经胸腰段伤椎单节段椎弓根螺钉固定后的生物力学特性  

Biomechanical properties of monosegmental pedicle screw fixation via the fractured thoracolumbar vertebrae

作　　者：刘上楼[1] 徐军[1] 倪卓民[1] 张云庆[1] 周枫[1] 姜雪峰[1] 

机构地区：[1]江阴市人民医院骨科,江苏省江阴市214400

出　　处：《中国组织工程研究》2013年第39期6908-6913,共6页Chinese Journal of Tissue Engineering Research

摘　　要：背景:临床常采用经伤椎椎弓根螺钉内固定治疗胸腰椎骨折,研究已证实经伤椎双侧椎弓根螺钉固定后脊柱稳定性加强,但也有研究认为经伤椎单节段椎弓根螺钉固定足以增加脊柱的稳定性,但此结论缺乏生物力学结果支持。目的:观察胸腰段椎体骨折经伤椎单节段固定的相关生物力学特性。方法:取扬州大学医学院解剖教研室提供8具中国人新鲜胸腰段标本(T11-L3),锯条横断2/3椎体,制成完整胸腰段椎体实验标本,将8具标本等分成跨伤椎固定组和单节段经伤椎固定组,分别在跨伤椎临近椎体四钉固定和临近椎体四钉固定+经伤椎单侧椎弓根固定。结果与结论:胸腰段椎体骨折后经跨伤椎固定与经单节段伤椎固定的载荷-应变关系相差12%、载荷-位移关系相差11%、强度相差18%、轴向刚度相差11%、扭转力相差11%及拔出力相差1.8%,两组差异有显著性意义(P<0.05),说明经伤椎单节段固定胸腰段椎体骨折的生物力学性能更好。BACKGROUND：In clinic, monosegmental pedicle screw fixation via the fractured vertebrae is commonly used for the treatment of thoracolumbar fracture. Studies have confirmed that the spinal stability is strengthened through bilateral pedicle screw fixation via fractured vertebrae, but some studies suggest that monosegmental pedicle screw fixation via fractured vertebrae can increase the spinal stability, and the conclusion lacks of the supports of biomechanics. OBJECTIVE：To evaluate the biomechanical properties of monosegmental pedicle screws fixation via fractured vertebrae for thoracolumbar fracture. METHODS：Eight cadavers’ thoracolumbar specimens （T11-L3） were provided by the Department of Anatomy, Yangzhou University School of Medicine. Saw was used to transect 2/3 of the vertebrae in order to make complete experimental thoracolumbar specimens. Eight specimens were divided into two group;beyond-fractured vertebrae fixation group and monosegmental fixation via fracture vertebrae group. The specimens in the two groups were treated with adjacent vertebral four screw fixation beyond fractured vertebrae and adjacent vertebral four screw fixation＋monosegmental pedicle screw fixation via fractured vertebrae respectively. RESULTS AND CONCLUSION：After thoracolumbar fracture, the differences between beyond fractured vertebrae fixation and monosegmental pedicle screw fixation via fractured vertebrae were as fol ows：load-strain relationship 12%, load-displacement relationship 11%, strength 18%, axial rigidity 11%, torsional mechanical properties 11%and pul out test 1.8%, and there were no significant differences between two groups （P〈0.05）. The biomechanics performance of monosegmental pedicle screw fixation via fractured vertebrae was more superior to that of pedicle screw fixation beyond the fracture vertebra for thoracolumbar fracture.

关 键 词：骨关节植入物 人工假体 胸腰椎骨折 经伤椎椎弓根 椎弓根螺钉 单节段固定 生物力学 载荷 

分 类 号：R318[医药卫生—生物医学工程]