Hereditary Spinal Deformities in Horses

Although they occur infrequently, a number of genetic conditions can cause spinal deformities in horses. The long-term health implications of each disorder can range from mild to severe. The age, gender and breed of a horse all affect the likelihood of the disorder, as well as its manifestation pattern. If you suspect your horse may have a hereditary spine abnormality, speak to your vet to receive a diagnoses, treatment and prognosis.

  1. Lordosis

    • Lordosis, also known as scoliosis, is a curvature of the spine. Horses with this abnormality are sometimes called "low backs" or "sway backs." Juvenile lordosis develops within the first year of life, affecting colts and fillies in equal numbers. Lordosis can also occur in horses over the age of 15, particularly brood mares. The curvature may be slight or extreme.

    Cervical Stenosis

    • Cervical stenosis occurs when the the spine is compressed at the cervical level. This causes gait instability, also known as wobbler syndrome. It is named such because horses affected with this disorder may seem shaky or wobbly when walking and exercising. Cervical stenosis can occur in horses of any age, gender or breed. If left untreated, cervical stenosis can lead to neurological damage.

    Occipital Atlanto-Axial Malformation

    • Occopotal Atlanto-Axial Malformation, OAAM, is a genetic disorder found almost exclusively in Arabians. This condition causes the spinal vertebrae in the neck and skull to fuse together, resulting in lack of coordination and paralysis. OAAM manifests itself within the first month of life, and can be extremely debilitating. Affected foals may have great difficulty moving, or unable to position their head correctly to nurse.

    Prognosis

    • The prognosis for lardosis depends largely on the severity of the condition. Although most horses with lardosis are still rideable, severe cases may render them less coordinated and immobile. Cervical stenosis can be treated through surgery, but affected horses are likely to experience relapses, causing deterioration of their health over time. OAAM is untreatable and terminal. As such, most affected foals do not live very long.