胸弯为主的青少年特发性脊柱侧凸后路矫形术后肩部失平衡的危险因素分析

Risk factors of postoperative shoulder imbalance after major thoracic curve correction in patients with adolescent idiopathic scoliosis

目的：观察以胸弯为主的青少年特发性脊柱侧凸（AIS）患者后路矫形术后肩部失平衡的发生情况，探讨其危险因素。方法：回顾性分析96例以胸弯为主的AIS患者的临床资料，Lenke分型为Lenke 1、2、3、4型，均为右胸弯且Cobb角＜80°。男15例，女81例；年龄10～18岁，平均14.5岁。均采用后路椎弓根螺钉系统固定矫形，随访22～68个月，平均42.2个月。根据术后肩部平衡情况，将患者分为肩部平衡组和肩部失平衡组，分析比较两组患者的临床资料和影像学特点。结果：肩部失平衡患者17例，发生率为17.7%。单变量分析和Logistic回归分析的结果发现与术后肩部失平衡相关的3个独立因素为：术前锁骨角（OR=1.873，P=0.018）、术前主胸弯Cobb角（OR=2.222，P=0.028）和术后主胸弯Cobb角（OR=0.483，P=0.039）。其中锁骨角和术前主胸弯Cobb角为危险因素，术前锁骨角的正值越大，主胸弯角度越大，术后肩部失平衡的危险性越大；术后主胸弯Cobb角为保护因素，术后主胸弯残余角度较大时，能相对避免肩部失平衡的发生。结论：术前锁骨角为正性倾斜、主胸弯角度较大和术后主胸弯残余角度过小可能是AIS患者主胸弯矫正后肩部失平衡的独立危险因素。

Objectives： To investigate the prevalence and risk factors of postoperative shoulder imbalance after posterior correction of major thoracic curve in patients with adolescent idiopathic scoliosis. Methods： A retrospective review of 96 consecutive patients undergoing posterior segmental pedicle screw correction and fusion was carried out, the pathogenisis included Lenke 1, 2, 3, 4 types with right thoracic curve of less than 80°. There were 15 males and 81 females with a mean age of 14.5 years（10-18 year）. The average follow-up was 42.2 months（range, 22-68 months）. According to postoperative shoulder height difference, all patients were divided into balance group and imbalance group. Demographics and radiographic data were studied to determine risk factors for postoperative shoulder imbalance. Results： Among the 96 patients, 17 cases（17.7%） presented with postoperative shoulder imbalance. Univariate and multivariate logistic regression analysis between two groups identified clavicle angle（OR=1.873, P=0.018）, preoperative main thoracic Cobb angle（OR=2.222, P=0.028） and postoperative main thoracic Cobb angle （OR=0.483, P=0.039）, as independent factors correlated with postoperative shoulder imbalance. Great clavicle angle and preoperative main thoracic Cobb angle were risk factors, while great postoperative main thoracic Cobb angle was a protective factor for postoperative shoulder imbalance. Conclusions： Positive tilt of clavicle angle, great preoperative main thoracic Cobb angle and small postoperative main thoracic Cobb angle are independent factors for postoperative shoulder imbalance in patients with major thoracic curve undergoing posterior surgery.