Intervertebral discs are protective shock-absorbing pads between the bones of the spine (vertebrae). Disc injuries can occur from a variety of factors such as sports, lifting and rotating under a heavy load, or simply age-related degeneration.

A disc may move, tear, or rupture, causing the outer annular cartilage and nearby tissue to fail, which in turn allows the inner gel portion of the disc to escape into the surrounding tissue. This leaking jelly-like substance can place pressure on the spinal cord or on an adjacent nerve to cause symptoms of sciatica such as pain down the leg, numbness, or weakness either around the damaged disc, or anywhere along the area supplied by that nerve.

Dysmenorrhea is the medical term for painful cramps that may occur immediately before or during the menstrual period.