NEUROLOGY
BACK AND SPINAL CORD DISEASE
Differential diagnosis of back pain
• Musculoskeletal: musculoligamentous “strain” (experienced by up to 80% of population at some time), OA, RA, spondylolisthesis, vertebral fx, inflammatory spondyloarthritis (ankylosing spondylitis, reactive, psoriatic), myofascial pain syndrome
• Spinal cord (myelopathy)/nerve root (radiculopathy):
Degenerative/traumatic: disc herniation, spondylosis, vertebral fx and subluxation
Neoplastic: lung, breast, prostate, RCC, thyroid, colon, multiple myeloma, lymphoma
Infectious (also see ID section): osteomyelitis, epidural abscess, zoster, Lyme, CMV, HIV
• Referred pain from visceral disease: (quality of pain can be important to distinguish)
GI: PUD, cholelithiasis, pancreatitis, pancreatic cancer
GU: pyelonephritis, nephrolithiasis, uterine or ovarian cancer, salpingitis
Vascular: aortic dissection, leaking aortic aneurysm
Initial evaluation
• History: location, radiation, trauma, wt loss, cancer hx, fever, immunocompromised, neurologic symptoms, saddle anesthesia, incontinence, urinary retention, IV drug use
• General physical exam: local tenderness, ROM, signs of infection or malignancy,
signs of radiculopathy (experienced as sharp/lancinating pain radiating into limb):
Spurling sign (radicular pain w/ downward force to extended & ipsilaterally rotated head): 30% Se, 93% Sp
straight leg raise (radicular pain at 30–70°): ipsilateral: 92% Se, 28% Sp; crossed (contralateral leg raised): 28% Se, 90% Sp
• Neurologic exam: full motor (including sphincter tone), sensory (including perineal region) and reflexes including anal (S4) and cremasteric (L2)
• Laboratory (depending on suspicion): CBC, ESR, Ca, PO4, AФ, CSF
• Neuroimaging: low yield if nonradiating pain, high false 
rate (incidental spondylosis) depending on suspicion: X-rays, CT or CT myelography, MRI, bone scan
• EMG/NCS: may be useful to distinguish root/plexopathies from peripheral neuropathies
SPINAL CORD COMPRESSION
Clinical manifestations
• Acute: flaccid paraparesis and absent reflexes (“spinal shock”)
• Subacute–chronic: spastic paraparesis and hyperactive reflexes
• Posterior column dysfunction in legs (loss of vibratory sense or proprioception)
• Sensory loss below level of lesion
• Bilateral prominent Babinski responses ± ankle clonus
Evaluation & treatment
• Empiric spine immobilization (collar, board) for all trauma patients
• STAT MRI (at and above clinical spinal level, pre- and postgadolinium) or CT myelogram
• Emergent neurosurgical and/or neurology consultation
• Urgent radiation therapy ± surgery for compression if due to metastatic disease
• High-dose steroids depending on cause:
Tumor: dexamethasone 16 mg/d IV (usually 4 mg q6h) with slow taper over wks
Trauma: methylprednisolone 30 mg/kg IV over 15 min then 5.4 mg/kg/h × 24 h (if started w/in 3 h of injury) or × 48 h (if started 3–8 h after injury) ( JAMA 1997;277:1597)
NERVE ROOT COMPRESSION
Clinical manifestations
• Radicular pain aggravated by activity (esp. bending, straining, coughing), relieved by lying
• Sciatica = radicular pain radiating from buttocks down lateral aspect of leg, often to knee or lateral calf ± numbness and paresthesias radiating to lateral foot
Treatment of nerve root compression
• Conservative: avoid bending/lifting; NSAIDs; Rx neuropathic pain (see “Peripheral Neuropathies”); physical therapy
• Spinal epidural steroid injections (ESI): limited short-term relief of refractory radicular pain
• Surgery: cord compression or cauda equina syndrome; progressive motor dysfunction; bowel/bladder dysfunction; failure to respond to conservative Rx (NEJM 2007;356:2245)