Intervertebral Joint Osteoarthritis

Osteoarthritis Draw

Fig. 8.37a This misalignment at the L4/L5 level is caused by degenerative disk disease and degenerative changes in the posterior elements of the spine, the intervertebral joints. Because it is not due to a defect of the pars interarticularis of the vertebral body, it is also called pseudospondylolis-thesis or degenerative spondylolisthesis by some. The whole L4 vertebral body including the spinous process and the body itself has moved ventrally relative to L5. b If you draw one line along the anterior margins of the vertebral bodies and another one along the spinous processes, it becomes clear that the displacement concerns the whole vertebral body—quite the opposite to what one can see in true spondylolisthesis associated with spondylolysis (see Fig. 8.43a).

Spinal canal stenosis: A stenosis of the spinal canal (Fig. 8.38) can cause diffuse back pain. It is verified by CT or MR.

Scoliosis: In scoliosis—a curvature of the spine in the form of an S that may also include a rotational component (Fig. 8.39)—altered biomechanics of the spine lead to accelerated degeneration of the intervertebral disks. (By the way, which other relevant finding is present on this radiograph?)

Intervertebral disk prolapse: A circumscribed disk prolapse can cause diffuse back pain. The standard lumbar radiograph may, however, be entirely normal in these cases (Fig. 8.40a). A CT (Fig. 8.40b) or MRI is indispensable to substantiate the diagnosis, the latter representing the current gold-standard for spinal imaging.

Spondylodiskitis: This entity is an acute inflammation of the disk space that was frequently caused by mycobac-

terial infection (tuberculosis) in the past but that may be due to a large number of different bacteria nowadays, with Staphylococcus aureus taking the lead. The disk literally melts away in this condition and the neighboring vertebral end plates are also destroyed (Fig. 8.41). Sometimes the differentiation from degenerative disease is not trivial, but a vacuum phenomenon excludes an inflammatory nature for all practical purposes.

To verify diskitis and to establish the extent and spread of the disease preoperatively, MRI is obligatory because it also shows the frequent perivertebral abscesses, especially in the spinal canal (Fig. 8.42a, b). Imaging should include MR sequences without and with intravenous contrast administration and fat suppression. If abscesses form outside the spinal canal, they can descend along the rim of the psoas muscle and reach down into the inguinal region. If percutaneous drainage is necessary, it is often performed under CT guidance (Fig. 8.42c).

0 0

Post a comment