Amini Michael H, Patel Midhat, Stone Geoffrey P, Roberson Troy A, Brolin Tyler J, Sykes Joshua B
CORE Institute, Mesa, Arizona, U.S.A..
Department of Orthopaedic Surgery, University of Arizona College of Medicine, Phoenix, Arizona, U.S.A.
Arthroscopy. 2023 Feb;39(2):225-231. doi: 10.1016/j.arthro.2022.08.042. Epub 2022 Oct 5.
To determine whether the critical shoulder angle (CSA) in acute, traumatic rotator cuff tears (RCTs) is consistent with the previously described CSA in chronic degenerative RCTs.
We performed a multicenter retrospective analysis of 134 patients presenting to 5 surgeons fellowship trained in shoulder and elbow or sports. Preoperative imaging was used to measure the CSA and tear characteristics. Patients were included if they had acute, traumatic full-thickness RCTs documented on advanced imaging and had preoperative Grashey radiographs. Patients were excluded if they had any history of shoulder pain, injury, surgery, or treatment prior to the current episode; were overhead athletes; or had fatty infiltration greater than Goutallier grade 1 on imaging.
The mean CSA was 33.5° (standard deviation, 4.1°), and 60% of tears had a CSA of less than 35°, much below the mean of 38.0° and the threshold of greater than 35° in degenerative RCTs. The mean age was 58 years, and 70% of patients were men. Overall, 60% of tears involved the subscapularis, 49% of tears occurred in patients aged 60 years or older, and 18% of patients sustained a dislocation. Older age (β = 0.316, P = .003) and male sex (β = 5.532, P = .025) were predictive of tear size, and older age (β = 0.229, P = .011) and biceps avulsion (β = 8.822, P = .012) were predictive of tear retraction.
Acute, traumatic RCTs have CSAs that are 5° smaller than those of degenerative tears, and the majority (60%) have CSAs that are below the threshold consistent with degenerative RCTs. The majority of traumatic tears (60%) involve the subscapularis.
The study findings suggest that a traumatic tear is not simply the acute failure of a degenerative tendon and that it represents a distinct pathologic entity. These findings support current practice of treating traumatic RCTs differently than degenerative RCTs.
确定急性创伤性肩袖撕裂（RCT）中的临界肩角（CSA）是否与先前描述的慢性退行性RCT中的CSA一致。
我们对134例患者进行了多中心回顾性分析，这些患者由5位接受过肩肘或运动专科培训的外科医生诊治。术前影像学用于测量CSA和撕裂特征。纳入标准为在高级影像学检查中记录有急性创伤性全层RCT且有术前Grashey位X线片的患者。排除标准为在本次发作之前有任何肩部疼痛、损伤、手术或治疗史的患者；从事过头运动的运动员；或影像学上脂肪浸润大于Goutallier 1级的患者。
平均CSA为33.5°（标准差4.1°），60%的撕裂CSA小于35°，远低于退行性RCT中38.0°的平均值和大于35°的阈值。平均年龄为58岁，70%的患者为男性。总体而言，60%的撕裂累及肩胛下肌，49%的撕裂发生在60岁及以上的患者中，18%的患者发生脱位。年龄较大（β = 0.316，P = 0.003）和男性（β = 5.532，P = 0.025）是撕裂大小的预测因素，年龄较大（β = 0.229，P = 0.011）和肱二头肌撕脱（β = 8.822，P = 0.012）是撕裂回缩的预测因素。
急性创伤性RCT的CSA比退行性撕裂小5°，大多数（60%）的CSA低于与退行性RCT一致的阈值。大多数创伤性撕裂（60%）累及肩胛下肌。
研究结果表明，创伤性撕裂并非简单地是退行性肌腱的急性失效，而是代表一种独特的病理实体。这些发现支持目前对创伤性RCT与退行性RCT采用不同治疗方法的做法。
