肱骨下段内、外侧骨瓣截取后的生物力学变化

Biomechanical character variation after the dissection of medial or lateral lower part of hunerus flap

目的：评价肱骨下段内、外侧骨瓣截取后的生物力学变化。方法：选取经防腐固定的成人上肢肱骨１２ 根，应用三点弯曲的方法测试完整肱骨的弯曲刚度，然后分为２ 组，分别从内侧髁上和外侧髁上１ ．０ ｃｍ 处切取６ ．０ ｃｍ ×０ ．５ ｃｍ 的骨瓣，测试切除骨瓣后肱骨的刚度。最后分别切取６ ．０ ｃｍ ×１ ．０ ｃｍ 骨瓣后再测试刚度。结果：内、外上髁上切取６ ．０ ｃｍ ×０ ．５ ｃｍ 骨瓣后其刚度与正常肱骨相比变化不大，而截取１ ．０ ｃｍ 宽骨瓣后肱骨的刚度显著下降。结论：为保持肱骨生物力学性能不遭受破坏，利用肱骨下段骨瓣修复骨缺损时，骨瓣的切取范围应小于６ ．０ ｃｍ ×０ ．５ ｃｍ 。

To evaluate the biomechanical character of humerus after dissction of medial or lateral lower part of humerus flap. Methods:Twelve embalmed adult human humeri were selected to test the bending stiffness by three point bending test. Then the humeri were divided into two groups randomly. A bone flap of 6.0 cm×0.5 cm was dissected from the medial or lateral low part of the humerus which is 1.0 cm above the medial epicondyle or external epicondyle. Then the stiffness of humerus was test again. At last the authors dissected the bone flap of 6.0 cm×1.0 cm and tested stiffness, Results:The stiffness of the humeri after dissection of 6.0 cm×0.5 cm has no statistic significance with that of intact humeri. But it significantly decreased after the dissection enlarged to 6.0 cm×1.0 cm. Conclusions:When the bone flap of low part of humerus was used to repair the bone defect ,the dissection of flap should be less than 6.0 cm× 0.5 cm to avoid damage of biomechanical character of humerus.