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Patient Education: Diseases Conditions Treatments & Procedures

Disc Herniation


Leg pain is often caused by pressure on a nerve. The most common cause of an acute leg pain is disc herniation. Discs are the cushions between the vertebrae and are made up of an outer envelope of fibrous tissue (annulus fibrosis) and an inner gelatin like substance (nucleus pulposis). As we get older, unfortunately, the inner gelatin loses its water and gets stiffer, while the outer fibrous envelope also ages and can develop small fissures. A sudden back strain can "pop" that disc or it may occur without any event. CT scans or MRI is useful for diagnosis of disc herniation. There is good news for you if you do develop a disc hedrniation. Eighty-five per cent of all disc herniations resolve in that the pain of nerve root compression improves without any intervention. The disc does not "go back in", but may shrink in time. As long as there is no increasing weakness in your leg or foot and there is no problem with your bowel or bladder, then it is best to wait 6 weeks before thinking about surgery for your disc herniation. Once resolved, we recommend going back to your normal routine and no restrictions are necessary; but please always lift with your knees bent and any weight close to your body.
Indications for Surgery

The decision to operate on sciatica must respect two opposing needs:

  1. to avoid a too protracted conservative treatment that may lengthen the time off from work and reduce the chances of a successful surgical treatment, and
  2. to avoid surgery in patients with a herniated disc that may become asymptomatic.

The indication for surgery may be absolute or relative. An absolute indication for surgery is when there is bowel or bladder dysfunction, (cauda equina syndrome). Otherwise, surgery is performed electively when leg symptoms are not improving by 6 weeks to 3 months and quality of life is impacted. The presence of spinal stenosis or foraminal stenosis will also favour operative management. In general, patients with exclusively leg pain do better with surgery than those with a large component of back pain.

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