股骨干骨折钢板内固定后钢板断裂并原位再折的生物力学分析

目的分析股骨干骨折钢板内固定后钢板断裂并原位再折的原因.方法对1995年3月至2002年10月所收治的57例股骨干骨折钢板内固定术后钢板断裂并原位再骨折病例从生物力学角度进行分析.结果认为①具有较高弹性模量的钢板产生的应力遮挡,也导致了较多的应力集中于钢板,使其载荷增加;②钢板置于前外侧易发生断裂;③钢板长度过短,抗张力能力降低;④骨折端对合不良或钢板对侧骨皮质缺损,由于力矩作用,致应力集中于钢板;是发生钢板断裂及再折的原因.结论良好的复位,合理使用钢板,恰当的功能锻炼可以避免钢板锻裂及原位再骨折.

Biomechanics Analysis on the Plate Break and Refracture in Original Position after Internal Fixation With Plate in Femoral Shaft Fracture

Objective: To analyze the reasons of femoral shaft fracture those plates broke and refractured in original position after internal fixation. Methods: 57 cases of femoral shaft fracture those plate broke and refractured in original position after internal fixation were analyzed from the view point of biomechanics. Results: The armor plate which had higher elastic modulus brought move stress and loading on it. The plate which was in the front &outward place of femoral shaft can break easily. The plate was too short to stand the tension force. The reason of the plate break & refracture was that the fracture and fit badly, the cortical bone against the plate defected and stress concentrated on the plate with moment effect. Conclusion: It could avoid plate break and refracture with satisfactory reduction, used plate with reason, felicitous progressive exercises.