McClure S R, Watkins J P, Ashman R B
Department of Large Animal Medicine and Surgery, College of Veterinary Medicine, Texas A&M University, College Station 77843-4475.
Am J Vet Res. 1994 Sep;55(9):1327-30.
Breaking strength (torque at failure) of equine third metacarpal bones, with transfixation pins placed parallel in the frontal plane and 30 degrees divergent from the frontal plane, was determined in vitro. Two transfixation pins were placed through the distal metaphysis, using a jig designed to drill the holes in the assigned configuration. Paired metacarpal bones II through IV from 12 horses were tested in torsion. The torsional moment of the force applied through the transfixation pins at failure was compared for each limb. Metacarpal bones with divergent pins were significantly (P = 0.030) stronger, compared with those with parallel pins. Metacarpal bones with parallel pins failed with longitudinal oblique fractures through a proximal bone-pin interface, whereas those with divergent pins failed with more comminuted fractures through multiple bone-pin interfaces.
在体外测定马第三掌骨的断裂强度（失效时的扭矩），其中固定针在额平面平行放置以及与额平面呈30度发散放置。使用设计用于按指定构型钻孔的夹具，将两根固定针穿过远端干骺端。对12匹马的成对第二至第四掌骨进行扭转测试。比较每个肢体在失效时通过固定针施加的力的扭矩。与平行针的掌骨相比，发散针的掌骨明显更强（P = 0.030）。平行针的掌骨通过近端骨 - 针界面出现纵向斜形骨折而失效，而发散针的掌骨通过多个骨 - 针界面出现更粉碎性的骨折而失效。
