Articular mass fracture: a neglected cause of post-traumatic neck pain?

Fifty-one compressed distorted cervical articular masses were found in 29 patients seen at this institution over a nine-month period. The significance of these findings is discussed and it is concluded that in most instances these represented compression fractures with deformity of the articular process. Selected signs suggestive of a compressed articular mass are identified on various views. These include (1) neuroforaminal encroachment or narrowing, (2) triangular appearance of the lateral mass in the oblique view, (3) unilateral anterior displacement of the superior facet with respect to the inferior facet, (4) minor anterior subluxation of one vertebral body over another, (5) double outline sign on the lateral view, (6) abnormally visible posterior articulations on the routine AP view. The articular processes are best shown on anteroposterior angled caudad views and lateral tomography. Articular mass deformity frequently appears to be associated with persistent post-traumatic neck pain and a relationship between this deformity and primary or secondary degenerative cervical disc and joint disease is suggested.