Symptoms and Signs

Sensory symptoms often include paresthesias; may begin in one or both feet and ascend. Sensory level to pin sensation or vibration often correlates well with location of transverse lesions. May have isolated pain/temperature sensation loss over the shoulders (“cape” or “syringomyelic” pattern) or loss of sensation to vibration/position sense on one side of the body and pain/temperature loss on the other (Brown-Séquard hemicord syndrome).

Motor symptoms are caused by disruption of corticospinal tracts that leads to quadriplegia or paraplegia with increased muscle tone, hyperactive deep tendon reflexes, and extensor plantar responses. With acute severe lesions, there may be initial flaccidity and areflexia (spinal shock).

Autonomic dysfunction includes primarily urinary retention; should raise suspicion of spinal cord disease when associated with back or neck pain, weakness, and/or a sensory level.

Interscapular pain may be first sign of midthoracic cord compression; radicular pain may mark site of more laterally placed spinal lesion; pain from lower cord (conus medullaris) lesion may be referred to low back.

Specific Signs By Spinal Cord Level

Approximate indicators of level of lesion include the location of a sensory level, a band of hyperalgesia/hyperpathia at the upper end of the sensory disturbance, isolated atrophy or fasciculations, or lost tendon reflex at a specific spinal cord segment.

Intramedullary and Extramedullary Syndromes

Spinal cord disorders may be intramedullary (arising from within the substance of the cord) or extramedullary (compressing the cord or its blood supply). Extramedullary lesions often produce radicular pain, early motor signs, and sacral sensory loss. Intramedullary lesions produce poorly localized burning pain, less prominent motor signs, and often spare perineal/sacral sensation.

Acute and Subacute Spinal Cord Diseases

(See Chap. 22 Spinal Cord Compression)

Neoplastic spinal cord compression (Chap. 22 Spinal Cord Compression): Most are epidural in origin, resulting from metastases to the adjacent spinal bones (Fig. 191-2. Epidural Spinal Cord Compression due to Breast Carcinoma). Almost any tumor can be responsible: breast, lung, prostate, kidney, lymphoma, and myeloma most frequent. Thoracic cord most commonly involved. Initial symptom is usually back pain, worse when recumbent, with local tenderness preceding other symptoms by many weeks. Spinal cord compression due to metastases is a medical emergency; in general, therapy will not reverse paralysis of >48 h duration.

Spinal epidural abscess: Triad of fever, localized midline dorsal spine or neck pain, and progressive limb weakness; once neurologic signs appear, cord compression rapidly progresses.

Spinal epidural hematoma: Presents as acute focal or radicular pain followed by variable signs of a spinal cord or conus medullaris disorder.

Acute disk herniation: Cervical and thoracic disk herniations are less common than lumbar.

Spinal cord infarction: Anterior spinal artery infarction produces paraplegia or quadriplegia, sensory loss affecting pain/temperature but sparing vibration/position sensation (supplied by posterior spinal arteries), and loss of sphincter control. Onset sudden or progressive, evolving over minutes or a few hours. Associated conditions: aortic atherosclerosis, dissecting aortic aneurysm, vertebral artery occlusion or dissection in the neck, aortic surgery, or profound hypotension. Therapy is directed at the predisposing condition. When due to thromboembolism, acute anticoagulation is not indicated, with the possible exception of the unusual transient ischemic attack or incomplete infarction with a stuttering or progressive course.

Immune-mediated myelopathies: Acute transverse myelopathy (ATM) occurs in 1% of pts with SLE; associated with antiphospholipid antibodies. Sjögren's and Behçet's syndromes, mixed connective tissue disease, and p-ANCA vasculitis are other causes. Sarcoid can produce ATM with large edematous swelling of the spinal cord. Demyelinating diseases, either neuromyelitis optica (NMO) or multiple sclerosis (MS), also can present as ATM; glucocorticoids, consisting of IV methylprednisolone followed by oral prednisone, are indicated for moderate to severe symptoms and refractory cases may respond to plasma exchange (Chaps. 192 Multiple Sclerosis and 193 Neuromyelitis Optica). Treatment with mycophenolate mofetil or rituximab may protect against relapses in NMO. Other cases of ATM are idiopathic.

Infectious myelopathies: Herpes zoster is the most common viral agent, but herpes simplex virus types 1 and 2, EBV, CMV, rabies virus, and Zika virus are also well described; in cases of suspected viral myelitis, antivirals may be appropriately started pending laboratory confirmation. A number of enteroviruses and flaviviruses (e.g., Japanese encephalitis and West Nile virus) can cause a polio-like syndrome. Bacterial and mycobacterial causes are less common. Schistosomiasis is an important cause worldwide.

Chronic Myelopathies

Spondylitic myelopathies: One of the most common causes of gait difficulty in the elderly. Presents as neck and shoulder pain with stiffness, radicular arm pain, and progressive spastic paraparesis with paresthesias and loss of vibration sense; in advanced cases, urinary incontinence may occur. A tendon reflex in the arms is often diminished at some level. Diagnosis is best made by MRI. Treatment is surgical (Chap. 50 Back and Neck Pain).

Vascular malformations: An important treatable cause of progressive or episodic myelopathy. May occur at any level; diagnosis is often suggested by contrast-enhanced MRI (Fig. 191-3. Arteriovenous Malformation), but is confirmed by selective spinal angiography. Treatment generally consists of microsurgical resection, endovascular embolization of the major feeding vessels, or a combination of the two approaches.

Retrovirus-associated myelopathies: Infection with human T-cell lymphotropic virus I (HTLV-I) may produce a slowly progressive spastic paraparesis with variable pain, sensory loss, and bladder disturbance; diagnosis is made by demonstration of specific serum antibody. Treatment is symptomatic. A progressive vacuolar myelopathy may also result from HIV infection.

Syringomyelia: Cavitary expansion of the spinal cord resulting in progressive myelopathy; may be an isolated finding or associated with protrusion of cerebellar tonsils into cervical spinal canal (Chiari type 1). Classic presentation is loss of pain/temperature sensation in the neck, shoulders, forearms, or hands with areflexic weakness in the upper limbs and progressive spastic paraparesis; cough headache, facial numbness, or thoracic kyphoscoliosis may occur. Diagnosis is by MRI; treatment is surgical and often unsatisfactory.

Multiple sclerosis: Spinal cord involvement is common and is a major cause of disability especially in progressive forms of MS (Chap. 192 Multiple Sclerosis).

Subacute combined degeneration (vitamin B₁₂deficiency): Paresthesias in hands and feet, early loss of vibration/position sense, progressive spastic/ataxic weakness, and areflexia due to associated peripheral neuropathy; mental changes and optic atrophy may be present along with a serum macrocytic anemia. Causes include dietary deficiency especially in vegans, and gastric malabsorption syndromes including pernicious anemia. Diagnosis is confirmed by a low serum B₁₂ level, elevated levels of homocysteine and methylmalonic acid. Treatment is vitamin replacement beginning with 1 mg of IM vitamin B₁₂ repeated at regular intervals or by subsequent oral treatment.

Hypocupric myelopathy: Clinically nearly identical to subacute combined degeneration (above) except there is no neuropathy. Low levels of serum copper and usually ceruloplasmin make the diagnosis. Some cases are idiopathic and others follow GI procedures that hinder absorption; excess zinc ingestion is another cause. Treatment is oral copper supplementation.

Tabes dorsalis (tertiary syphilis): May present as lancinating pains, gait ataxia, bladder disturbances, and visceral crises. Cardinal signs are areflexia in the legs, impaired vibration/position sense, Romberg sign, and Argyll Robertson pupils which fail to constrict to light but accommodate.

Hereditary spastic paraplegia: Progressive spasticity and weakness in the legs occurring on a familial basis; may be autosomal dominant, recessive, or X-linked. More than 60 different loci identified.

Adrenomyeloneuropathy: X-linked disorder that is a variant of adrenoleukodystrophy. Usually, affected males have a history of adrenal insufficiency and then develop a progressive spastic paraparesis. Female heterozygotes may develop a slower progressive myelopathy without adrenal insufficiency. Diagnosis made by elevated very long chain fatty acids in plasma and in cultured fibroblasts. Allogeneic bone marrow transplantation has been successful in slowing progression of cognitive decline in ALD, but appears to be ineffective for the myelopathy. Nutritional supplements (Lorenzo's oil) have also been attempted without evidence of efficacy.

Complications

Bladder dysfunction with risk of urinary tract infection; bowel dysmotility; pressure sores; in high cervical cord lesions, mechanical respiratory failure; paroxysmal hypertension or hypotension with volume changes; severe hypertension and bradycardia in response to noxious stimuli or bladder or bowel distention; venous thrombosis and pulmonary embolism.