Acquired Torticollis

Robert J. MacKay • Mary O. Smith

Primary acquired torticollis with or without neurologic disease occurs in all species of domestic livestock. Causes include fracture or subluxation of the cervical vertebrae, basilar skull fractures, dystrophic muscle degeneration, unilateral cicatricial muscular contracture from injections, lupinosis, traumatic rupture of the cervical muscles, parasitic migration through the cervical spinal cord, hydranencephaly, asymmetric neurodegeneration, and congenital vertebral deformity.^1-6 In one study, researchers hypothesized that physical constraint within the narrow tips of uterine horns caused acquired torticollis and a variety of other deformities such as head scoliosis and limb malformations in more than 200 foals.⁷ Draft horses may be predisposed to this problem, which frequently results in severe dystocia in horses.

Treatment of traumatic torticollis should be directed at reducing the edema, relieving pain, and immobilizing the damaged structures. Muscular tears may be treated by encas­ing the head, neck, and proximal thorax in a fiberglass cast. Ancillary supportive treatment may include dexamethasone (0.05 to 0.1 mg/kg IM or IV daily for 2 to 3 days), methocarbamol (8 mg/kg IV tid for 5 days), and NSAIDs (e.g., phenylbutazone 2 mg/kg bid PO or IV or flunixin meglumine 1.1 mg/kg IV bid for 3 to 5 days after injury). A method of surgical correction of cervical muscle contractures through a muscle-splitting procedure has been described⁹; however, this seems unnecessary because most animals recover with only medical treatment. When torticollis is the cause of equine dystocia, delivery of the foal by cesarean section is often followed by rapid and complete anatomic and functional recovery.⁷