REIDER PART 284

344_Chapter 9_Lumbar Spine

Figurę 9-11. Lumbar spine rotation.

Figurę 9-12. Palpation of the iliac crests.

interspinous ligaments. If the patient is standing, palpa-tion is most comfortably accomplished with the examiner in the seated position. For orientation, the examiner should identify the top of each iliac crest and draw an imaginary linę betwccn the two. This linę usually passes through the interspace betwccn the L4 and the L5 spinous processes (Fig. 9-12). The examiner can thcn identify the individual spinous processes by counting upward or downward from the L4-L5 interspace. Localized tender-ness at a particular level may indicate pathology at that levcl. Conditions that may cause tenderness localized to one levcl include sprains or disruptions of the posterior ligaments of the spine, fractures of the posterior ele-ments, and tumors of the posterior elements. In the pres-ence of degenerative arthritis, or spondylosis, tenderness over the posterior vertebrae is of uncertain significance. Marked superficial lumbar tenderness, especially in response to very light palpation, suggests the possibility of symptom magnification.

In the presence of spondylolisthesis, palpation of the spinous processes may help confirm the examincr s visual impression of a step-off above the involvcd vertebra. The amount of slippage usually must be at least 50% of the diameter of the lumbar vertebral bodies before the step-off can be detected by physical examination. Paraspinous Muscles. On each side of the spinous processes lie the muscular columns of the erector spinae, or sacrospinalis, composed of the multifidus, the longissimus, and the iliocostalis muscles. The indi-vidual components cannot normally be distinguished by palpation. In the presence of muscle spasm, the paraspinous muscle column may appear morę prominent and feel firmer than usual. Muscle spasm may reflect a local muscle injury or may be a response to a nearby loeus of pain within the spine itsclf. If muscle spasm is suspected, the patient should be asked to bend toward the involved side whilc the examiner continues to palpate the paraspinous muscle in question (see Fig. 9-10). Normally, the paraspinous muscles on the side to which the patient is bending should soften and relax. If they remain firm, the impression of spasm is confirmed. Unilateral muscle spasm may cause a list or reactive scoliosis; bilateral muscle spasm may result in the loss of the normal lumbar lordosis.

The examiner should also notę whether the paraspinous muscles are tender. Diffuse muscular tenderness may reflect a strain of the muscles being examined. Trigger pointSy tender nodules within the paraspinous muscles, should also be noled. Trigger points are freąuently a reac-tion to a painful stimulus to the paraspinous muscles. They may also indicate the presence of fibromyalgia.

Other Bony Structures. The posterior facet joints of the lumbar spine are located deep to the paraspinous muscles just lateral to the spinous processes. Localized tenderness over these joints may be caused by facet joint arthritis or a painful facet joint syndromc. Further