C2-C3 Injury

C2-C3 Ligamentous Avulsion

CT – Axial and sagittal reformatted images demonstrate cortical avulsion from posterior aspect of dens and 3 mm of anterior subluxation of C2 relative to C3.

MR – Sagittal T1, T2 and IR images demonstrate disruption of ligamentum flavum and posterior longitudinal ligament at C2-C3, anterior subluxation of C2 relative to C3, and posterior interspinous edema.

Psuedo-subluxation and pseudo-dislocation are terms applied to physiologic motion of the cervical spine in children less than 8 years of age. This occurs most often at C2-C3 and to a lesser extent at C3-C4. The motion is likely related to a combination of 1) “normal” ligamentous laxity of childhood, 2) shallow angle of inclination of the facets, and 3) increased mobility of C2-C3 since it is a transition zone between the cervicocranium and the cervical spine. In order to make this diagnosis, the posterior spinolaminar line and posterior arches must be intact. While the CT at C2-C3 is normal, ligamentous disruption and soft tissue edema are demonstrated on MRI.