Chapter 016. Back and Neck Pain (Part 9)

Neoplasms(See also Chap. 374) Back pain is the most common neurologic symptom in patients with systemic cancer and may be the presenting symptom. The cause is usually vertebral metastases. Metastatic carcinoma (breast, lung, prostate, thyroid, kidney, gastrointestinal tract), multiple myeloma, and non-Hodgkins and Hodgkins lymphomas frequently involve the spine. Cancer-related back pain tends to be constant, dull, unrelieved by rest, and worse at night. By contrast, mechanical low back pain usually improves with rest. Plain x-rays may or may not show destructive lesions in one or several vertebral bodies without disk space involvement. MRI, CT, and CT-myelography are the...
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Chapter 016. Back and Neck Pain (Part 9) Chapter 016. Back and Neck Pain (Part 9) Neoplasms (See also Chap. 374) Back pain is the most common neurologic symptomin patients with systemic cancer and may be the presenting symptom. The cause isusually vertebral metastases. Metastatic carcinoma (breast, lung, prostate, thyroid,kidney, gastrointestinal tract), multiple myeloma, and non-Hodgkins andHodgkins lymphomas frequently involve the spine. Cancer-related back paintends to be constant, dull, unrelieved by rest, and worse at night. By contrast,mechanical low back pain usually improves with rest. Plain x-rays may or may notshow destructive lesions in one or several vertebral bodies without disk spaceinvolvement. MRI, CT, and CT-myelography are the studies of choice when spinalmetastasis is suspected. MRI is preferred, but the most rapidly available procedureis best because the patients condition may worsen quickly. Fewer than 5% ofpatients who are nonambulatory at the time of diagnosis ever regain the ability towalk, thus early diagnosis is crucial. Infections/Inflammation Vertebral osteomyelitis is usually caused by staphylococci, but otherbacteria or tuberculosis (Potts disease) may be responsible. The primary source ofinfection is usually the urinary tract, skin, or lungs. Intravenous drug use is a well-recognized risk factor. Whenever pyogenic osteomyelitis is found, the possibilityof bacterial endocarditis should be considered. Back pain exacerbated by motionand unrelieved by rest, spine tenderness over the involved spine segment, and anelevated ESR are the most common findings in vertebral osteomyelitis. Fever oran elevated white blood cell count is found in a minority of patients. Plainradiographs may show a narrowed disk space with erosion of adjacent vertebrae;however, these diagnostic changes may take weeks or months to appear. MRI andCT are sensitive and specific for osteomyelitis; CT may be more readily availablein emergency settings and better tolerated by some patients with severe back pain. Spinal epidural abscess (Chap. 372) presents with back pain (aggravated bymovement or palpation) and fever. Signs of nerve root injury or spinal cordcompression may be present. The abscess may track over multiple spinal levelsand is best delineated by spine MRI. Lumbar adhesive arachnoiditis with radiculopathy is due to fibrosisfollowing inflammation within the subarachnoid space. The fibrosis results innerve root adhesions, and presents as back and leg pain associated with motor,sensory, or reflex changes. Causes of arachnoiditis include multiple lumbaroperations, chronic spinal infections, spinal cord injury, intrathecal hemorrhage,myelography (rare), intrathecal injection of glucocorticoids or anesthetics, andforeign bodies. The MRI shows clumped nerve roots located centrally or adherentto the dura peripherally, or loculations of cerebrospinal fluid within the thecal sac.Clumped nerve roots may also occur with demyelinating polyneuropathy orneoplastic infiltration. Treatment is usually unsatisfactory. Microsurgical lysis ofadhesions, dorsal rhizotomy, and dorsal root ganglionectomy have been tried, butoutcomes have been poor. Dorsal column stimulation for pain relief has producedvarying results. Epidural injections of glucocorticoids have been of limited value. Metabolic Causes Osteoporosis and Osteosclerosis Immobilization or underlying conditions such as osteomalacia,hyperparathyroidism, hyperthyroidism, multiple myeloma, metastatic carcinoma,or glucocorticoid use may accelerate osteoporosis and weaken the vertebral body,leading to compression fractures and pain. The most common causes ofnontraumatic vertebral body fractures are postmenopausal (type 1) or senile (type2) osteoporosis (Chap. 348). Compression fractures occur in up to half of patientswith severe osteoporosis, and those who sustain a fracture have a 4.5-foldincreased risk for recurrence. The sole manifestation of a compression fracturemay be localized back pain or radicular pain exacerbated by movement and oftenreproduced by palpation over the spinous process of the affected vertebra. Theclinical context, neurologic signs, and x-ray appearance of the spine establish thediagnosis. Antiresorptive drugs including bisphosphonates (e.g., alendronate),transdermal estrogen, and tamoxifen have been shown to reduce the risk ofosteoporotic fractures. Fewer than one-third of patients with prior compressionfractures are adequately treated for osteoporosis despite the increased risk forfuture fractures; rates of primary prevention among individuals at risk, but withouta history of fracture, are even less. Compression fractures above the midthoracicregion s ...