Neoplasia is a rare cause of ataxia in horses. This report describes a 2-year-old colt presented with sudden-onset ataxia in which a cervical vertebral osteosarcoma causing severe compression of the spinal cord was diagnosed. Radiological changes included a large osteolytic lesion in the vertebral body, the vertebral arch, the right cranial articular process and the right transverse process of C4, interrupting the borders of the vertebral foramen and the right transverse foramen. Myelography revealed a marked spinal cord compression. Necropsy confirmed the presence of a well-demarcated, invasive and firm mass protruding from the fourth cervical vertebral body that led to severe compression of the spinal cord. In spite of its strongly pleomorphic nature, the detection of osteoid confirmed the diagnosis of a central osteosarcoma of the combined type. To the best of our knowledge, a primary single vertebral osteosarcoma causing ataxia in a juvenile horse has not previously been reported, and findings of this case report could help in the diagnostic work-up of similar cases.

中文翻译：

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由压缩性原发性椎骨骨肉瘤引起的 2 岁马驹的脊柱共济失调

瘤形成是马共济失调的罕见原因。这份报告描述了一只 2 岁的小马，它出现了突然发作的共济失调，诊断为颈椎骨肉瘤导致脊髓严重受压。放射学改变包括椎体、椎弓、右颅关节突和C4右侧横突的大溶骨性病变，中断椎孔和右侧横孔的边界。脊髓造影显示明显的脊髓受压。尸检证实存在从第四颈椎体突出的界限分明、侵入性和坚固的肿块，导致脊髓严重受压。尽管其具有强烈的多形性，但类骨质的检测证实了联合型中央骨肉瘤的诊断。