REIDER PART 2
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Frank M. Phillips Bruce Reider Vishal Mehta

Lumbar Spine

The examination of the lumbar spine may be seen as a continuation of the procedurę already dcscribed for the cervical and the thoracic spine; the lumbar spine can-not be evaluated in isolation. Abnormalities of the lumbar spine may lead to compensatory or secondary abnormalities in other portions of the spine or pelvis. Symptoms that appear to emanate from the lumbar region may actually be due to abnormalities of adjacent structures. The principles already enumerated for evalua-tion of the cervical and thoracic spine continue to be of value in the assessment of lumbar disorders.

Because disorders of the lumbar spine often produce pain in the pelvis, the hip, or the thigh, a thorough evalu-ation of the lumbar spine usually includes cxamination of these regions. The details of this portion of the examina-tion are outlined in Chapter 5, Pelvis, Hip, and Thigh, and are only alluded to here.

■ INSPECTION

Surface Anatomy and Alignment

POSTERIOR ASPECT

As with the rest of the spine, the dorsal location of the lumbar spine within the body makes the posterior view-point the most fruitful one for inspection (Fig. 9-1). When viewed from the posterior aspect, a longitudinal furrow is seen in most patients running down the midline from the thoracic spine to the sacrum. The spinous processes of the lumbar vertebrae run down the center of this furrow, and they are visible as a series of evenly placed bumps in thin individuals. Forward flcxion at the waist usually makes the tips of the spinous processes morę distinct and visible (Fig. 9-1C).

Paraspinous Muscles. On each side of the spinous processes runs a convex column of muscle. This contour is formed by the bulk of the paraspinous muscle mass. The morę supcrficial column of paraspinous muscles is collectively known as the erector spinae, or sacrospinalis. The erector spinae is split longitudinaUy into three components. From medial to lateral on each side, they are the rmiltifidus, the longissimus, and the ilio-costalis muscles. The individual contours of these muscles cannot be discerned because they lie deep to the lum-bodorsal fascia, and they are visualized as a group. The prominence due to the paraspinous muscles should be equal on both sides of the spine. In the prcsence of paraspinous muscle spasm, the contour of the muscles on one side of the spine may stand out in visibly greater prominence than those on the opposite side. Although almost any pa infuł lesion of the lumbar spine may cause paraspinous spasm, the most common cause of asym-metric spasm is paraspinous muscle strain.

Symmetry. As in the rest of the spine, the verification of symmetry is an important part of inspection of the lumbar spine. It should appear that a plumb linę suspended from the vertebra prominens at the base of the neck would bisect the lumbar spine and continue on through the center of the natal cleft between the buttocks. In addi-tion to looking for straightness of the lumbar spine itself, the examincr should carefully inspect and compare the spacc created between the upper limbs and the trunk as the hands hang loosely at the patients sides. Noting asymmetry of these spaces may allow the examiner to detect a subtle coronal deformity of the spine that would otherwise go undctected.

Pelvic Obliquity. The examiner should also verify that the patients pclvis is level. An imaginary linę drawn between the posterior superior iliac spines or the iliac crests should be parallel to the floor. If these landmarks are not clearly visible, the examincr may have to palpate the iliac crests to verify that they are equidistant from the floor. If a pelvic ob!iquity is found, it may be the result of a deformity within the spine, such as scoliosis or an anomalous vertebra, or it may be secondary to a leg length discrepancy. The possiblc causes of a leg length

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