-IBIS-1.5.0-
tx
musculoskeletal system
intervertebral disc disease
diagnoses

definition and etiology

definition:
Rupture of the annulus fibrosus causing leaking of the nucleus pulposus into the intradural space. Also called "herniated disc", "herniated nucleus pulposus", "ruptured disc" or "disk syndrome".

etiology:
The cause is degeneration of the fibers of the annulus fibrosus, or trauma of the area leading to the rupture of the annulus. Rupture usually occurs at middle age or older. Then, the normal pressure that exists in the spine forces the nucleus pulposus through the rupture, which typically occurs in the posterior or posterolateral aspect of the disk. The most frequently affected disks are between the 4th lumbar and 5th lumbar and between the 5th lumbar and the first sacral vertebrae: the other lumbar disks rupture less commonly. The thoracics are rarely affected, but herniation also occurs between the 5th and 6th cervical and 6th and 7th cervical vertebrae. Symptoms of the rupture occur when the nucleus pulposus compresses a nerve root, usually unilaterally, but bilateral compression may result if the lesion was large enough.

signs and symptoms

signs and symptoms:
• History of trauma, or of lifting a heavy object or particularly of a lift and twist maneuver. In some cases, however, no such history is elicited.
• Sudden pain, may often be severe and debilitating.
• Pain is worse movement, flexion of the trunk or hip, sneezing/coughing/straining at stool (Valsalva).
• Radicular pain, paresthesias, decreased DTRs.
• Muscles innervated by the compressed nerve may fasciculate, become weak and atrophy, twitch, or spasm.
• (+) straight leg raise, and other musculoskeletal confirming tests.
• Urine retention or incontinence from loss of bladder control: this is a medical emergency.

lab findings:
• (+) CT scan, x-rays, myelography, MRI (now the procedure of choice).

course and prognosis

Prognosis is good with proper treatment. Recurrence is possible if the patient is not instructed how to prevent similar future injury (lift with knees bent, not back; don't lift and twist).

differential diagnosis

• Strain/sprain.
• Facet syndrome.
• Degenerative joint disease
• Extramedullary spinal tumor: meningioma or neurofibroma or the nerve root itself.
• Carcinoma.
• Spondylosis.
• Spondylolisthesis.


footnotes