股骨干骨折闭合复位髓内钉固定术中大转子倾斜指数的应用

Application of the greater trochanter tilting index in close reduction and intramedullary nail fixation of a femoral shaft fracture

目的探讨股骨干骨折闭合复位髓内钉固定术中利用大转子倾斜指数指导旋转力线恢复的有效性。方法2011年1月至2012年1月采用闭合复位髓内钉固定治疗24例股骨干骨折患者，男20例，女4例；年龄17～61岁，平均36.5岁；均为单侧闭合性骨折。骨折AO分型：32A2型11例，32B2型8例，32C2型5例。闭合复位髓内钉固定术中根据大转子倾斜指数计算出股骨近端的旋转角度及状态；若股骨近折端外旋≥15°，而采用Schanz 钉内旋技术纠正外旋畸形，然后插入髓内钉并锁定；若股骨近折端外旋〈15°，而先插入髓内钉，锁定近端，然后旋转股骨远端，纠正旋转畸形，锁定远端。术后应用CT测量并比较患者患肢与健肢的股骨颈前倾角，判断旋转复位情况。结果24例患者术后患肢与健肢股骨颈前倾角平均分别为15.36°±7.91°、14.54°±7.44°，二者比较差异无统计学意义（t=0.958,P=0.348）。患肢与健肢股骨颈前倾角差值平均为3.58°±2.26°。所有患者旋转畸形均〈9°，其中股骨远折端内旋畸形15例，外旋畸形8例，无旋畸形1例。24例患者术后获8～20个月（平均13个月）随。骨折均获愈合，愈合时间3～7个月，平均5.1个月。无骨不连、膝关节僵硬等并发症发生。结论应用大转子倾斜指数指导股骨干骨折闭合复位髓内钉固定术，能准确判断股骨近端的旋转状态，有助于纠正旋转移位，降低术后旋转对位不良的发生率。

Objective To assess the usage of greater trochanter tilting indes in the close reduction and intramedullary nail fixation of femoral shaft fracture for correction of rotational deformity. Methods From January 2011 to January 2012 we treated 24 patients with one-sided and closed femoral shaft fracture. They were 20 men and 4 women, aged from 17 to 61 years （average, 36.4 years）. By AO classification 11 cases of 32A2, 8 of 32B2 and 5 of 32C2. After the anteroposterior radiograph of the proximal femur was taken, its rotational angle was calculated according to the greater trochanter tilting indes. When the external rotation angle of the proximal femur was≥15°, the Schanz pin skill was used to rectify the extorsion befor inserting the main intramedullary nail; when the angle was 〈15°, the main intramedullary nail was inserted and the proximal locking screws wrer locked befor the rotational deformity was corrected. The anteversion angles of both healthy and affected sides were locked before the rotational deformity was corrected. The anteversion angles of both healthy and affected sides were locked before the rotational deformity was corrected. The anteversion angles of both healthy and affected sides were measured and compared to judge the rotation reduction quality using CT scans . Results In the 24 patients, the anteversion angle was 15.36°±7.91°at the affected side and 14.54°±7.44° at the healthy side, showing no statistically significant difference（t=0.958,P=0.348）. The mean value of D-values between the affected and healthy sides （deformity degrees ）was 3.58°±2.26° . The deformity degrees of all patients averaged less than 9°.Fifteen cases had internally rotational deformity at the distal fracture end , 8 externally rotational deformity and one no deformity.The 24 patients were followed up for 8 to 20 months （average, 13 months）. All fractures obtained union after and average of 5.1 months （from 3 to 7 months ）. No complications like bone nonunion or knee stiffness were found. Conclusion The greater trochanter tilt index can be used as an aid in close reduction and intramedullary nail fixation of femoral shaft fracture because it can help judge the rotational state of the proximal femurs so as to correct the deformity and reduce the incidence of malalignment after operation.