Hindlimb paresis associated with kyphosis, hemivertebrae and multiple thoracic vertebral malformations in a Quarter Horse gelding

Congenital kyphosis secondary to lumbar vertebral hypoplasia causing paraparesis in a Friesian foal

“…Although there are a number of reports on congenital vertebral developmental abnormalities and malformations in the cervical (Wilson et al 1985;Rosenstein et al 2000;Nixon 2002;Bell et al 2007) and thoracic regions (Lerner and Riley 1978;Jeffcott 1980;Kirberger and Gottschalk 1989b;Ryan et al 1992;Harmelin et al 1993;Doige 1996;Johnson et al 1997;Wong et al 2005Wong et al , 2006 this is, as far as…”

“…1993; Doige 1996; Johnson et al . 1997; Wong et al . 2005, 2006) this is, as far as the authors are aware, the first report in the literature, that describes a congenital lumbar vertebral malformation in the horse that resulted in kyphosis and apparent lumbar spinal cord compression with accompanying neurological deficits.…”

“…These result from a failure during the formation of the primordial vertebrae or a defect in the ossification of the vertebral body. In horses they have been observed in the cervical and thoracic vertebral column, whereas in other species the T7 and T9 sites are most commonly affected (Wong et al 2005;Rush 2006). Another type of vertebral malformation is the occurrence of block vertebrae that result from incomplete separation of the vertebral bodies or arches, or both.…”

Thoracolumbar malformations or injuries and neurological manifestations

“…In the report above, Wong et al (2005) present a well documented and unusual case of congenital malformation of the thoracic spine inducing hindlimb paresis. The specimens shown in museums of old veterinary schools (e.g.…”

Congenital Malformation of the Nervous System

“…Hemivertebrae are wedge-shaped vertebrae in which the apex may be directed ventrally, laterally, or dorsally, resulting in kyphosis, scoliosis, or lordosis. 16,17 Hemivertebrae and multiple thoracic vertebral abnormalities were found in a Quarter Horse foal which presented for a long-standing hind limb ataxia when it was five months and which had recently worsened. 17 There was severe kyphosis at the midthoracic level, with fusion of the dorsal spinous processes of T4-T8.…”