InterTan固定股骨粗隆间骨折拉力钉与骨折线夹角及其与骨折复位的关系

The Angle between the Pulling Nail and Fracture Line in Intertrochanteric Fracture Fixation with InterTan and Its Relationship with the Reduction

目的探讨InterTan内固定治疗股骨粗隆间骨折时拉力钉与骨折线的夹角及其与骨折复位之间的关系,为临床治疗提供理论依据。方法 2009年9月～2011年9月我院采用InterTan内固定术治疗股骨粗隆间骨折患者102例。依照AO分型,选取31-A1.3到A2.3患者共90例,术后3 d拍摄患髋正位片,使用IPP 6.0软件测量拉力钉长轴与主骨折线夹角(A),设预加压长度为D,设实际位移距离为S,相对位移距离为d,代入三角函数进行计算并分析其与骨折复位的关系。结果本组中A角90°以上11例(90.2°～108.8°),80°～90°20例,70°～80°34例,60°～70°17例,60°以下8例(59.1°～46.1°)。12.2%呈钝角,87.8%呈锐角。按预加压长度计算,A角为钝角时:d=Cos(180-A)×D;S=Sin(180-A)×D,d方向向上。A角为锐角时:d=CosA×D;S=SinA×D,d方向向下。结论当拉力钉与骨折线夹角为钝角或锐角时,骨折近端在加压时相对于远端有上移或下移的趋势,提示在复位时应根据该夹角预先留置控制量,从而改善加压后骨折断端相对位置。

Abstract： Objective To discuss the relationship among the pulling force nail, the angle of the fracture line and the fracture reduction after internal fixation with InterTan intramedullary nail to treat femoral intertro- chanteric fracture, and to provide theoretical basis for clinical treatment of such fracture. Methods A total of 102 patients with femoral intertrochanteric fracture were treated with InterTan intramedullary nail fixation in Luhe hospital between September 2009 and September 2011. According to AO classification, 90 patients with 31-A1.3 to A2.3 were selected into the retrospective study. Taken the hip X-ray in the third day of post operation, IPP 6. 0 software was used to measure the pull nail long axis and the main fracture line （Angle A）. After set D for pres- surized length, S for the actual displacement distance, and d for relative displacement distance, and these were taken into the trigonometric functions to calculate and analyze these relationships with the fracture. Results According to the angle of A： there were 11 cases with above 90~ （90.2~ to 108.8~ ） , 20 cases with 80~ to 90~, 34 cases with 70° to 80° , 17 cases of 60° to 70°, 8 cases with 60° below（59.1° to 46.1°）. In addition, 12.2% presented the obtuse angle and 87.8% with sharply. According to the calculation using pre-compression length, if the angle of A is obtuse：d = Cos （180 -A） ×D; S = Sin（ 180 -A）× D, d expressed upwards; if the angle of A is acute ： d = Cos A x D ; S = Sin A x D, d expressed downwards. Conclusions When the angle between the pull nails and the fracture line is obtuse or acute, relative to the part of distal fracture, proximal fractures in the pressure has a tendency to move up or down. These results presented that according to the angle, we should firstly retain the control of quantity, so as to improve the relative position of fracture end after the pressure.