Sciatica (neuralgia)
La sciatic neuralgia, commonly known as sciatica, is a sharp pain felt along one of the 2 sciatic nerves. Located at the back of each of the legs, they are the largest nerves in the body (see diagram). They join the spine at the lower back, at the level of the lumbar and sacral vertebrae (just above the coccyx).
The pain mainly affects the buttock and the thigh, and often extends to the foot. Most often, the pain affects only one side of the body.
Sciatica, low back pain or herniated disc? In the case of low back pain, “backache” or “lumbago”, the pain is usually localized to the lower back and buttocks. It is variable in intensity and may or may not limit movement. If you have a sciatica, pain is usually felt on one side of the body, in a buttock and all the way down one leg to the foot; sometimes also in the lower back. A herniated disc is an abnormal protrusion of part of an intervertebral disc in the spine. It is one of the main causes of low back pain or sciatica. |
Causes
La sciatica is not a disease in itself. It is the sign that the sciatic nerve is irritated. The majority of cases are attributable to herniated disc, which compresses one or the other of the 5 roots of the sciatic nerve. Symptoms vary slightly, depending on the affected root. (The root is the part of the nerve that joins the spinal cord inside the spine.)
Sciatica can also be caused by any of the following factors.
- Narrow lumbar canal (spinal canal stenosis). A narrowing of the canal (in which the nerves are inserted) can cause compression of the nerve roots in the region of the lumbar vertebrae, and sciatica. This mainly occurs in older people.
- Piriforme syndrome. It is caused by inflammation of a muscle in the pelvis called the piriformis (pear-shaped) or pyramidal muscle. If this muscle is contracted and swollen, it can put pressure on the sciatic nerve and irritate it. Athletes and people who train inadequately are more prone to it.
- Facet syndrome. This syndrome originates in the facet joints, thin joints located at the top and bottom of each vertebra (not to be confused with the intervertebral discs, another structure that allows the articulation of the vertebrae). Poor posture or movement can create a slight misalignment of these facets. Back pain and sometimes sciatica can follow.
- Trauma. A fall, car accident, or any other situation that results in a blow to the back can cause damage to the nerve roots.
- Other causes. Osteoarthritis or metastases that put pressure on the sciatic nerve can cause back pain and, more rarely, sciatica. These two situations occur mainly in the elderly.
Evolution
In the majority of people with sciatic neuralgia, symptoms resolve within 4 weeks. However, it often tends to reappear if nothing is done to prevent it. Sciatica can also be associated with a problem with chronic low back pain.
When to consult?
When symptoms resembling those of sciatica develop, it is best to see a doctor for an precise diagnosis.
If it is sciatica and treatments fail to relieve the pain or the pain gets worse, see a doctor again.
See a doctor emergency if :
- the back pain is intense to the point of being hardly bearable;
- symptoms of sciatica are accompanied by urinary or fecal incontinence (or on the contrary, retention), impotence, loss of feeling in the perineum area and inside the thighs or difficulty in standing standing or climbing stairs;
- in addition to the symptoms of sciatica, rapid and unexplained weight loss occurs.