Chapter 016. Back and Neck Pain (Part 8)

Degenerative ConditionsLumbar spinal stenosis describes a narrowed lumbar spinal canal. Neurogenic claudication is the usual symptom, consisting of back and buttock or leg pain induced by walking or standing and relieved by sitting. Symptoms in the legs are usually bilateral. Lumbar stenosis, by itself, is frequently asymptomatic, and the correlation between the severity of symptoms and degree of stenosis of the spinal canal is poor. Unlike vascular claudication, symptoms are often provoked by standing without walking. Unlike lumbar disk disease, symptoms are usually relieved by sitting. Focal weakness, sensory loss, or reflex changes may occur when spinal stenosis is...
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Chapter 016. Back and Neck Pain (Part 8) Chapter 016. Back and Neck Pain (Part 8) Degenerative Conditions Lumbar spinal stenosis describes a narrowed lumbar spinal canal.Neurogenic claudication is the usual symptom, consisting of back and buttock orleg pain induced by walking or standing and relieved by sitting. Symptoms in thelegs are usually bilateral. Lumbar stenosis, by itself, is frequently asymptomatic,and the correlation between the severity of symptoms and degree of stenosis of thespinal canal is poor. Unlike vascular claudication, symptoms are often provokedby standing without walking. Unlike lumbar disk disease, symptoms are usuallyrelieved by sitting. Focal weakness, sensory loss, or reflex changes may occurwhen spinal stenosis is associated with radiculopathy. Severe neurologic deficits,including paralysis and urinary incontinence, occur rarely. Spinal stenosis can beacquired (75%), congenital, or due to a combination of these factors. Congenitalforms (achondroplasia, idiopathic) are characterized by short, thick pedicles thatproduce both spinal canal and lateral recess stenosis. Acquired factors thatcontribute to spinal stenosis include degenerative diseases (spondylosis,spondylolisthesis, scoliosis), trauma, spine surgery, metabolic or endocrinedisorders (epidural lipomatosis, osteoporosis, acromegaly, renal osteodystrophy,hypoparathyroidism), and Pagets disease. MRI provides the best definition of theabnormal anatomy (Fig. 16-5). Figure 16-5 Spinal stenosis. Sagittal T2 fast spin echo magnetic resonance imaging of anormal (left) and stenotic (right) lumbar spine, revealing multifocal narrowing(arrows) of the cerebrospinal fluid spaces surrounding the nerve roots within thethecal sac. Conservative treatment of symptomatic spinal stenosis includesnonsteroidal anti-inflammatory drugs (NSAIDs), exercise programs, andsymptomatic treatment of acute pain episodes. Surgical therapy is consideredwhen medical therapy does not relieve symptoms sufficiently to allow foractivities of daily living or when significant focal neurologic signs are present.Most patients with neurogenic claudication treated surgically experience at least75% relief of back and leg pain. Up to 25% develop recurrent stenosis at the samespinal level or an adjacent level 5 years after the initial surgery; recurrentsymptoms usually respond to a second surgical decompression. Facet joint hypertrophy can produce unilateral radicular symptoms or signsdue to bony compression; symptoms are often indistinguishable from disk-relatedradiculopathy. Stretch signs, focal motor weakness, hyporeflexia, or dermatomalsensory loss may be present. Hypertrophic superior or inferior facets can bevisualized by x-rays, CT, or MRI. Surgical foraminotomy results in long-termrelief of leg and back pain in 80–90% of these patients. The usefulness oftherapeutic facet joint blocks for pain has not been rigorously studied. Arthritis Spondylosis, or osteoarthritic spine disease, typically occurs in later life andprimarily involves the cervical and lumbosacral spine. Patients often complain ofback pain that is increased with movement and associated with stiffness. Therelationship between clinical symptoms and radiologic findings is usually notstraightforward. Pain may be prominent when x-ray, CT, or MRI findings areminimal, and large osteophytes can be seen in asymptomatic patients.Radiculopathy occurs when hypertrophied facets and osteophytes compress nerveroots in the lateral recess or intervertebral foramen. Osteophytes arising from thevertebral body may cause or contribute to central spinal canal stenosis. Discdegeneration may also play a role in reducing the cross-sectional area of theintervertebral foramen; the descending pedicle may compress the exiting nerveroot. Rarely, osteoarthritic changes in the lumbar spine are sufficient to compressthe cauda equina. Ankylosing Spondylitis (See also Chap. 318) This distinctive arthritic spine disease typicallypresents with the insidious onset of low back and buttock pain. Patients are oftenmales below age 40. Associated features include morning back stiffness, nocturnalpain, pain unrelieved by rest, an elevated ESR, and the histocompatibility antigenHLA-B27. Onset at a young age and back pain improving with exercise arecharacteristic. Loss of the normal lumbar lordosis and exaggeration of thoracickyphosis develop as the disease progresses. Inflammation and erosion of the outerfibers of the annulus fibrosus at the point of contact with the vertebral body arefollowed by ossification and bony growth that bridges adjacent vertebral bodiesand reduces spine mobility in all planes. Radiologic hallmarks are periarticulardestru ...