The sciatic nerve is the longest nerve in the body, extending from the lower spinal cord to the back of each foot. Sciatica is often thought of as a condition. Instead, sciatica is a term that describes the symptoms related to compression of the sciatic nerve. These symptoms include pain, numbness, tingling and burning sensations. The Mayo Clinic states that sciatica pain usually resolves on its own in four to eight weeks. However, some cases may be more severe and permanent.
Herniated Disk
A herniated disk is the most common cause of sciatica pain. A disk is a fibrous circular tissue between each vertebra that acts as a shock absorber and increases the flexibility of the spinal column. A disk can slip out of place and put pressure on the spinal nerve exiting the spinal canal. If this occurs in the lower spine, sciatica pain is likely to occur, states Medline Plus. A large majority of herniated disks heal with rest and physical therapy.
Piriformis Syndrome
The piriformis muscle is located in the buttock region and runs over the sciatic nerve. The Mayo Clinic states that piriformis syndrome occurs when this muscle becomes too tight or spasms and compresses the sciatic nerve, causing sciatica pain. Piriformis syndrome sciatica pain can be differentiated from sciatica in the back because this type of pain does not extend beyond the knee. Like a herniated disk, sciatica pain associated with piriformis syndrome will usually heal with rest and physical therapy.
Lumbar Spinal Stenosis
The spinal cord is protected in a bony canal that runs through the vertebra. With age, osteoarthritis can affect the vertebra and create bony humps in the spinal canal that can compress the spinal cord, states the Mayo Clinic. If the canal becomes narrow in the lower back, it can result in sciatica pain. Conservative treatments can be helpful, but surgery may be necessary in severe cases.
Spondylolisthesis
Spondylolisthesis is a condition in which one vertebra slips out of place, according to the Mayo Clinic. If this occurs in the lower back, the displaced vertebra can pinch the sciatic nerve and sciatica pain may occur.
Spinal Tumors
The Mayo Clinic states that spinal tumors can be a cause of sciatica pain. A tumor may originate in the spine or cells from a tumor in another part of the body can migrate, or metastasize, to the spinal vertebra and spinal cord. Treating the primary tumor is important in reducing the spread of more tumors to the spinal cord. After the primary tumor is located and controlled, systemic cancer treatment can reduce spinal tumors and the associated sciatica pain.
