Sciatica is a type of pain that affects the sciatic nerve, which is the longest and thickest nerve in the body. It starts in the buttock/gluteal area and extends to the hips, buttocks, and leg, ending just below the knee. The sciatic nerve is made up of five nerve roots, two from the lumbar spine and three from the sacrum, which come together to form the right and left sciatic nerves. The sciatic nerve then branches into other nerves that continue down the leg and into the foot and toes.
The most common cause of sciatica is a herniated disk or bone spur that puts pressure on the nerve, causing inflammation, pain, and sometimes numbness in the affected leg.
Although sciatica can cause severe pain, most cases can be treated and resolved within a few weeks. In some cases, however, such as those with severe sciatica, significant leg weakness, or bowel or bladder changes, surgery may be necessary.
The following are the sign and symptoms of sciatica:
- Moderate to severe pain in the lower back, buttock and back of the leg.
- Weakness or numbness in the lower back, buttock, legs, or feet.
- Pain that worsens when coughing, sneezing, sitting, or standing for a long period of time.
- Loss control of bowel or bladder.
It is recommended to see a doctor if the symptoms persist, especially if the pain lasts longer than a week or worsens. If the condition is mild, it may improve on its own over time.
The following condition may lead to sciatica:
- Herniated or slipped disk: The most common cause of sciatica is herniated disk. The spine consists of vertebrae that are separated by cushioning pads called disks. A herniated disk occurs when the pressure from the vertebrae causes the gel-like center of the disk to protrude through a weak point in its outer wall. If this occurs in the lower back vertebrae, it can put pressure on the sciatic nerve.
- Spinal stenosis: This occurs when the spinal canal narrows abnormally, reducing the space for the spinal cord and nerves.
- Spondylolisthesis: Spondylolisthesis is a condition where one vertebra slides out of alignment with the vertebra above it, causing a narrowing of the nerve exit. This can lead to the sciatic nerve being compressed by the stretched spinal bone.
- Osteoarthritis: As spine age, bone spurs (jagged edges of bone) can form and put pressure on the lower back nerves.
- Tumors: If the tumor develop in the lumbar spine, it can cause compression at the sciatic nerve.
- Piriformis syndrome: Piriformis syndrome is a rare neuromuscular disorder that occurs when the piriformis muscle in the buttocks becomes tight or goes into spasm. This can result in pressure and irritation of the sciatic nerve.
- Cauda equina syndrome: Cauda equina syndrome is a serious and uncommon disorder that affects the cauda equina, a bundle of nerves located at the end of the spinal cord. Symptoms include leg pain that radiates down the leg, numbness around the anus, and loss of control over bowel and bladder functions.
Below are some factors that increase the risk of developing sciatica:
- Age: As people age, changes and movements in bone, disks, and ligaments may increase the risk of nerve injury or pinching due to aging-related changes in the spine, such as herniated disks and bone spurs.
- Obesity: The spine can be thought of as a vertical crane, with your muscles serving as the counterweights. The heavier the weight you carry in the front of your body, the harder your spine (crane) must work to lift it. This can put additional strain on your back muscles, potentially leading to back pain, strains, and other issues.
- Injury: Sciatica is more likely to occur following a lower back or spine injury.
- Physical work: Jobs that heavy lifting or prolonged sitting can increase the risk of low back issues.
- Pre-existing conditions: Pre-existing conditions such as diabetes and osteoarthritis can increase the risk of nerve damage and spinal damage.
- Lifestyle: A sedentary lifestyle and lack of exercise can increase the risk of sciatica, as well as smoking, which weakens bones, damages spinal discs, and accelerates disk degeneration due to the nicotine in cigarettes.