## Overview Fracture of the atlas (first cervical vertebra) is an uncommon traumatic injury. The atlas lacks a vertebral body and consists of a ring with broad wings; fractures may involve the dorsal arch, wings, or articular surfaces. Neurologic signs depend on fragment displacement into the spinal canal. Foals are more susceptible than adults because of incomplete ossification. ## Causes Falls over backward, collisions, and kicks are the usual causes. Hyperflexion or hyperextension of the cranial neck transmits force to the atlas. ## Diagnosis Acute neck pain, swelling, abnormal head carriage, and variable ataxia follow trauma. Radiographs may reveal the fracture, but computed tomography is often required for complete characterization, especially of minimally displaced or articular fractures. ## Treatment Stable, minimally displaced fractures are managed with stall rest and anti-inflammatory medication. Unstable fractures or those causing progressive neurologic deficits may require surgical stabilization when feasible. External coaptation is rarely practical in adult horses. ## Recovery and Prognosis Prognosis correlates with the degree of spinal-cord compression and fracture stability. Horses with minimal displacement and no or mild ataxia can recover fully. Severe cord damage carries a guarded to grave prognosis. ## Prevention Minimizing situations that lead to falls over backward or high-speed collisions.
acute neck pain after trauma; swelling over the poll or cranial neck; abnormal head carriage; ataxia of variable severity
## Overview Fracture of the atlas (first cervical vertebra) is an uncommon traumatic injury. The atlas lacks a vertebral body and consists of a ring with broad wings; fractures may involve the dorsal arch, wings, or articular surfaces. Neurologic signs depend on fragment displacement into the spinal canal. Foals are more susceptible than adults because of incomplete ossification. ## Causes Falls over backward, collisions, and kicks are the usual causes. Hyperflexion or hyperextension of the cranial neck transmits force to the atlas. ## Diagnosis Acute neck pain, swelling, abnormal head carriage, and variable ataxia follow trauma. Radiographs may reveal the fracture, but computed tomography is often required for complete characterization, especially of minimally displaced or articular fractures. ## Treatment Stable, minimally displaced fractures are managed with stall rest and anti-inflammatory medication. Unstable fractures or those causing progressive neurologic deficits may require surgical stabilization when feasible. External coaptation is rarely practical in adult horses. ## Recovery and Prognosis Prognosis correlates with the degree of spinal-cord compression and fracture stability. Horses with minimal displacement and no or mild ataxia can recover fully. Severe cord damage carries a guarded to grave prognosis. ## Prevention Minimizing situations that lead to falls over backward or high-speed collisions.
acute neck pain after trauma; swelling over the poll or cranial neck; abnormal head carriage; ataxia of variable severity