Erickson Brandon J, Werner Brian C, Griffin Justin W, Gobezie Reuben, Lederman Evan, Sears Benjamin W, Bents Easton, Denard Patrick J
Rothman Orthopaedic Institute, New York, NY, USA.
University of Virginia, Charlottesville, VA, USA.
J Shoulder Elbow Surg. 2022 May;31(5):963-970. doi: 10.1016/j.jse.2021.10.010. Epub 2021 Oct 29.
Although reverse total shoulder arthroplasty (RTSA) has excellent reported outcomes and satisfaction, patients often have postoperative limitations in range of motion (ROM), specifically internal rotation. Increased lateralization is thought to improve ROM following RTSA. The purpose of this study was to evaluate the association between radiographic measurements of lateralization and postoperative ROM and clinical outcome scores following RTSA. The authors hypothesized that increased radiographic lateralization would be associated with improved postoperative ROM, specifically internal rotation, but have no significant association with clinical outcome scores.
Patients who underwent RTSA with a 135° neck-shaft angle prosthesis and minimum 2-year clinical and radiographic follow-up were included and retrospectively reviewed. Postoperative radiographs were evaluated for several lateralization measurements including the lateralization shoulder angle (LSA), distance from the lateral border of the acromion to the lateral portion of the glenosphere, distance from the glenoid to the most lateral aspect of the greater tuberosity, and the distance from the lateral aspect of the acromion to the most lateral aspect of the greater tuberosity. Linear regression analyses were used to evaluate the independent association of each radiographic measurement of lateralization on forward flexion, external rotation, internal rotation, and the American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES) index score at 2 years postoperation. Receiver operating characteristic (ROC) curves were constructed to identify significant thresholds of each radiographic lateralization measurement.
A total of 203 patients were included. For internal rotation, a greater LSA (P = .007), shorter acromion to glenosphere distance (meaning more glenoid lateralization) (P = .005), and a greater acromion to greater tuberosity distance (with the tuberosity more lateral to the acromion) (P = .021) were associated with improved internal rotation. Overall, ROC analysis demonstrated very little significant data, the most notable of which was the LSA, which had a significant cutoff of 82° (sensitivity 57%, specificity 68%, P = .012).
Of the numerous radiographic measures of lateralization after RTSA, the LSA is the most significantly associated with outcomes, including improved internal rotation and a decrease in forward flexion and ASES score. The clinical significance of these statistically significant findings requires further study, as the observed associations were for very small changes that may not represent clinical significance.
尽管全肩关节置换术（RTSA）的术后效果和患者满意度都很好，但患者术后常存在活动范围（ROM）受限的情况，尤其是内旋。增加假体的外移被认为可改善RTSA术后的活动范围。本研究旨在评估假体外移的影像学测量值与RTSA术后活动范围及临床结局评分之间的关联。作者假设影像学上更大的外移与术后更好的活动范围相关，尤其是内旋，但与临床结局评分无显著关联。
纳入接受135°颈干角假体RTSA且有至少2年临床及影像学随访资料的患者，并进行回顾性分析。评估术后X线片的多项外移测量指标，包括外移肩角（LSA）、肩峰外侧缘至关节盂球部外侧的距离、关节盂至大结节最外侧的距离以及肩峰外侧至大结节最外侧的距离。采用线性回归分析评估每项外移影像学测量指标与术后2年的前屈、外旋、内旋以及美国肩肘外科医师协会标准化肩关节评估表（ASES）指数评分之间的独立关联。绘制受试者工作特征（ROC）曲线以确定每项外移影像学测量指标的显著阈值。
共纳入203例患者。对于内旋，更大的LSA（P = .007）、肩峰至关节盂球部距离较短（即关节盂外移更多）（P = .005）以及肩峰至大结节距离更大（大结节位于肩峰更外侧）（P = .021）与更好的内旋相关。总体而言，ROC分析显示显著数据很少，其中最显著的是LSA，其显著临界值为82°（敏感性57%，特异性68%，P = .012）。
在RTSA术后众多外移的影像学测量指标中，LSA与结局的相关性最为显著，包括内旋改善以及前屈和ASES评分降低。这些具有统计学意义的发现的临床意义需要进一步研究，因为观察到的关联是非常小的变化，可能不具有临床意义。
