了5年和10年的生存率，以及BMI对生存的危险比(HR)。
结果：本研究共纳入574例：HW组（n=96），OW组(n=233)和OB组(n=245)，平均BMI分别为23±1.5kg/m2、27.4±1.4kg/m2和34.4±3.8kg/m2。平均随访时间为13.3年（4.8-20.3年）。HW组的平均机械胫股角矫正为：7.1±3°，OW组：6.6±3.5°，OB组：7.1±3.8°，组间无显著性差异(p=n.s.)。临床上,尽管OW组和OB组的术前评分较低，三组术后无差异.HW组总并发症发生率为12.5%,OW组的6.8%，OB组为9.8%。HW组和OW组之间并发症的RR没有显着差异（RR=0.6，95％置信区间[CI]=0.3-1.3）（p=0.2），HW和OB组（RR=0.8；95%CI=0.3-2.2）（p=0.7）。三组之间基于BMI的生存结果没有总体显着差异（p=0.4）。HW组和OW组之间转换为关节成形术的HR为1.4[95％CI=0.6-3.5]（p=0.5），HW组和OB组之间为1.8[95％CI=0.8-4.4]（p=0.2）。
结论：BMI对放射学校正均无显著影响，临床结果，短期至中期随访时MOWHTO的并发症或生存率。没有特定的BMI截止点可以推荐为MOWHTO的禁忌症。
方法：四级，回顾性队列研究。
