基于杠杆重建理论对长骨干骨折内固定治疗的新认识  

A new understanding of internal fixation for long shaft fractures--lever reconstruction theory

作　　者：张殿英[1] Zhang Dianying(Department of Orthopaedics and Traumatology,National Center for Trauma Medicine,Key Laboratory of Ministry of Education for Trauma Treatment and Nerve Regeneration,Peking University People's Hospital,Beijing 100044,China)

机构地区：[1]北京大学人民医院创伤骨科,国家创伤医学中心,创伤救治与神经再生教育部重点实验室,北京100044

出　　处：《中华骨科杂志》2022年第5期265-271,共7页Chinese Journal of Orthopaedics

基　　金：教育部创新团队项目(IRT_16R01);北京大学医学部学院建设项目(2020)-国家创伤医学中心(BMU2020XY005-01);北京大学医学部学院建设项目(2020)-创伤救治与神经再生教育部重点实验室(BMU2020XY005-03)。

摘　　要：通过对长骨干生理解剖及生物力学特点的研究得出长骨干在骨折内固定后形成杠杆系统,即骨折线和内固定交点为杠杆支点,施加外力作用点到支点的距离为动力臂,支点到内固定尾端与骨质接触点的距离为阻力臂,内固定所需长度应尽量使动力臂和阻力臂相等,此为杠杆重建理论。治疗长骨干骨折常用钢板及髓内钉固定。髓内钉主要是依靠主钉与髓腔内壁的接触,以及远端锁钉与骨质接触的牢固程度发挥作用。根据杠杆重建理论,髓内钉固定后动力臂为施加外力作用点到支点的距离,阻力臂为支点到髓内钉尾端与骨质接触点的距离;术中置入髓内钉前应予以充分扩髓,并使用较大直径的主钉,使之与内壁紧密贴合,并通过远端锁钉增加骨质接触把持,延长有效工作距离。钢板固定是依靠远端螺钉与骨质的把持力,可增加固定的可靠性,其动力臂为施加外力作用点到支点的距离,阻力臂为支点到对侧钢板末端的距离。骨折位置不同,形成的杠杆种类不同,如动力臂小于或等于阻力臂,可形成费力杠杆或平衡杠杆,结构稳定;当动力臂大于阻力臂时,为省力杠杆,任何内固定都无法实现绝对稳定,易出现骨折不愈合或内固定失效等并发症,此时应尽可能延长阻力臂的有效工作距离,并针对不同骨折类型进行科学有效的康复指导。该理论很好地解释了长骨干骨折术后发生内固定相关并发症的原因,为长骨干骨折的治疗指明了新方向。Through the study of the anatomy and biomechanical characteristics of the long bone after internal fixation of fracture,researches showed that a new level system is formed.The intersection of fracture line and internal fixation serves as the fulcrum.The distance from external force point to fulcrum is power arm,and the distance from the fulcrum to the tail of internal fixation contacting bone is the resistance arm,and the power arm and resistance arm should be as equal as possible.This is the lever reconstruction theory.Plate and intramedullary nail fixation are commonly used in the treatment of long shaft fractures.The intramedullary nail mainly depends on the contact between the main nail and the inner wall of the medullary cavity,and the firmness of distal locking nail and the bone.According to the lever reconstruction theory,after intramedullary nail fixation,the power arm is the distance from the point of external force to the fulcrum,and the resistance arm is the distance from the fulcrum to the contact point of nail tail and bone.The intramedullary nail should be fully reamed before inserting and the main nail with larger diameter should be used to make it closely fit with the inner wall,and contact should be increased through distal locking to prolong the effective working distance.Plate fixation depends on the holding force between the distal screw and bone,which can increase the reliability of fixation.The power arm is the distance from the point of external force to the fulcrum,and the resistance arm is the distance from the fulcrum to the end of the opposite side.The type of lever formed varies with the location of the fracture.For example,if the power arm is shorter than or equal to the resistance arm,it can form a laborious lever or balance lever with stable structure.When the power arm is longer than the resistance arm,absolute stability cannot be achieved and it is prone to complications such as nonunion and fixation failure.At this time,effective working distance of the resistance arm should be e

关 键 词：长骨干骨折 髓内钉固定 生物力学特点 动力臂 骨折位置 骨折线 生理解剖 骨折内固定 

分 类 号：R687.3[医药卫生—骨科学]