Sciatica

Article written by Michael D Burdi, MD

Sciatica is a general term used to describe a radiating pain down the buttock, thigh, and/or leg. Similar terms used to describe this symptom include lumbar radiculopathy and radiculitis. Other sensations associated with sciatica include numbness, burning, "pins and needles", and weakness in the leg. It is most frequently seen during middle age, but can be found in any age group.

There are a variety of factors that may cause sciatica; all of which have the common characteristic of irritating a nerve root in the low back. These nerves eventually form the sciatic nerve, which travels down the buttock and posterior thigh. The most common nerve cause of nerve irritation is bulging or herniation of an intervertebral disc, although other causes include arthritic conditions of the spine.

As one ages, the discs are subjected to wear and tear and the disk’s outer layer or annulus may weaken causing it to bulge .The annulus may also rupture, allowing the inner gel-like nucleus to extrude. Both of these situations can cause excessive pressure on the nerve roots passing through the lumbar spine. This pressure can irritate the nerve causing the symptoms known as sciatica. Furthermore, chemical factors released by the ’leaking’ disc have also been shown to irritate the nerve roots.

Those who experience sciatica should seek medical attention. A physical exam can help pinpoint the suspected area of nerve irritation. An MRI (magnetic resonance imaging) may be ordered by your physician to confirm the source of nerve irritation. The good news is that sciatica often improves with time. Initial treatment involves rest, non-steroidal anti-inflammatories, muscle relaxants, oral steroids, and other pain medications. Cortisone injections (Epidural injections) around the irritated nerve or nerves can be used in patients who do not respond to these first lines of treatment. Surgery is usually reserved for those who do not gain satisfactory relief in a reasonable period of time, usually 6 weeks to 3 months, or in those with significant worsening symptoms.

A rare, yet emergent situation, known as cauda equina syndrome arises if a disc herniation compresses the nerves controlling bladder and bowel function leading to loss of bladder/bowel control and decreased sensation in the genital area. This requires urgent medical and surgical attention.

Surgery for sciatica is aimed at relieving the source of compression on the nerve root. In most cases this involves removing the herniated portion of the disk pressing on the nerve root. This is known as a laminotomy and microdiscectomy. In some cases, decompressing or widening the "foramen" or hole through which the nerve root(s) passes out of the spine is necessary to relieve the pressure on it. This is known as a foraminotomy. After surgery your doctor may limit your lifting, bending and twisting for several weeks in order to reduce the chance of reherniation of the disc material, which occurs in 3-5% of patients undergoing a microdiscectomy.

In conclusion, patients experiencing sciatica should seek medical attention but in many cases can expect to improve in time with non-operative treatment modalities.