特发性胸椎右侧凸患者经胸前路手术时不缝合胸膜对主动脉偏移的影响

Effect of non-sutured pleura after anterior approach on the position of the aorta in patients with right thoracic idiopathic scoliosis

目的：探讨特发性胸椎右侧凸畸形患者行经胸前路手术时不缝合胸膜对主动脉偏移的影响。方法：20例青少年特发性胸椎右侧凸畸形行经胸前路手术的患者分为两组，A组13例，均为女性患者，平均14.0岁，胸弯Cobb角平均45.1°，术中均缝合胸膜。B组7例，均为女性，平均14.8岁，胸弯Cobb角平均64.6°，术中不缝合胸膜。统计两组患者术后胸腔引流量及胸腔引流管拔管时间。两组患者手术前后均行胸椎T5-T12节段CT扫描.在每个节段测量右侧肋骨头至主动脉后壁的切线与双侧肋骨头连线的夹角（α）、椎管前缘中点与主动脉中心连线和双侧肋骨头连线的夹角（β）、主动脉与椎体间距离（α）以及与左侧肋骨头前缘的垂直距离（b），并进行比较。结果：A组患者术后置钉安全角（α）、主动脉相对椎管前缘旋转角（β）较术前增大，在T8、1、9差异有显著性（P〈0.05）；术后主动脉与椎体间距离（a）减小，主动脉后壁与右侧肋骨头间距离（b）增大，和术前相比在T9有显著性差异；术后平均胸腔引流量220ml，平均拔管时间6d。B组患者手术后α、β角减小，a值增大、b值减小，所有术后指标的改变在多数节段有显著性差异，术后平均胸腔引流量350ml，平均拔管时间8d。结论：特发性胸椎右侧凸患者经胸前路矫形术时缝合胸膜后主动脉相对椎体向前方偏移并靠近椎体，而不缝合胸膜者主动脉相对椎体向后方偏移并远离椎体，不缝合胸膜可给予前路或后路置钉更大的安全空间。

Objective：To quantify the change of spatial relationship between the vertebral body and the thoracic aorta in idiopathic thoracic scoliosis with and without closing the pleura during anterior approach. Method：20 consecutive patients undergoing thoracotomic anterior spinal fusion were divided into 2 groups. Group A included 13 females with plerura closed when operating,with an average age of 14.0 years and average main thoracic Cobb angle of 45.1°.Group B included 7 females with pleura open when operating,with an average age of 14.8 years and average main thoracic Cobb angle of 64.6°.The amount of pleural drainage and extubation time between group A and B were compared.CT scanning form T5 to T12 was performed for both groups before and after operation and the following parameters were analyzed,including the angle for safety screw placement composed of the line linking the left and right rib heads and the line from the fight rib head to the posterior wall of the aorta （α）,the angle composed of the line linking the left and right rib heads and the line from anterior midpoint of the vertebral canal and to the midpoint of the aorta（β）,the distance from the aorta to the closest point of the vertebral body cortex（a） and distance from the posterior wall of the aorta to the anterior edge of the left rib head （b）.Result：In group A,the α angle and β angle increased after operation,and significant difference was found at T8 and T9 levels （P〈0.05）.The a value decreased and b value increased after curve correction and reached significant difference at Tg（P〈0.05）.However,in group B,both the α angle and β angle decreased.The a value increased and b value decreased after correction. The average amount of post-operative pleural drainage was 220ml in group A,and 350ml in B.The average extubation time of pleural cavity was 6d and 8d respective]y.ConclusionzThe aorta can anteromedialy relatively to vertebral body when the anterior approach with pleura closed,however,the can move posterolaterally relatively to vertebral body with pleura open.There seemed to be more safe without closing pleura for anterior and posterior instrumentation.