A fractured transverse process, which is almost always the result of high-impact rotary injury of the spine, causes tearing of the paravertebral muscles and a local hematoma, producing deep tenderness at the site of the injury and limitation of all movements that stretch the lumbar muscles. The imaging findings, particularly MRI, confirm the diagnosis. In some circumstances, tears of the paravertebral musculature may be associated with extensive bleeding into the retroperitoneal space; this produces paraspinal or groin pain and proximal leg weakness with loss of the patellar reflex on the affected side. There may be a delayed subcutaneous hematoma in the flanks due to seepage of blood from the retroperitoneal space (Grey-Turner sign).
For the mundane thoracic and lumbar fracture associated with osteoporosis, bed rest, and analgesics are usually adequate. In the past two decades several mechanical approaches to reducing pain have been investigated. The injection of various materials directly into the fracture site within the vertebral body (vertebroplasty) attained popularity because of reports of marked pain relief. Several large trials have addressed the use of vertebroplasty and given conflicting results. The best conducted of these, with a placebo control group (see Buchbinder et al and Kallmes et al) concluded that there was no durable benefit; however, these two studies included patients with fractures up to a year old and the studies apply specifically to osteoporotic fractures. Having witnessed a few patients with almost immediate and remarkable relief of severe pain, we are uncertain of the best course but acknowledge that this is probably not an effective treatment for the majority of patients. Further discussion can be found in the review by Ensrud and Schousboe.
Herniation of Lumbar Intervertebral Discs (Table 10-1)
This condition is a major cause of severe and chronic or recurrent low back and leg pain. It occurs mainly during the third and fourth decades of life when the nucleus pulposus is still gelatinous. The disc between the fifth lumbar or first sacral vertebrae (L5-S1) is most often involved, and, with decreasing frequency, that between the fourth and fifth (L4-L5), third and fourth (L3-L4), second and third (L2-L3), and—quite infrequently—the first and second (L1-L2) lumbar vertebrae. Disc disease is relatively rare but well described in the thoracic portion of the spine. It is frequent in the cervical spine, especially at the fifth and sixth and the sixth and seventh cervical vertebrae (see further on).
The likely cause of a herniated lumbar disc is a flexion injury, but a considerable proportion of patients do not recall a traumatic episode. Degeneration of the nucleus pulposus, the posterior longitudinal ligaments, and the annulus fibrosus may have taken place silently or have been manifest by mild, recurrent lumbar ache. A sneeze, lurch, or other trivial movement may then cause the nucleus pulposus to prolapse, pushing the frayed and weakened annulus posteriorly. A fragment of the nucleus protrudes through a tear in the annulus, usually to one side or the other (sometimes in the midline), where it impinges on a root or roots and cause the characteristic sciatic or other radicular pain and neurologic signs. In more severe cases of disc rupture, a small piece of the nucleus becomes entirely extruded as a “free fragment” and is mobile enough to affect a root at an adjacent level or to give rise to unusual positional features of radicular pain. Large protrusions cause pain by compressing the adjacent root against the articular apophysis or lamina. The protruded material may shrink, presumably from desiccation, but often there is continued chronic irritation of the root or later posterior osteophyte formation.