Ross M W, Martin B B
Department of Clinical Studies, University of Pennsylvania, Kennett Square 19348.
J Am Vet Med Assoc. 1992 Jul 15;201(2):332-5.
Seven Standardbred horses, all pacers, with a mean age of 2.9 years (range, 2 to 4 years), had dorsomedial articular fracture of the proximal aspect of the third metacarpal bone. Fracture caused acute, unilateral, severe lameness after training or racing. Lameness was abolished by midcarpal joint anesthesia in 4 horses. Six horses had a palpable bony swelling, which caused signs of pain. Radiography revealed a nondisplaced, articular, oblique fracture extending distad toward the dorsomedial cortex for a mean distance of 28 mm (range, 15 to 40 mm). In all horses, chronic periosteal proliferative changes, seen near the distal aspect of the fracture, corresponded to palpable bony exostoses and were associated with the medial attachment of the extensor carpi radialis tendon. In 1 horse, internal fixation followed by a 6-month rest resulted in a successful outcome. All other horses were given 3 months' rest without surgery and were not lame. Five horses raced successfully and lowered the lifetime race records, 1 horse was sound and trained successfully, but died of colic, and 1 horse was not lame in early training.
7匹标准赛马，均为快步马，平均年龄2.9岁（范围为2至4岁），发生了第三掌骨近端背内侧关节骨折。骨折在训练或比赛后导致急性、单侧、严重跛行。4匹马通过腕中关节麻醉后跛行消失。6匹马有可触及的骨质肿胀，并伴有疼痛体征。X线检查显示为无移位的关节斜形骨折，向背内侧皮质远端延伸，平均距离为28毫米（范围为15至40毫米）。在所有马匹中，骨折远端附近可见慢性骨膜增生性改变，与可触及的骨赘相对应，并与桡侧腕伸肌腱的内侧附着有关。1匹马进行内固定并休息6个月后获得成功结果。所有其他马匹未经手术休息3个月，且无跛行。5匹马成功参赛并刷新了终身比赛记录，1匹马健康并成功训练，但死于绞痛，1匹马在早期训练中无跛行。
