经椎弓根截骨术治疗强直性脊柱炎继发颈胸段后凸畸形

Pedicle subtraction osteotomy for cervicothoracic kyphosis secondary to ankylosing spondylitis

目的评估后路经椎弓根截骨术（PSO）治疗强直性脊柱炎（AS）继发颈胸段后凸畸形的临床疗效。方法2009年1月—2015年3月,本院采用PSO治疗AS继发颈胸段后凸畸形患者7例。患者翻身至手术床之前,先放置石膏床于患者腹侧,并在患者颈胸段与石膏床的空隙处填充数个长方形棉垫。术中C6~T1后方截骨及经C7椎弓根椎体截骨完成后,由台下助手缓慢逐个抽取垫于患者和石膏床之间的长方形棉垫。待棉垫抽取完毕后,患者颈胸段的曲度在重力的作用下恢复至近似直线。然后采用体内弯棒技术进一步增加颈胸段前凸曲度。记录手术时间及术中出血量,用颈胸段（C2~T1）后凸Cobb角、颏眉角（CBVA）、C2~T1矢状面偏移距离（SVA）、疼痛视觉模拟量表（VAS）和健康调查量表（SF-36）评估临床疗效。结果 7例患者平均手术时间260 min,术中平均出血量1 571 m L,平均随访24.4个月,术前C2~T1 Cobb角平均为26.2°,末次随访时为-5.4°。术前CVBA平均为43.1°,术后改善至-0.9°。术前C2~T1 SVA平均为6.7 cm,术后改善至3.0 cm。末次随访时,患者的VAS评分由术前的85.0分改善至17.1分;SF-36躯体机能评分（PCS）由术前的20.7分改善至79.3分;SF-36精神机能评分（MCS）由术前的12.8分改善至81.6分。结论 PSO治疗AS继发颈胸段后凸畸形可以有效地恢复颈胸段的矢状位平衡,较好地改善患者前方视野受限、颏-胸畸形等症状,采用术中体内原位弯棒技术安全可靠。

Objective To evaluate the clinical efficacy of pedicle subtraction osteotomy（PSO） for cervicothoracic kyphosis secondary to ankylosing spondylitis（AS）. Methods From January 2009 to March 2015,a total of 7 AS patients who underwent PSO for the correction of cervicothoracic kyphosis were included. Before turning over to the surgical table,a plaster bed was placed to the abdomen of the patient,with the space between plaster bed and patient being filled with several rectangular cotton cushions. After posterior osteotomy,these rectangular cotton cushions were removed gently and singly,allowing the kyphotic curve of cervicothoracic spine slowly to become straight under the action of gravity. And then in vivo rod bending was performed for a better lordotic alignment. The operative time,blood loss,kyphotic Cobb＇s angle（C2-T1）,C2-T1 sagittal vertical axis（SVA）,chin brow vertical angle（CBVA）,visual analog scale（VAS） score and 36-item short form health survey（SF-36） score were all recorded. Results The mean follow-up period was 24.4 months. The mean operative time was 260 min,and the mean blood loss was 1 571 m L. The C2-T1 Cobb＇s angle was improved from preoperative 26.2o to-5.4o at the final follow-up,CVBA from preoperative 43.1o to postoperative-0.9o,and C2-T1 SVA from preoperative 6.7 cm to postoperative 3.0 cm. At the final follow-up,the VAS score was improved from preoperative 85.0 to 17.1,SF-36 physical component score（PCS） from preoperative 20.7 to 79.3 and SF-36 mental component score（MCS） from preoperative 12.8 to 81.6. Conclusion PSO in treatment of cervicothoracic kyphosis secondary to AS can effectively restore the cervical and thoracic sagittal balance and satisfactorily improve symptoms of limited field of view,and chin and chest deformity. The use of in vivo rod bending technology is safe and reliable.