What does the Alar Ligament Stress Test evaluate?

The Alar Ligament Stress Test specifically evaluates the integrity of the alar ligaments, which are crucial for stabilizing the upper cervical spine, particularly in relation to the atlantoaxial (AA) joint. These ligaments connect the odontoid process (or dens) of the second cervical vertebra (C2) to the sides of the foramen magnum on the base of the skull.

When the test is performed, the examiner will typically turn the patient's head while monitoring for movement of the dens. A positive result, indicating potential disruption, is characterized by abnormal movement of the dens relative to the foramen magnum, suggesting a failure in the alar ligament's ability to constrain this movement. This is important because alar ligament injuries can lead to instability and compromise the safety of the cervical spine during various activities.

While other options may involve related concepts, such as overall cervical spine stability or hypermobility at the AA joint, the specificity of the Alar Ligament Stress Test is focused on assessing the condition of the alar ligaments directly and is thus regarded as a direct examination of alar ligament continuity and function.