舟骨骨折的螺钉居中固定：生物力学试验  

Central placement of screw fixation for scaphoid fracture:a biomechanical study

作　　者：郭阳[1] 田光磊[1] 姜保国[2] 陈山林[1] 韩娜[2] 

机构地区：[1]北京积水潭医院手外科,北京100035 [2]北京大学人民医院创伤骨科、北京大学交通医学中心,北京100044

出　　处：《北京大学学报（医学版）》2013年第5期684-687,共4页Journal of Peking University:Health Sciences

摘　　要：目的:对于斜形不稳定的舟骨骨折,通过生物力学试验评价舟骨螺钉的位置居中与否对其固定强度的影响。方法:将32例外形、材质相同的Sawbone舟骨分为4组,每组8例,模拟腰部骨折,用螺钉固定,分组依据骨折的水平(远、近)及螺钉的位置(居中、不居中)。对其中的1例Sawbone舟骨进行CT扫描,流量数据导入术前设计与手术模拟软件(VxWork 4.0),建立舟骨的中央区,同时在软件中设计骨折模拟平面、螺钉导针位置。将螺钉固定后的舟骨置于生物力学试验机平台,测量不同试验组标本固定失效时的最大负荷及位移。结果:不同组间固定失效时的最大负荷和位移有统计学差异(F=31.485,P=0.001;F=33.328,P=0.018)。对于腰部偏近端的骨折,居中组与非居中组最大负荷[(80.82±15.63)N vs.(58.32±17.18)N]及位移均值[(2.3±0.5)mm vs.(3.1±0.5)mm]差异有统计学意义(P均<0.001);对于腰部偏远端的骨折,居中组最大负荷及位移优于非居中组[(76.83±14.54)N vs.(70.38±13.32)N;(2.2±0.7)mm vs.(2.5±0.6)mm],但二者差异无统计学意义。结论:本次生物力学研究表明,对于舟骨斜形不稳定骨折,将螺钉在舟骨内居中放置可以提供更高的固定强度。Objective：To evaluate the effect to the fixation stability of central screw placement during scaphoid fracture surgery. Methods： We designed oblique osteotomies for 32 identical sawbone scaphoids and fixed each specimen with a cannulated screw. Sawbone scaphoids were divided into 4 groups, ac- cording to position of the osteotomy （ distal waist portion or proximal waist portion） and the position of the screw （central or eccentric）. We performed Computed Tomography scanning to one specimen, and then the central zone of the scaphoid was established from volume data by using the preoperative planning sys- tem software （VxWork 4.0）. The position of the osteotomy plane, the entrance and exit points of the screw guide pin were designed on the software as well. We placed the specimens under the increasing load of a pneumatically driven plunger to compare the load to failure and the distance at failure between the central and eccentric screw groups. Results： In general, we found the statistical differences of the load to failure and the displacement of fracture between the groups （ F = 31. 485, P = 0. 001 ; F = 33. 328, P = 0. 018 ）. The average load to failure and fracture displacement was more statistically different in the central group [ （80.82 ± 15.63） N, （2.3 ±0.5） mm] for proximal waist fracture than in the eccentric group [ （58.32 ± 17.18） N, （3.1 ±0.5） mm]. As to the distal waist fracture, the average load to failure and fracture displacement was better in the central group [ （76.83 ± 14.54） N, （2.2 ± 0.7） mm] than in the eccentric group [ （70.38 ± 13.32） N, （2.5 ±0.6） mm] without significant difference. Conclusion： In this biomechanieal model of an unstable oblique scaphoid fracture, we find that higher stability of fixation has been achieved with a screw placed centrally in the scaphoid, compared with a screw peripherally placed.

关 键 词：舟骨 骨折固定术 内 生物力学 

分 类 号：R683.41[医药卫生—骨科学]