Lenke 1型青少年特发性脊柱侧凸患者术后双肩失平衡的影像学评估

Radiographic assessment of shoulder balance in Lenke type Ⅰ adolescent idiopathic scoliosis following posterior all pedicle screws instrumentation and fusion

[目的]对行全椎弓根螺钉治疗的Lenke 1型青少年特发性脊柱侧凸患者术后双肩失平衡的影像学危险因素进行分析。[方法]选择长海医院行全椎弓根螺钉治疗的Lenke 1型青少年特发性脊柱侧凸患者80例,随访至少2年。测量T1倾斜(T1 tilt)、锁骨角(clavicle angle,CA)、影像学肩高(radiographic shoulder height,RSH)等影像学参数。根据RSH分级的绝对值术后是否大于术前,将其分为术后平衡组与失平衡组,并对两组患者的影像学参数进行对比分析。[结果]术后双肩失平衡的发生率为22.5%。双肩失平衡组正性T1倾斜、正性锁骨角的比例远高于平衡组(P<0.001)。术前双肩水平的患者术后更易出现双肩失平衡(25.8%vs 83.3%,P<0.001)。25.8%的双肩平衡患者上胸弯Cobb角≥30°,而双肩失平衡患者该比例高达55.6%(P=0.018);50.0%的双肩平衡患者主胸弯与上胸弯的Cobb角差值≥25°,而双肩失平衡患者该比例仅为22.2%(P=0.036)。平衡组30.6%患者随访时主胸弯与上胸弯矫正率的差值≥1.8,失平衡组中该比例达61.1%(P=0.019)。[结论]T1倾斜、锁骨角、术前双肩平衡状态、上胸弯Cobb角、主胸弯与上胸弯的Cobb角差值及主胸弯与上胸弯矫正率的比值是较好的预测Lenke 1型青少年特发性脊柱侧凸患者术后双肩失平衡的影像学参数。

[Objective] This study was designed to analyze the risk factors of postoperative shoulder asymmetry（ PSA） in Lenke type I adolescent idiopathic scoliosis（ AIS） following posterior all pedicle screws instrumentation and fusion by radiography. [Methods] Eighty patients with consecutive AIS and a minimum of 2- year follow- up after treatment with posterior all pedicle screws instrumentation and fusion were evaluated. Radiographic measurements included coronal and sagittal parameters on preoperative,early post- operation,and final follow- up standing long cassette radiographs. Parameters of shoulder balance such as T1 tilt,clavicle angle,and radiographic shoulder height（ RSH） were also measured. PSA was defined as the absolute value of the RSH grade at the final follow- up greater than that of the preoperative RSH grade. [Results] At final follow- up,PSA incidence was 22. 5%（ 18 out of 80 patients）. Radiographic parameters that were statistically significant for PSA were preoperative positive T1 tilt（ P〈0. 001）,preoperative positive clavicle angle（ P〈0. 001）,preoperative shoulder balance（ preoperative RSH grade = 0）（ P〈0. 001）,preoperative proximal thoracic（ PT） Cobb（ PT 30°）（ P = 0. 018）,difference between preoperative main thoracic（ MT） and PT Cobb（ 25°）（ P = 0. 036）,and ratio of MT correction rate to PT at final follow- up（ 1. 8）（ P = 0. 019）. [Conclusion] Preoperative T1 tilt,preoperative clavicle angle,preoperative shoulder balance（ preoperative RSH grade = 0）,preoperative proximal thoracic（ PT） Cobb,difference between preoperative main thoracic（ MT） and PT Cobb,and ratio of MT correction rate to PT at final follow- up are radiographic predictors for PSA.