桥接系统混棒与双棒结构治疗股骨及胫骨骨折的生物力学特点

《中国组织工程研究》 Chinese Journal of Tissue Engineering Research
桥接系统混棒与双棒结构治疗股骨及胫骨骨折的生物力学特点
·研究原著·
汪 亮1，黄朝朝2，于娇娜2，顾卫东1，王 忍1，钱志艺1 (1常州市第七人民医院骨科，江苏省常州市
有限公司牛顿实验室，天津市 301600)
摘要 背景：桥接系统双棒结构为偏心固定，术后可能导致纵向上固定减弱及横向上抗扭转降低。 目的：比较桥接组合式内固定系统混棒与双棒结构治疗股骨及胫骨骨折的生物力学特性。 方法：以 40 根短聚甲醛材料配对模拟人体长骨骨干模型 20 个，其中 10 个以桥接组合式内固定系统混棒结 构固定(混棒结构组)，另 10 个以桥接组合式内固定系统双棒结构固定(双棒结构组)，对 2 组分别进行轴向压 缩实验和径向扭转实验(每种实验各选择每组 5 个模型)，观察 2 组的轴向压缩力与位移情况，以及横向扭转 力与角度变化，记录各组曲线出现折点或趋于水平状态时的载荷即最大载荷，并计算屈服载荷。 结果与结论：①当轴向压缩屈服载荷≤2 000 N、产生相同位移时，混棒结构组所需轴向压缩屈服载荷大于 双棒结构组；当轴向压缩屈服载荷>2 000 N、产生相同位移时，双棒结构组所需轴向压缩屈服载荷大于混 棒结构组，并且双棒结构组最大轴向压缩屈服载荷大于混棒结构组[(2 420.60±5.67)，(2 721.40±5.80)N， t=-82.885，P=0]；②当径向扭转屈服载荷≤50 N•m、产生相同角度时，混棒结构组所需的扭矩小于双棒结 构组；当径向扭转屈服载荷>50 N•m、产生相同角度时，混棒结构组所需扭矩大于双棒结构组，并且混棒结 构组最大径向扭转屈服载荷大于双棒结构组 [(101.85±2.97)，(85.41±2.82)N•m，t=8.985，P=0]；③结果说 明，桥接系统混棒与双棒结构纵向上均可坚强固定骨折，但混棒结构固定骨折更稳定、牢靠，更容易促使骨 折愈合；混棒结构横向上固定骨折后，骨折端容易产生微动，符合弹性固定，并且最大抗扭转力及抗疲劳性 能优于双棒结构，可防止因横向不稳定造成的桥接系统断裂。 关键词： 桥接组合式内固定系统；双棒结构；混棒结构；生物力学；股骨与胫骨骨折；屈服载荷；轴向压缩 中图分类号：R459.9；R318.01；R-331 基金资助： 国家卫计委科技发展中心项目《桥接系统治疗四肢及骨盆骨折的临床研究》(W2015QJ045)，项目负责人： 顾卫东
Wang Liang1, Huang Zhaozhao2, Yu Jiaona2, Gu Weidong1, Wang Ren1, Qian Zhiyi1 (1Department of Orthopedics, the Seventh People's Hospital of Changzhou, Changzhou 213011, Jiangsu Province, China; 2Newton Laboratory, Tianjin Weiman Biomaterials Co., Ltd., Tianjin
Biomechanical characteristics of bridge-link type combined internal fixation system with mixed-rod versus double-rod in the treatment of femoral and tibial fractures
汪亮，男，1986 年生，安 徽省铜陵市人，汉族，2016 年安徽医科大学毕业，硕 士，医师，主要从事四肢 及骨盆骨折方面的研究。
通讯作者：顾卫东，主任 医师，常州市第七人民医 院骨科，江苏省常州市 213011
文献标识码:B 投稿日期：2018-11-01 送审日期：2018-11-10 采用日期：2018-12-08 在线日期：2019-03-05
(1)轴向压缩力与位移情况； (2)横向扭转力与角度变化； (3)记录各组曲线出现折点或趋
于水平状态时的载荷即最大
载荷，计算屈服载荷。
结局意义：
(1)桥接系统混棒与双折更稳定、牢靠，更 容易促使骨折愈合；
(2)混棒结构骨折固定后，横向上骨折端容易产生微动，符合弹性固定，且抗疲劳性能优于双棒 结构。
DOI:10.3969/j.issn.2095-4344.1189
ORCID: 0000-0002-0608-5303(汪亮)
213011；2天津市威曼生物材料
文章快速阅读：
文章特点— (1)桥接组合式内固定系统采用双棒固定骨折时，由于双棒结构为偏心固定，可能导致纵向上固定减
弱及横向上抗扭转降低； (2)采用桥接组合式内固定系统固定骨折，比较混棒结构与双棒结构固定的生物力学差异。
Wang Liang, Master, Physician, Department of Orthopedics, the Seventh People's Hospital of Changzhou, Changzhou 213011, Jiangsu Province, China
Corresponding author: Gu Weidong, Chief physician, Department of Orthopedics, the Seventh People's Hospital of Changzhou, Changzhou 213011, Jiangsu Province, China
文题释义： 桥接系统双棒与混棒结构：桥接系统双棒结构类似于锁定钢板，固定骨折方式为平行一侧骨面的偏心固定， 但偏心固定可能导致纵向上固定减弱及横向上抗扭转降低，骨折端固定不牢靠而使骨折不易愈合，甚至内固 定疲劳失效。桥接系统混棒结构为一根单棒固定骨折后，在其径向 90°或 135°处固定另一根单棒，实现非 平面整体、立体固定，骨折端纵向上坚强固定，横向上抗疲劳性能强。 轴向压缩与径向扭转实验：轴向压缩实验是以 3 mm/min 的速度向模型两端施加轴向压力，观察轴向压缩屈 曲载荷与骨折端位移的变化；径向扭转实验是以 2 r/min 的速度径向旋转，观察横向扭矩与角度变化。轴向 压缩实验主要观察纵向上骨折端稳定程度，径向扭转实验主要观察横向上抗疲劳性能。
301600, China)
Abstract BACKGROUND: The double-rod of bridge-link type combined internal fixation system belongs to eccentric fixation, which may lead to the weakening of longitudinal fixation and the decrease of transverse anti-torsion after operation. OBJECTIVE: To compare the biomechanical characteristics of bridge-link type combined internal fixation system with mixed-rod and double-rod in the treatment of femoral and tibial fractures. METHODS: Twenty human long bone diaphysis models were made by 40 short polyformaldehyde materials. Of these, 10 were fixed by mixed-rod, and the rest with bridge-link type combined internal fixation system. Axial compression tests and radial torsion tests were carried out (five models were selected from each group). The changes of axial compression forces and displacements and transverse torque and angle were observed. The maximum load was recorded when the curve had a break point or in a horizontal state, and then the yield load was calculated. RESULTS AND CONCLUSION: (1) When the axial compression load was ≤ 2 000 N, and with same displacement, the axial compression yield load in the mixed-rod group was larger than that in the bridge-link type combined internal fixation system group. When the axial compression load was > 2 000 N, and with the same displacement, the axial compression yield load in the bridge-link type combined internal fixation system group was larger than that in the mixed-rod group. The maximum axial compression yield load in the bridge-link type combined internal fixation system group was larger than that in the mixed-rod group [(2 420.60±5.67), (2 721.40±5.80) N, t=-82.885, P=0]. (2) When the radial torsional yield load was ≤ 50 N•m, and with the same angle, the torque in the mixed-rod group was less than that in the bridge-link type combined internal fixation system group. When the radial torsional yield load was > 50 N•m, and with the same angle, the torsion in the mixed-rod group was greater than that in the bridge-link type combined internal fixation system group. The maximum radial torsional yield load in the mixed-rod group was larger than that in the bridge-link type combined internal fixation system group [(101.85±2.97), (85.41±2.82) N•m, t=8.985, P=0]. (3) These results indicate that the mixed-rod and of bridge-link type combined internal fixation system can be used to fix the fractures strongly, but the mixed-rod is more stable and reliable, thus it is easier to promote fracture healing. The fracture end is easy to create slight movement after the fracture is fixed with transverse mixed-rod, which is in accordance with elastic fixation. The maximum anti-torsion and anti-fatigue performance is better than the double-rod, which prevents from breakage. Key words: bridge-link type combined internal fixation system; double-rod; mixed-rod; biomechanics; femoral and tibial fractures; yield load; axial compression Funding: the Project of Development Center for Medical Science and Technology National Health and Family Planning Commission of China, No. W2015QJ045 (to GWD)