Orthopedics Department, Santa Casa School of Medicine and Hospitals of São Paulo, São Paulo, Brazil.
J Shoulder Elbow Surg. 2011 Oct;20(7):1082-6. doi: 10.1016/j.jse.2011.04.028. Epub 2011 Aug 4.
We compared the acromion index, a lateral tilt of the acromion described by Nyffeler et al as a possible cause of rotator cuff tears (RCTs), in 2 different populations: Brazilian and Japanese.
Patients with full-thickness RCTs diagnosed by magnetic resonance imaging and corroborated by intraoperative findings were included in this study. Controls were patients with shoulder radiographs that indicated instability or adhesive capsulitis. The studied population was subdivided into 2 major racial groups: Brazilian and Japanese. We compared 83 Brazilian adults (mean age, 54 years) with RCTs with 28 individuals with intact rotator cuffs matched by sex, age, and race. Similarly, 112 Japanese individuals (mean age, 59 years) with RCTs were compared with 56 controls. The radiographic images were digitally scanned (HP DeskJet F4180; Hewlett-Packard, Palo Alto, CA, USA) and analyzed.
The mean acromion index of the Brazilian patients with RCTs was 0.72; 0.68 was the result for the Japanese patients. When patients with RCTs were compared with those with intact rotator cuffs, a statistically significant difference was found in the Brazilian population (P = .001) but not in the Japanese population (P = .18). Therefore, Brazilian subjects with RCTs were found to have a greater lateral extension of the acromion than those with intact rotator cuffs. Such a difference, however, was not observed in the Japanese population.
The acromion index can be used as a predictive factor for RCTs in the Brazilian population but not in the Japanese population.
我们比较了 Nyffeler 等人描述的可能导致肩袖撕裂（RCTs）的肩峰指数，即肩峰的外侧倾斜度，在两个不同人群中：巴西人和日本人。
本研究纳入了经磁共振成像诊断为全层 RCTs 且术中发现证实的患者。对照组为肩 X 线片提示不稳定或粘连性关节囊炎的患者。研究人群分为两个主要种族群体：巴西人和日本人。我们比较了 83 名巴西成年人（平均年龄 54 岁）与 RCTs，他们与性别、年龄和种族匹配的 28 名肩袖完整的个体相匹配。同样，112 名日本患者（平均年龄 59 岁）与 56 名对照组进行了比较。放射影像被数字化扫描（HP DeskJet F4180；Hewlett-Packard，Palo Alto，CA，USA）并进行分析。
巴西 RCTs 患者的平均肩峰指数为 0.72；日本患者的结果为 0.68。与肩袖完整的患者相比，巴西 RCTs 患者的肩峰指数存在统计学显著差异（P =.001），但在日本患者中无差异（P =.18）。因此，与肩袖完整的患者相比，巴西 RCTs 患者的肩峰外侧延伸更大。然而，在日本人群中未观察到这种差异。
肩峰指数可作为巴西人群 RCTs 的预测因子，但不能作为日本人群的预测因子。
