改良空心螺钉固定股骨颈骨折的生物力学论证  

A biomechanical study of modified cannulate screws in treatment of femoral neck fracture

作　　者：吕厚辰[1] 姚琦[2] 张里程[1] 毛智[1] 赵吉吉 张立海[1] 唐佩福[1] 

机构地区：[1]北京解放军总医院骨科,100853 [2]首都医科大学附属北京世纪坛医院骨科

出　　处：《中华创伤骨科杂志》2014年第2期156-160,共5页Chinese Journal of Orthopaedic Trauma

基　　金：国家自然科学基金（81000796,30973068）;北京市科技新星资助项目（2011085）

摘　　要：目的设计一种治疗股骨颈骨折的改良空心螺钉，并评价其力学性能。方法对普通螺钉进行改良，通过有限元分析寻找最优侧孔直径、受力薄弱点，设计改良空心螺钉成品。采取成组设计，分为2组（n=40）：改良组和常规组，每组按螺钉长度不同再分为4个亚组，分别为4．5、5，0、5．5、6．0cm组，每个亚组10枚螺钉，通过三点折弯实验比较改良组与常规组4种不同长度螺钉的极限载荷。结果改良空心螺钉侧孔开口与受力方向呈30。时，所承受的载荷最大，为960N；当呈0。和60。时，所承受的载荷最低，约为500N；侧孔开口直径与所能承受的最大载荷成反比。改良组与常规组4．5、5．0、5．5cm长螺钉的极限载荷[（706．31±5．94）MPawvs（710．63±7．17）MPa、（597．87±6．81）MPaw．（603．34±6．28）MPa、（553．20±6．25）MPaw．（546．90±7．67）MPa]、断裂载荷[（861．31±8．32）MPavs．（867．23±5．82）MPa、（778．76±7．85）MPavs．（783．54±5，36）MPa、（715．29±10．54）MPam（719，87±8．12）MPa]比较差异均无统计学意义（P〉0．05）。改良组与常规组6．0cTIl长螺钥‘的极限载荷[（436．40±6．54）MPam（431．20±5．73）MPaJ比较差异无统计学意义（P〉0．05），似断裂载荷f（535．86±10．53）MPavs．（580．08±9．34）MPa）]比较差异有统计学意义（P〈0．05）。结论本研究设计的改良空心螺钉。极限载荷较常规螺钉无明冠差异，可提供与常规螺钉相似的力学件能。Objective To evaluate the mechanical property of a kind of self-modified cannulate screws for the treatment of formal neck fracture. Methods We modified conventional cannulate screws to design a new kind with a side hole in the neck. Finite element analysis was used to identify the optimal di- ameter, orientation and weak strength point of the side hole in the new cannulate screws. Forty modified cannulate screws （MCS group） in 4 even subgroups of 4 lengths （4.5 cm, 5, 0 cm, 5.5 cm and 6. 0 cm） were compared with 40 conventional cannulate screws （CCS group） in 4 corresponding even subgroups of 4 corre- sponding lengths. The uhimate load （MPa） and fracturing load （MPa） were compared between MCS group and CCS group by three-point bending mechanical tests. Results When the side hole was at the angle of 30~. MCS had the highest load, approximately 960 N; when the side hole was at the angles of 0~ and 60~, MCS had the lowest load, about 500 N. There was a reverse proportion between the diameter of the side hole and the ultimate load of the screw. There were no significant differences between 4. 5 cm, 5.0 cm and 5.5 cm sub- groups of MCS and CCS regarding ultimate load （706.31 ± 5.94 MPa versus 710. 63 ± 7. 17 MPa, 597.87 ± 6.81 MPa versus 603.34 ±6.28 MPa and 553.20 ±6.25 MPa versus 546.90 ±7.67 MPa, respectively） and fracturing load （861.31 ±8.32 MPa versus 867.23 ±5.82 MPa, 778.76 ±7.85 MPa versus 783.54 ±5.36 MPa and 715. 29 ±10. 54 MPa versus 719. 87 ± 8.12 MPa, respectively） （P〉0.05） . In the 6 cm sub- groups, there was a significant difference between MCS and CCS regarding the fracturing load （535.86 ± 10. 53 MPa versus 580.08 ± 9.34 MPa） （ P 〈 0.05）, but no significant dift^rence between MCS and CCS regarding the ultimate load （436.40 ± 6.54 MPa versus 431.20 ＋ 5.73 MPa） （ P 〉 0.05）. Conclusion Since our self-modified cannulate screws and conventional ones have similar ultimate load, the former can provide similar mechanical performance as

关 键 词：股骨颈骨折 骨钉 生物力学 

分 类 号：R687.3[医药卫生—骨科学]