弹性进钉法制备胸椎椎弓根钉道在胸椎侧凸中的应用

目的：探讨弹性进钉法制备胸椎椎弓根钉道植入螺钉的方法，总结临床应用效果。方法：咬除进钉点骨皮质，以据术前测量的深度和旋转的程度，分别先后用1．5mm、2．5mm克氏针沿椎弓根方向钻孔。达到测定的深度停止进针，球形探子探查无误后改用导锥顺着制造的钉道小心缓慢进入，深度一致后，再次用球形探子探查，植入螺钉。结果：胸椎椎弓根螺钉一次性植入成功为96．2％，其中18枚术中发现，偏内侧5枚，偏下方3枚，偏上方4枚，偏外方6枚，其中偏外侧的4枚螺钉把持力坚强外，另2枚重新阅读影像资料，用2．5mm克氏针，改变锥入方向，5枚偏内侧的螺钉中3枚同时切除了该同侧的椎板，行术中探测，钉道均成功得以置备。钉道制备后增加螺钉直径0．5mm，进行补救。其余的14枚螺钉都是术后通过CT或者X线片发现的，且均偏外侧。1例术中脑脊液漏者骨蜡封闭后术后未发生脑脊液漏，本组无脊髓损伤。平均术后身高增加4．6cm，术后冠状面Cobb角平均21°，平均矫正率73％；矢状面Cobb角平均230°旋转畸形矫正Ⅰ～Ⅱ度。平均随访3．5年。最终随访矫正度丢失率为1．8％。迟发性感染1例，螺钉断裂4例，1例螺钉向椎弓根外侧偏移加重。躯干平衡良好、无平背。结论：弹性进钉法制备胸椎椎弓根钉道准确率高、并发症少。

Elastic Screw Insertion Technique for Preparing the Canal of Pedicle Screws in Thoracic Scoliosis

Objective： To observe the result of elastic screw insertion technique for preparing the canal of pedicle screws in thoracic seoliosis. Methods： Cortical bone was removed at the screw insertion point with rongeur for-ceps. Then according to the depth and rotation degree that measured preoperatively, drilling along the direction of pediele of vertebral arch using 1.5ram and 2.Smm Kirschner wire respectively. If the resistance was increasing and Kirschner wire was bending, it needs to adjust the direction. Stop to drill when reach the depth, checking the hole with globular specillum to make sure that there is no mistake, then insert strike awl slowly till the same depth, checking the hole with specillum again before implanting the screws. Results： 96.2% was successful inserted by one time, there were 18 screws with wrong direction, medial in 5, below in 3, superior in 4 and lateral in 6. 4 of 6 lateral screws were very firm, other 2 screws were successful inserted again with 2.Smm Kirsehner wire through adjusting the direction. 3 of 5 medial screws, homolateral vertebral plate were removed at the same time, exploration was carried out during the operation and the path was successfully made, then screws were inserted again by increasing 0.5mm in diameter. 14 screws were found by postoperative CT or X-ray and show lateral position. I case hand leakage of cerebrospinal fluid intro-operatively, blocked with bone wax and disappeared after surgery. There were no patients with spinal cord injury, leakage of cerebrospinal fluid, or infection of incisional wound. Razor back deformity was obvious improved and body height was increased by 4.6mm after surgery. The Cobb angle in coronal plane was 21°after surgery and correction rate was 73%, The Cobb angle in sagittal plane was 23°. Rotation deformity was corrected for I to Ⅱdegrees. Follow-up duration was mean 3.5 years. The correc- tion was lost 1.8% in final follow-up visit. 1 case with tardive infection. 4 screws were broken. 1 lateral screw was worse. Trunk balanc