小转子二分型的难复位股骨转子间骨折手术技巧及疗效分析

Two-part pertrochanteric femur fractures with bisection of the lesser trochanter： an irreducible fracture pattern with soft tissue interposition

关键词:  股骨转子间骨折  小转子  难复位  软组织嵌顿  髂腰肌腱

Key words:  pertrochanteric fractures  lesser trochanter  irreducible  soft-tissue interposition  iliopsoas tendon

摘要:

目的探讨小转子上下二分型难复位股骨转子间骨折的手术技巧及疗效。方法收集2017年1月—2019年12月同济大学附属杨浦医院手术治疗的股骨转子间骨折357例，其中6例为小转子上下二分型的股骨转子间两部分骨折，收集患者临床资料。分析其骨折病理特征、难复位原因、手术复位技巧及治疗效果。结果小转子二分型的股骨转子间骨折，多发生于中年和相对年轻的老年人。6例均手法复位不能成功，经有限切开复位、头髓钉内固定，均获得优良的治疗效果。其病理形态学特征包括： 骨折线经小转子中点平面，将小转子分成几乎相等的上下两半，近侧半与头颈骨块相连呈长尖齿状，有腰大肌腱附着，呈屈曲外旋外翻移位；远侧半与股骨干相连，有髂肌腱附着，向上短缩、内旋移位；因外上角的骨性交锁和内下角的软组织嵌顿（髂肌），致使骨折难以复位。结论小转子上下二分型的股骨转子间骨折，闭合手法复位难以成功，术中只有解除骨性交锁和软组织嵌顿，骨折才能获得满意的复位和内固定。

Abstract:

ObjectiveTo introduce a new type of irreducible pertrochanteric femur fracture pattern with bisection of the lesser trochanter. MethodsFrom 2017 to 2019, we performed the operation with closed reduction and internal fixation for per/inter-trochanteric femur fractures in 357 cases, and 6 patients(1.7%, 4 male and 2 female, average age 60.5 years) were irreducible by closed maneuver in two-part pertrochanteric fractures that the fracture line passing through the mid-portion of the lesser trochanter. The characteristics of fracture patho-anatomy, reasons of irreducibility, intraoperative techniques and treatment results were summarized. ResultsThis unique fracture pattern occurred in middle-aged and relatively young elderly patients. After limited open reduction and cephalomedullary nailing, all patients achieved satisfied fracture reduction quality and excellent stability after internal fixation. The characteristics of the fracture patho-anatomy were that the lesser trochanter was fractured and separated into two parts almost equally. The upper portion of lesser trochanter was a part of the proximal head-neck fragment, which was attached with the psoas tendon, and deformed to a flexion-external rotation and valgus position. While the lower portion of lesser trochanter was a part to the distal femur shaft, which was attached with ilioas tendon, and deformed to a proximal shortening and internal rotation position. The cause for fracture irreducibility was fragment cortical locking at the upper lateral corner and ilioas muscle interposition at the lower medial corner, with its tendon remains attached to the distal portion of the lesser trochanter with the femur shaft. ConclusionTwo-part pertrochanteric femur fractures with bisection of the lesser trochanter is an irreducible fracture pattern with cortical locking and soft tissue interposition. Only if these osseous and elastic locking factors are solved, can the fracture be reduced and fixed with satisfaction.