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HARRINGTON & SCHNEIDER
The pain and neurologic sequelae can dramatically affect patientsdparticularly the elderly, who might have marginal reserve to overcome such limitations in movement, strength, and sensation. It has been reported that neck and back pain are common in the elderly, with one study indicating a 15% 1-month prevalence rate for back pain and 11% for neck pain [55]. Pathophysiology Initially described by Parkinson in 1817, cervical radiculopathy identifies a constellation of signs and symptoms that are associated with altered function of cervical spine nerve roots. This may manifest itself as pain in the neck region as well as discomfort in a radicular distribution in one or both upper extremities. Additionally, the pain can occur in combination with sensory, motor, or reflex changes [56]. Although there are a number of disease processes that might affect the cervical spine and exiting nerve roots (vertebral fracture or dislocation, compression by tumor or abscess, vertebral collapse, spondylolisthesis, and trauma to cervical roots), cervical disc herniation and cervical spondylosis are the most common etiologies causing radicular symptoms of the upper extremities [57]. A 1969 study reported that 97% of patients with radiculopathy had radiographic evidence of foraminal stenosis [58]. Age-related alterations in the chemical structure of the nucleus pulposis and annulus fibrosus result in a disturbance of the normal architecture of the cervical spine. Specifically, there is a loss of height between the vertebral bodies as the discs bulge posteriorly into the spinal canal. As the vertebral bodies become closer to each other, there is infolding of the ligamentum flavum and facet joint capsule. The formation of osteophytes as part of a normal aging process, in combination with the posteriorly protruded disc material and redundant soft tissue, results in a reduction in the spinal canal and foraminal dimensions. This, in turn, may result in extrinsic compression of the nerve root or spinal cord [59]. The nerve roots of the cervical spine exit at nearly a horizontal orientation, in close proximity to the bone and discdfactors that are critical to the pathogenesis of nerve root compression and radiculopathy [57]. Specifically, the boundaries of the neuroforaminae include the uncovertebral joint anteromedially, facet joints, and articular processes posterolaterally, and pedicles of superior and inferior bodies both superiorly and inferiorly. Although cervical radiculopathy is the most common reason for atraumatic limb pain, the clinician must remember to consider other etiologies for the upper extremity pain, weakness, or sensory deficits. Peripheral nerves are prone to compression and subsequent irritation at many points along their route from the spinal cord to the hand. Bony prominences, tendon sheaths, muscles, and vascular structures can all provide a substrate for nerve impingement and dysfunction. Although not discussed in detail here, carpel tunnel syndrome, pronator syndrome, and thoracic outlet syndrome are all examples of such disease entities [57,60,61].