Kirsch Jacob M, Nathani Amit, Robbins Christopher B, Gagnier Joel J, Bedi Asheesh, Miller Bruce S
Department of Orthopaedic Surgery, University of Michigan, Ann Arbor, Michigan, USA.
Department of Epidemiology, University of Michigan, Ann Arbor, Michigan, USA.
Orthop J Sports Med. 2017 Apr 18;5(4):2325967117702126. doi: 10.1177/2325967117702126. eCollection 2017 Apr.
Variations in scapular morphology have been associated with the development of atraumatic rotator cuff tears (RCTs). The critical shoulder angle (CSA) accounts for both glenoid inclination and lateral extension of the acromion. The impact of the CSA on outcomes after rotator cuff repair (RCR) has not been investigated previously.
Our hypothesis was that individuals with smaller CSAs will have better patient-reported outcome scores over time compared with those with larger CSAs. Theoretically, a smaller CSA minimizes the biomechanical forces favoring superior translation of the humeral head, which may be advantageous after RCR. This is the first study to examine the relationship between the CSA and clinical outcomes after RCR.
Cohort study; Level of evidence, 2.
Fifty-three patients (mean age, 61 years) with atraumatic full-thickness RCTs who underwent arthroscopic RCR were prospectively evaluated. Demographic data as well as the Western Ontario Rotator Cuff Index (WORC) score, American Shoulder and Elbow Surgeons (ASES) score, and a visual analog scale (VAS) for pain were prospectively collected at various time points up to 24 months postoperatively. Statistical analysis included longitudinal multilevel regression modeling to investigate the association between the CSA and the WORC, ASES, and VAS scores.
The overall clinical outcome, as measured by the WORC, ASES, and VAS, improved significantly ( < .0001). Controlling for demographic and clinical characteristics, a multilevel regression analysis demonstrated that the CSA was not a significant independent predictor for change in WORC ( = .581), ASES ( = .458), or VAS ( = .859) scores at 24 months after arthroscopic RCR. Interobserver and intraobserver reliability for CSA measurements resulted in interclass correlation coefficients of 0.986 and 0.982, respectively ( < .001), indicating excellent agreement.
The CSA did not appear to be a significant predictor of patient-reported outcomes after arthroscopic repair of atraumatic full-thickness RCTs.
肩胛形态的变异与非创伤性肩袖撕裂（RCTs）的发生有关。关键肩角（CSA）兼顾了关节盂倾斜度和肩峰的外侧延伸。CSA对肩袖修复（RCR）后疗效的影响此前尚未得到研究。
我们的假设是，随着时间推移，与CSA较大者相比，CSA较小的个体患者报告的疗效评分会更好。从理论上讲，较小的CSA可将有利于肱骨头向上移位的生物力学力降至最低，这在RCR后可能具有优势。这是第一项研究CSA与RCR后临床疗效之间关系的研究。
队列研究；证据等级，2级。
对53例（平均年龄61岁）接受关节镜下RCR的非创伤性全层RCT患者进行前瞻性评估。前瞻性收集人口统计学数据以及西安大略肩袖指数（WORC）评分、美国肩肘外科医师学会（ASES）评分和疼痛视觉模拟量表（VAS），直至术后24个月的不同时间点。统计分析包括纵向多水平回归建模，以研究CSA与WORC、ASES和VAS评分之间的关联。
以WORC、ASES和VAS衡量的总体临床疗效有显著改善（P < .0001）。在控制人口统计学和临床特征后，多水平回归分析表明，CSA并非关节镜下RCR术后24个月时WORC（P = .581）、ASES（P = .458）或VAS（P = .859）评分变化的显著独立预测因素。CSA测量的观察者间和观察者内可靠性分别产生组内相关系数为0.986和0.982（P < .001），表明一致性极佳。
在非创伤性全层RCT关节镜修复术后，CSA似乎并非患者报告疗效的显著预测因素。
