Abstract
Radiological changes of the posterior elements in the lower cervical spine of 40 surgically-treated RA patients were studied. Erosion of the apophyseal joint was seen at 88 intervertebral segments (44 %) of 31 cases. These were often seen at the posterior part of the joint with eroded inferior articular processes, in which the inclination angle of the facet was increased. Spinous process erosion was seen at 58 spinous processes (26%) of 16 cases, and this was classified into 3 groups: partial erosion of upper or lower margins of the spinous process, total erosion of spinous process margins, and erosive shortening of the spinous process, ie apical erosion. There was severe extensive erosion of the apophyseal joint and the spinous process in 3 cases, in which a constricting band of the dura mater was observed at the same level. Spinous process erosion including apical erosions may have a close relationship with spinous process impingement and anterior subluxation of the lower cervical spine.
