Wenning Markus, Sofack Ghislain N, Zöller Daniela, Mauch Marlene, Heitner Albrecht H, Paul Jochen, Zahn Peter, Ritzmann Ramona
Department of Orthopaedic and Trauma Surgery, University Medical Center, Faculty of Medicine, University of Freiburg, Germany.
Orthopaedic Surgery, BDH Klinik Waldkirch, Waldkirch, Germany.
Orthop J Sports Med. 2024 Sep 4;12(9):23259671241264845. doi: 10.1177/23259671241264845. eCollection 2024 Sep.
The limb symmetry index (LSI) is a metric of strength restoration. It is key to successfully return to sports after anterior cruciate ligament (ACL) reconstruction. The threshold for return to sports is generally considered an LSI of ≥85%.
To develop a statistical model for predicting the recovery of knee extension and flexion strength (with LSI ≥85%) at 6 months after ACL reconstruction.
Case-control study; Level of evidence: 3.
Patients who underwent arthroscopic ACL reconstruction between November 2015 and December 2020 were included. The patients were classified into 2 groups: "pass" if the LSI at 6 months postoperatively was ≥85% and "fail" if the LSI was <85%. Factors in 25 categories with 74 levels, including patient characteristics, periarticular procedures, intra-articular lesions and treatment, and perioperative management, were collected. A multivariable logistic regression combined with backward variable elimination was used to determine the predictive parameters for recovery of knee extension and flexion strength.
A total of 948 patients were included. Graft site, preoperative isokinetic strength, treatment of meniscal injury, and injured side (left vs right) were identified as general predictors for both knee extension and flexion strength. For knee strength, age at injury and partial weightbearing duration were identified as additional predictors. For knee strength, type of meniscal injury, surgeon volume, cartilage procedures, and periarticular procedures were identified as additional predictors. The Nagelkerke of the final model was 0.178, and the -statistic was 0.716 (95% CI, 0.676-0.754). The Hosmer-Lemeshow test indicated good calibration ( = .879).
Several factors including preoperative isokinetic strength, treatment of meniscal injuries, left vs. right side and graft site were found to predict recovery of ≥85% LSI in knee extension and flexion strength. Despite the numerous factors that were analyzed, the predictive power was moderate (c-statistic = 0.716), indicating there were other nonincluded factors that significantly influence strength performance at 6 months postoperatively.
肢体对称指数（LSI）是力量恢复的一项指标。它是前交叉韧带（ACL）重建后成功重返运动的关键。重返运动的阈值通常被认为是LSI≥85%。
建立一个统计模型，用于预测ACL重建术后6个月时膝关节伸展和屈曲力量的恢复情况（LSI≥85%）。
病例对照研究；证据等级：3级。
纳入2015年11月至2020年12月期间接受关节镜下ACL重建的患者。将患者分为两组：术后6个月时LSI≥85%为“通过”组，LSI<85%为“未通过”组。收集了25个类别74个水平因素，包括患者特征、关节周围手术、关节内病变及治疗以及围手术期管理。采用多变量逻辑回归结合向后变量消除法来确定膝关节伸展和屈曲力量恢复的预测参数。
共纳入948例患者。移植物部位、术前等速肌力、半月板损伤的治疗以及受伤侧（左或右）被确定为膝关节伸展和屈曲力量的一般预测因素。对于膝关节伸展力量，受伤时年龄和部分负重持续时间被确定为额外的预测因素。对于膝关节屈曲力量，半月板损伤类型、外科医生手术量、软骨手术以及关节周围手术被确定为额外的预测因素。最终模型的Nagelkerke R²为0.178，c统计量为0.716（95%CI，0.676 - 0.754）。Hosmer-Lemeshow检验表明校准良好（P = 0.879）。
发现包括术前等速肌力、半月板损伤的治疗、左右侧以及移植物部位等多个因素可预测膝关节伸展和屈曲力量恢复至LSI≥85%。尽管分析了众多因素，但其预测能力为中等（c统计量 = 0.716），表明存在其他未纳入的因素对术后6个月的力量表现有显著影响。
