肱骨干投弹骨折的分型及意义

Classification of throwing fracture of the humeral shaft and its significance

目的 探讨投弹所致肱骨干螺旋骨折的类型及其生物力学意义。方法 分析 4 6例肱骨干投弹骨折X线片 ,测量骨折部位、长度、斜面角度和骨折的螺旋弧度等形态指标。结果 4 6例肱骨干螺旋骨折均发生于中下段 ,远近段骨折线具有对称性。骨折长度均在 30mm以上 ,以 5 1～ 90mm最多 ,共 31例 (6 7 4 % )。骨折斜面角度均≤ 4 5°,其中 4 0°～ 4 5°者 4 2例 (91 3% )。骨折螺旋角度在 2 85°～ 32 6°,平均 30 5 5°(0 85个圆周 )。 4例在骨折端内侧有一螺旋蝶形骨片。结论 肱骨干投弹骨折按形态特征分为 3种类型 ,即短螺旋、长螺旋和粉碎螺旋 ,主要发生于上臂加速期 ,由扭转暴力和纵轴压缩力引起。

Objective To investigate the types of spiral fractures of the humeral shaft caused by hand grenade throwing and its biomechanical implications. Methods 46 soldiers sufferred from humeral shaft fracture through grenade throwing in military training. Their X ray films were evaluated and fracture morphological indicators such as location, length, angle and arc were measured. Results All fractures involved in the mid distal humeral shaft. The fracture lines were symmetrical in the proximal and distal parts. The length of fractures was above 30 mm, with 51～90 mm in 31 cases (67 4%). All fracture angles were fewer than 45°, with 40°～45° in 42 cases (91 3%). The spiral arc of fractures was 285°～326°with an average of 305 5 °(0 85 circle). 4 cases had a butterfly fracture piece in the medial side. Conclusion Spiral fracture of the humeral shaft due to grenade throwing can be classified into 3 types, i.e. short spiral, long spiral and comminuted spiral. It is mainly occurred in the acceleration phase of throwing, and is mainly caused by the combination of torsional and axial compressive forces.