Ischemic myelopathy caused by fibrocartilaginous embolism in a horse

Abstract

This report described clinical, epidemiological, and pathological aspects of ischemic myelopathy caused by fibrocartilaginous embolism (FCE) in a 10-year-old, mixed breed gelding. Clinically, the horse presented acute hind limbs paralysis, with a clinical course of approximately 24 hours. At necropsy, no gross lesions were observed. Cross-sections of the spinal cord revealed focally extensive areas of malacia from the T10 to L4 segments. Focally extensive areas of liquefactive necrosis involving the gray matter and adjacent white matter were observed on histologic sections. The lumen of multiple blood vessels in the periphery of the necrotic areas was occluded by fibrocartilaginous emboli that strongly stained with alcian blue. Clinical signs, gross necropsy, and histological findings observed in this case were identical to those described in the literature for ischemic myelopathy caused by FCE in the horse and other species.

Pathology in Practice

“…Neurologic signs can vary according to the anatomic location of the emboli and the extension of the lesion in the central nervous system. 11 The clinical signs of the pony of the present report were similar to a case described by Panziera et al, 13 which to our knowledge is the only reported case with thoracic spinal cord lesion and paralysis of the pelvic limbs. The other reports are from cases of cervical spinal lesions with consequent paralysis of the thoracic and pelvic limbs.…”

“…17,18 Previous reports in horses did not show breed predisposition, but most were males and older than 8 years old. [10][11][12][13] Those findings support the existence of predisposing factors such aging of the fibrocartilaginous ring or its fissure, leading to intravascular herniation of the material. 18 Trauma and intensive exercise are also risk factors for the development of fibrocartilaginous myelopathy.…”

“…This condition has been described in cattle, 1 dogs, 2,3 cats, 4 swine, 5 tigers, 6 turkeys, 7 and humans. 8 It is a rare disease in horses, [9][10][11][12][13] and to our knowledge, this is the first report in a pony.…”

“…11 Therefore, this condition should be considered in the list of differential diagnosis for neurologic signs consistent with spinal cord lesions in horses and ponies. 10,11,13…”