Chapter 016. Back and Neck Pain (Part 13) Chronic Low Back Pain CLBP, defined as pain lasting >12 weeks, accounts for 50% of total back pain costs. Risk factors include obesity, female gender, older age, prior history of back pain, restricted spinal mobility, pain radiating into a leg, high levels of psychological distress, poor self-rated health, minimal physical activity, smoking, job dissatisfaction, and widespread pain. Combinations of these premorbid factors have been used to predict which individuals with ALBP are likely to develop CLBP. The initial approach to these patients is similar to that for ALBP. Treatment of this heterogeneous group of patients is directed toward the underlying cause when known; the ultimate goal is to restore function to the maximum extent possible. Many conditions that produce CLBP can be identified by a combination of neuroimaging and electrophysiologic studies. Spine MRI and CT-myelography are almost always the imaging techniques of choice. Imaging studies should be performed only in circumstances when the results are likely to influence management. Injection studies can be used diagnostically to help determine the anatomic source of back pain. Reproduction of the patient's typical pain with diskography has been used as evidence that a specific disk is the pain generator. Pain relief following a foraminal nerve root block or glucocorticoid injection into a facet has been similarly used as evidence that the facet joint or nerve root is the source. However, the possibility that the injection response was a placebo effect or due to systemic absorption of the glucocorticoids is usually not considered. The value of these procedures in the treatment of CLBP or in the selection of candidates for surgery is largely unknown despite their widespread use. The value of thermography in the assessment of radiculopathy also has not been rigorously studied. The diagnosis of nerve root injury is most secure when the history, examination, results of imaging studies, and the EMG are concordant. The correlation between CT and EMG for localization of nerve root injury is between 65 and 73%. Up to one-third of asymptomatic adults have a disk protrusion detected by CT or MRI scans. Thus, surgical intervention based solely upon radiologic findings increases the likelihood of an unsuccessful outcome. An unblinded study in patients with chronic sciatica found that surgery could hasten relief of symptoms by ~2 months; however, at 1 year there was no advantage of surgery over conservative medical therapy, and nearly all patients (95%) in both groups made a full recovery regardless of the treatment approach. CLBP can be treated with a variety of conservative measures. Acute and subacute exacerbations are managed with NSAIDs and comfort measures. There is no good evidence to suggest that one NSAID is more effective than another. Bed rest should not exceed 2 days. Activity tolerance is the primary goal, while pain relief is secondary. Exercise programs can reverse atrophy in paraspinal muscles and strengthen extensors of the trunk. Intensive physical exercise or "work hardening" regimens (under the guidance of a physical therapist) have been effective in returning some patients to work, improving walking distances, and diminishing pain. The benefit can be sustained with home exercise regimens. It is difficult to endorse one specific exercise or PT regimen given the heterogeneous nature of this patient group. The role of manipulation, back school, or epidural steroid injections in the treatment of CLBP is unproven. There is no strong evidence to support the use of acupuncture or traction. A reduction in sick leave days, long-term health care utilization, and pension expenditures may offset the initial expense of multidisciplinary treatment programs. Studies of hydrotherapy for CLBP have yielded mixed results; however, given its low risk and cost, hydrotherapy can be considered as a treatment option. Transcutaneous electrical nerve stimulation (TENS) has not been adequately studied in CLBP. Pain in the Neck and Shoulder Table 16-4 Cervical Radiculopathy—Neurologic Features Examination Findings Cervica l Nerve Roots Reflex Sensor y Motor Pain Distribution C5 Biceps Over lateral deltoid Supraspinatus a (initial arm abduction) Infraspinatus a (arm external rotation) Deltoid a (arm abduction) Biceps (arm Lateral arm, medial scapula flexion) C6 Biceps Thumb, index fingers Radial hand/forearm Biceps (arm flexion) Pronator teres (internal forearm rotation) Lateral forearm, thumb, index finger C7 Tricep s Middle fingers Dors um forearm Triceps a (arm extension) Wrist extensors a Extensor digitorum a (finger extension) Posterio r arm, dorsal forearm, lateral hand C8 Finger flexors Little finger Medial Abductor pollicis brevis (abduction D1) 4th and 5th fingers, medial forearm hand and forearm First dorsal interosseous (abduction D2) Abductor digiti minimi (abduction D5) T1 Finger flexors Axilla and medial arm Abductor pollicis brevis (abduction D1) First dorsal interosseous (abduction D2) Abductor digiti minimi (abduction D5) Medial arm, axilla a These muscles receive the majority of innervation from this root. Neck pain, which usually arises from diseases of the cervical spine and soft tissues of the neck, is common (4.6% of adults in one study). Neck pain arising from the cervical spine is typically precipitated by movement and may be accompanied by focal tenderness and limitation of motion. Pain arising from the brachial plexus, shoulder, or peripheral nerves can be confused with cervical spine disease, but the history and examination usually identify a more distal origin for the pain. Cervical spine trauma, disk disease, or spondylosis may be asymptomatic or painful and can produce a myelopathy, radiculopathy, or both. The nerve roots most commonly affected are C7 and C6. . Chapter 016. Back and Neck Pain (Part 13) Chronic Low Back Pain CLBP, defined as pain lasting >12 weeks, accounts for 50% of total back pain costs. Risk factors. innervation from this root. Neck pain, which usually arises from diseases of the cervical spine and soft tissues of the neck, is common (4.6% of adults in one study). Neck pain arising from the. the anatomic source of back pain. Reproduction of the patient's typical pain with diskography has been used as evidence that a specific disk is the pain generator. Pain relief following