Sciatica is not a disease, but a group of symptoms related to damage to or compression of the sciatic nerve. The sciatic nerve is a large nerve that comes out of the lower region of the spine and travels down the back of the legs. Sometimes, pain from sciatica may go all the way down to the soles of the feet. Sciatica can be caused by a variety of conditions and injuries that put pressure on the sciatic nerve; common causes of sciatica include a herniated (slipped) intervertebral disc in the lower spine, spinal stenosis or narrowing of the spinal canal, traumatic injury to the low back or pelvis, spasm in the piriformis muscle of the pelvis and spinal tumors.
Symptoms of sciatica usually affect one side of the body, because it is rare for both sciatic nerves to be injured or compressed simultaneously. Sciatic nerve compression causes nerve pain along the path of the sciatic nerve to the buttocks and down the leg, which may vary from mild tingling, burning or aching to severe pain. Some people with severe sciatica pain may have difficulty walking when their nerve pain is acting up. Neuropathy, or nerve damage, can also cause numbness in some areas instead of pain. Pain from sciatica may get worse at night or with certain activities. Muscle weakness may also occur in the legs with sciatica, because the sciatic nerve is responsible for muscle innervation as well as sensory innervation.
Diagnosing the underlying condition is important in cases of sciatica, because the treatments for those conditions may be different. A clinical examination, patient history and medical imaging of the lower back and pelvis can be a part of the diagnostic process. Some causes of sciatica can be treated with anti-inflammatory medications, the use of ice to reduce swelling, and rest. Other causes may require physical therapy, and some cases may require surgery to correct the problem. Most cases of sciatica do not require surgical intervention, and the problem may go away on its own. Some people have sciatica that will go away once the inflammation is reduced, and return when the area becomes inflamed again. Conservative measures for treatment are tried first, unless medical imaging reveals a problem that needs to be treated differently. Prescription pain medications, anti-inflammatory medications and ice may be used, and if these treatments are not enough a doctor may inject anti-inflammatory medications into the area of nerve compression.