Radiating back pain is any type of pain in the back that radiates, or spreads, to another part of the body. The most common cause of radiating back pain is a pinched nerve; this occurs when a muscle, bone, or other part of the body compresses around a nerve ending, sending pain throughout the entire area of the body connected to that nerve. One of the most common types of radiating back pain is sciatic nerve pain, in which a muscle or bone in the lower back compresses on the sciatic nerve. The pain then radiates through the lower back, buttocks, and legs.

The sciatic nerve is a long nerve that runs from the lower back to the bottom of the leg. If a muscle compresses the nerve at any point along its length, pain can be felt throughout the course of the nerve. Very commonly, a muscle in the leg might compress the nerve — especially if the person spends a significant amount of time sitting in a chair — and radiating back pain may occur. The nerve may also get pinched somewhere in the lower back or hips, sending pain down the leg. In either case, the point of compression is not always necessarily the place where pain is felt.

Other causes of radiating back pain may have more to do with muscles compensating for the failure of another muscle. If, for example, a muscle in the lower back becomes strained or torn, other muscles in the back, legs, or even stomach may overcompensate to keep the spine supported. The original site of pain where the injury occurred may give off a sensation of radiating outward as other muscles struggle to support the spine. This may lead to subsequent muscle strains or tears, and the sufferer should allow for ample recovery time before attempting physical activity.

Other nerves within the back can cause radiating back pain. If such pain occurs, ample rest is needed, though sometimes this is not enough to solve the problem. Over-the-counter painkillers can help relieve some of the pain at least temporarily, but if the pain persists, it may be wise to consult a doctor. He or she might prescribe a stronger painkiller or anti-inflammatory medication to help relieve the cause of the pain rather than just the symptoms. Physical therapy may also be in order, especially if the nerve pain is being caused by a damaged muscle or joint.