股骨复合型带锁髓内钉的设计及临床应用

目的 阐述股骨复合型带锁髓内钉(femoral compound interloeking intramedullary nail,FCIIN)的设计原理,探讨其临床疗效.方法 根据股骨髓腔形态学特点,没计FCIIN的主钉弧度半径为1250 mm,近端斜形交锁角度(钉的颈干角)为135°.主钉近端有三个直径6.5 mm的锁钉孔,使锁钉可以横穿,也可以向左上或下、右上或下45°斜穿.主钉远端有两个直径4.5 mm的锁钉孔和一个相同直径的凹槽.近端锁钉尖部有长30～40 mm自攻松质骨螺纹,螺纹直径由3.5 mm逐渐增大至6.5 mm.远端锁钉有两种:一种是螺纹锁钉,另一种是螺栓锁钉.2000年1月至2004年12月,用FCIIN治疗股骨骨折患者47例,男31例,女16例;年龄18～74岁,平均39.83岁;转子间骨折14例,转子下骨折7例,股骨干骨折18例,髁上骨折8例.其中不扩髓顺行打钉30例.结果 所有患者均获得随访,随访时问21～36个月,平均25.9个月.骨愈合时间6～18个月,平均8.4个月.解剖复位34例,良好复位11例,力线复位2例,复位优良率95.74%.取钉时问12～21个月,平均16.9个月.1例转子间骨折固定失败并骨不愈合患者,采用辅助外固定支架治疗,18个月后骨折愈合.远端锁钉安装失败5例,未做任何处理骨折均愈合.结论 FCIIN 临床应用效果理想,可用于治疗各类股骨骨折.

The design characteristics of a new femoral compound interlocking intramedullary nail and its clinical outcome

Objective The design characteristics and clinical outcome of a femoral compound interlocking intramedullary nail(FCIIN)were investigated.Methods According to morphological characteristics of the femoral medullary canal,a radius of radian of intramedullary nail and a oblique interlocking angle were designed to 1250 mm and 135°.Interlocking holes with three 6.5 mm diameter were located in proximal end of FCIIN.Two locking holes and a recess,which was 4.5 mm in diameter,were located at the distal end of FCIIN.At the tip of the proximl interlocking screws whose root diameter rose from 3.5 mm to 6.5 mm gradually,the self-tapping cancellous screw thread was designed.There were two types of distal interlocking screws.One was fine thread screw and the other was bolt screw.Under the biomechanical destructive test,the proximal interlocking screw device had satisfactory strength and reasonable structure.A total of 47 patients with fractures of femur were assessed in this study.There are 31 males and 16 females,with average age of 39.83 years (range 18-74 years).Among them 14 patients were diagnosed as intertrochanteric fracture,7 cases as subtrochanteric fracture,18 cases as femoral shaft fractures,and 8 cases as snpraeondylar fracture.All patients were treated by FCIIN.Results All patients have been followed up for 21-36 months with an average of 25.9 months.The fracture healing time was 6-18 months with an average of 8.4 months.of all 47 patients,anatomic reduction were achieved in 34 cases,good reduction in 11 cases,and force line reduction in 2 cases.The excellent or good rate was in 95.74%.The removal time of FCIIN was 12 to 21 months (average,16.9 months).One patient with intertrochanteric fracture who had a fixation failur combined with non-union had achieved healing by external fixator in 18 months.Failure to insert distal interlocking screws during procedure oecurred in 5 patients which did not influence the fracture healing.Conclusion The FCIIN is a useful device in the treatment of the varied types of femoral fracture.