峡部裂椎体椎弓根钉入点三角骨定位法

Triangular bone positioning of spondylolysis vertebral pedicle screws

目的：探寻一种简单、准确、可靠的峡部裂椎体椎弓根入点定位方法。方法研究分为两个阶段：①2008年1月~2012年1月,对60例峡部裂伴椎体滑脱患者应用CT测量峡部裂椎体椎弓根中轴线至三角骨下边的距离及其至三角骨内下角顶点的距离；对其中30例患者行手术治疗,术中在C臂机下找出峡部裂椎体椎弓根标准入点,测量峡部裂椎体椎弓根中轴线至三角骨下边的距离及其至三角骨内下角顶点间的距离。②2012年2月~2014年1月,将60例峡部裂伴腰椎滑脱的患者,分别采用三角骨定位法置钉（A组,n=30）和AO法置钉（B组,n=30）,两组患者术前资料比较差异无统计学意义（P〉0．05）。对比两组手术时间、手术出血量及术后的疼痛评分,手术后应用X线和CT检查验证置钉效果。结果进钉点位于三角骨面内、靠下方,大约在内下角下1/3分界线上下的区域内,距离内下角顶点4~7 mm,距离下边3~6 mm,在进针方向上,入点越靠外侧,钉尾外倾角度越大,入点越靠上方,钉尾头倾角度越大。对比两种方法手术结果,A组明显优于B组（P〈0．05）。结论三角骨内下角及下边无明显增生,骨面清晰明确,面积小,位置恒定。应用该定位方法置钉,操作简单、可靠、创伤小、出血少,可明显提高一次性置钉率及置钉优良率,缩短手术时间。

Objective To search for a simple, accurate and reliable positioning method of positioning spondylolysis vertebra pedicle screw, and to evaluate the effect. Methods Research methods were divided into two stages： ①Frome January 2008 to January 2012, the distance between spondylolysis vertebral pedicle axis with lower boundary of triangular bone and the distance between spondylolysis vertebral pedicle axis with annulus inferior and medial oftrian-gular bones was measured by CT for 60 paitiens. In the same period, the distance between spondylolysis vertebral pedicle axis with lower annulus inferior and medial of triangular bone was measured by C arm X-ray in operations for 30 paitiens. ②From February 2012 to January 2014, patients with spondylolysis and spondylolisthesis of the lumbar spine were divided into two groups（group A,n=30; group B,n=30）. Respectively,this method and AO method were used to locate the point into the vertebral pedicle. Nailing effect was evaluated by X-ray and CT after the opera-tions. Operation time, blood loss and accuracy rate of locate pedicle were recorded;Then a comparison between the AO method and the new method was made. Results The entry point was located in the lower part of the triangular bone surface. It was about on the inferior trisectrix of interior-inferior angle of triangular bone. The distance was 3~6mm between the interior-inferior angle and the entry point. The distance was 4~7mm between the lower boundary and the entry point. About the direction of the needle, when the entry point was on the outside that the camber angle of the nail end was bigger, when the entry point was on the above that the tail angle of the nail end was bigger. It was found that group A was better than group B by comparing the results of the two methods（P〈0. 05）. Conclusions Triangular bone is clear. Its area is small. And it′s position is constant. The new method is simple, reliable, small trauma, less bleeding and less muscle damage. This method significantly increases the rate of one-time nailing and shortens operation time.