经椎弓根椎体截骨术治疗强直性脊柱炎后凸畸形患者术后肺功能的改变

Pulmonary function improvement in patients with ankylosing spondylitis kyphosis following pedicle subtraction osteotomy

目的：评估强直性脊柱炎（ankylosing spondylitis,AS）后凸畸形经椎弓根椎体截骨（pedicle subtraction osteotomy,PSO）术前和术后患者肺功能的变化,并探讨影响术后肺功能改变的相关因素。方法 ：收集2009年6月~2011年6月收治的32例AS后凸畸形行PSO脊柱矫形术患者的资料。男性27例,女性5例;年龄36.4±7.8岁（22~52岁）。随访时间为2年,随访的内容包括：肺功能检查,静息状态下憋气时间（breath-holding time,BHT）,自然站立位脊柱全长X线片上测量后凸Cobb角（T1~S1）。比较术后及术后2年随访时肺功能较术前是否有变化,并分析肺功能变化与性别、年龄、病程和脊柱矢状面参数之间的关系。结果：29例（男性25例,女性4例）患者完成了随访,失访率为9.3%。手术前BHT为32.5±10.1s,2年随访时增加至43.1±8.6s。术前肺功能检查结果：2例正常,17例轻度限制性通气功能障碍,9例中度限制性通气功能障碍,1例重度限制性通气功能障碍,无阻塞性通气功能障碍及混合性通气功能障碍;2年随访时肺功能检查结果：19例正常,10例轻度限制性通气功能障碍。肺活量预测百分比（Pred VC%）术前为68.4%±9.5%,2年随访时为79.4%±6.1%;用力肺活量预测百分比值（Pred FVC%）术前为75.5%±6.4%,2年随访时为81.0%±6.9%。后凸Cobb角术前为63.0°±20.3°,术后为15.3°±10.3°,术后2年随访时为17.1°±10.9°。且Pred VC%和Pred FVC%的改善与AS后凸Cobb角的矫正成正相关性（r=0.6328和0.8612,P〈0.01）。结论：AS后凸畸形PSO术后2年肺功能较术前改善明显,且肺功能的改善与T1~S1后凸Cobb角的矫正呈正相关性。

Objectives： To observe postoperative change in pulmonary function in patients with ankylosing spondylitis （AS） kyphosis after pedicle subtraction osteotomy （PSO）, and investigate the related factors of pulmonary function changes after operation. Methods： From June 2009 to June 2011, a total of 32（27 males and 5 females） patients with AS kyphosis were eligibiy involved. 29（25 males and 4 females） patients with a mean age of 36,4±7.8 years （range, 22-52 years） completed the follow-up and 3 （2 males and I female） patients lost. Pulmonary function tests, breath-holding time and full-length spine X-ray films in natural standing position were followed postoperatively. The study explored whether there was a change in lung function postoperatively, the relationship of the possible existence of lung funetion changes with gender, age, course of the disease and the spinal sagittal parameters was investigated. Results： Cobb T1-S1 significantly decreased from 63.0°±20.3° preoperatively to 15.3°±10.3° postoperatively and 17.1°±10.9° at 2-year follow-up. The breath-holding time（BHT） before surgery was 32.5±10.1s, while the postoperative BHT increased to 43.1± 8.6s （P〈0.05）. Two AS patients had normal pulmonary function test before operation, while there were 19 patients at 2-year follow-up. The clinical improvement rate was 85.2%（23/27）. The percentage predicted vital capaeity（PredVC%） increased from （68.4±9.5）% to （79.4°±6.1）% at 2-year follow-up（P〈0.05）. The percentage predicted forced vital capacity（PredFVC%） before PSO was （75.5±6.4）% and （81.0°±6.9）% at 2-year follow-up （P〈0.05）. The improved PredVC% and PredFVC% had a positive correlation with the correction of Cobb T1- S1（r=0.6328 and 0.8612, P〈0.01, respectively）. Conclusions： The postoperative pulmonary function including pulmonary volume and ventilatory function in AS patients with kyphosis is significantly improved at 2-year follow-up. And the improved puhnonary function has a positive correlation with the kyphosis correction.