What Diseases Can Cause Severe Leg and Foot Pain?

Leg pain may be caused by muscle cramps, inflamed tendons, deep vein thrombosis and peripheral arterial disease, according to WebMD. A broken bone or a sprained knee or ankle may also cause pain through the leg.

Intense physical activity may cause injury or pain to muscle, bones, tissue and tendons, as explained by WebMD. Often caused by muscle fatigue or dehydration, muscle cramps can create a sudden tight pain in the leg. Connective tissue and muscle may become inflamed, causing shin splints. This is typically the result of running or jumping on a hard surface such as pavement. Tendonitis, a torn tendon or muscle may also cause pain in the lower calf or heel. Severe pain in the back of the heel may be the result of a torn Achilles tendon.

Certain conditions in the veins, such as blood clots and varicose veins, may also cause leg pain, as WebMD explains. Blood clots in the form of deep vein thrombosis can develop in the lower leg or thigh, and while they are usually caused by lack of movement over long periods of time, they may also form as the result of smoking, being overweight and taking certain medications. Varicose veins appear as dark blue or purple veins, and they cause a dull ache. Peripheral arterial disease is a condition of damaged or hardened arteries, which causes poor blood circulation, leg pain and cramping. Those with high blood pressure, high cholesterol or diabetes are at high risk for peripheral arterial disease.