|Spinal cord compression|
|Classification and external resources|
Spinal cord compression develops when the spinal cord is compressed by bone fragments from a vertebral fracture, a tumor, abscess, ruptured intervertebral disc or other lesion. It is regarded as a medical emergency independent of its cause, and requires swift diagnosis and treatment to prevent long-term disability due to irreversible spinal cord injury.
Symptoms suggestive of cord compression are back pain, a dermatome of increased sensation, paralysis of limbs below the level of compression, decreased sensation below the level of compression, urinary and fecal incontinence and/or urinary retention. Lhermitte's sign (intermittent shooting electrical sensation) and hyperreflexia may be present.
Diagnosis is by X-rays but preferably magnetic resonance imaging (MRI) of the whole spine. The most common causes of cord compression are tumors, but abscesses and granulomas (e.g. in tuberculosis) are equally capable of producing the syndrome. Tumors that commonly cause cord compression are lung cancer (non-small cell type), breast cancer, prostate cancer, renal cell carcinoma, thyroid cancer, lymphoma and multiple myeloma.
Surgery is indicated in localised compression as long as there is some hope of regaining function. It is also occasionally indicated in patients with little hope of regaining function but with uncontrolled pain. Postoperative radiation is delivered within 2-3 weeks of surgical decompression. Emergency radiation therapy (usually 20 Gray in 5 fractions or 30Gy in 10 fractions) is the mainstay of treatment for malignant spinal cord compression. It is very effective as pain control and local disease control. Some tumors are highly sensitive to chemotherapy (e.g. lymphomas, small-cell lung cancer) and may be treated with chemotherapy alone.
Once complete paralysis has been present for more than about 24 hours before treatment, the chances of useful recovery are greatly diminished, although slow recovery, sometimes months after radiotherapy, is well recognised.
The median survival of patients with metastatic spinal cord compression is about 12 weeks, reflecting the generally advanced nature of the underlying malignant disease.