DR. SCOTT COOK: What causes sciatica?
What causes sciatica?
The term sciatica describes the symptoms of leg pain and possibly tingling, numbness or weakness that originates in the lower back and travels through the buttock and down the large sciatic nerve in the back of the leg. Sciatica (pronounced sigh-at-ih-kah) is not a medical diagnosis in and of itself — it is a symptom of an underlying medical condition.
There are six lower back problems that are the most common causes of sciatica:
Lumbar herniated disc
A herniated disc occurs when the soft inner core of the disc (nucleus pulposus) leaks out, or herniates, through the fibrous outer core (annulus) and irritates the contiguous nerve root. A herniated disc is sometimes referred to as a slipped disc, ruptured disc, bulging disc, protruding disc, or a pinched nerve. Sciatica is the most common symptom of a lumbar herniated disc.
Degenerative disc disease
While disc degeneration is a natural process that occurs with aging, for some people one or more degenerated discs in the lower back can also irritate a nerve root and cause sciatica.
This condition occurs when a small stress fracture allows one vertebral body to slip forward on another (e.g. the L5 vertebra slips over the S1 vertebra).
Lumbar spinal stenosis
This condition commonly causes sciatica due to a narrowing of the spinal canal. Lumbar spinal stenosis is related to natural aging in the spine and is relatively common in adults over age 60.
The sciatic nerve can get irritated as it runs under the piriformis muscle in the buttocks. If the piriformis muscle irritates or pinches a nerve root that comprises the sciatic nerve, it can cause sciatica-type pain.
Sacroiliac joint dysfunction
Irritation of the sacroiliac joint — located at the bottom of the spine — can also irritate the L5 nerve, which lies on top of the sacroiliac joint, causing sciatica-type pain.
Other causes of Sciatica are pregnancy, scar tissue, spinal tumors and spinal infections.
Sciatica is often characterized by one or more of the following symptoms:
• Constant pain in only one side of the buttock or leg (rarely can occur in both legs)
• Pain that is worse when sitting
• Burning or tingling down the leg (vs. a dull ache)
• Weakness, numbness or difficulty moving the leg or foot
• A sharp pain that may make it difficult to stand up or to walk
The sciatica symptoms are different depending on where the nerve is pinched. For example, a lumbar segment 5 (L5) nerve impingement can cause weakness in extension of the big toe and potentially in the ankle. Sciatic pain can vary from infrequent and irritating to constant and incapacitating.
Specific sciatica symptoms also vary widely in type, location and severity, depending upon the condition causing the sciatica (such as a lumbar herniated disc). While symptoms can be very painful, it is rare that permanent sciatic nerve damage (tissue damage) will result.
Sciatica is typically very treatable through chiropractic care, which can allow you to begin living the life you deserve, pain free.