Subtle subluxations can be difficult to distinguish from normal range of interfacetal motion, and other imaging and clinical findings should be considered prior to diagnosis. Facetal injuries may be associated with other hyperflexion injuries such as hyperflexion sprains, wedge compression fractures, or hyperflexion teardrop fractures. Axial CT section through the superior intervertebral foramina of C6-7 demonstrates normal facet alignment on the left. The right C6-7 intervertebral foramen is asymmetrically widened. The subluxation is apparent when the interfacetal joint is compared to the levels above and below the injury.
Dislocation is either unilateral or bilateral.
Additionally, UID is associated with damage to both the posterior and middle ligamentous support columns. Clinically, UID is associated with neck pain. Radiculopathy at the level of the involved foramen, spinal cord injury, ipsilateral vertebral artery injury, and occasional posterior fossa stroke can also occur. Occasionally, however, these injuries produce mild or minimal symptoms, resulting in delay of diagnosis. Treatment can be either traction with closed reduction or cervical fusion, depending on the severity of the injury and ability to obtain anatomic alignment.