Discs are spongy structures located between each pair of spine bones or vertebrae that help provide flexibility and shock absorption to the spine. Each disc is composed of a tough outer “shell” called the annulus fibrosus and a softer gel-like interior portion called the nucleus pulposus. Normally, these discs rest between each pair of vertebrae and facilitate the normal motions of the back. But sometimes, a disc can slip out of place. When this happens, the edges of the discs can be compressed and “pinched” or herniated by the vertebrae, causing inflammation, irritation, and pain. Sometimes, a portion of the disc can break away and the disc can rupture, leaking some of the gel-like interior material into the area around the spine and increasing irritation on the surrounding nerves. Herniated discs can occur as a result of repetitive movements like bending and lifting, sitting or standing for long periods of time, or car accidents or slip-and-fall accidents. Pregnancy and being overweight can also cause the discs to move out of alignment, and some spinal diseases including degenerative diseases also may play a role.
Herniated discs can cause acute and chronic pain in the area of the back where the disc has slipped out of place, as well as radiating symptoms of pain, numbness and tingling in the arms and legs. These radiating symptoms occur because the inflamed disc can press against or crowd nerves as they exit the spine, causing painful nerve sensations anywhere along that nerve pathway. Sciatica in the lower back and cervical radiculopathy in the neck are two conditions that may be caused by herniated discs and which can result in radiating symptoms in the legs or the arms.
In very mild cases, physical therapy, rest, and medication can help relieve symptoms, and injections into the area around the spine can also help by relieving inflammation. When symptoms are caused by a degenerative disease, minimally-invasive surgery may be needed to resolve symptoms and prevent recurrence.