Minor leg problems, such as sore muscles, are common. Leg problems commonly occur during sports or recreational activities, work-related tasks, and work or projects around the home. Leg problems also can be caused by injuries. If you think your leg problem is related to an injury, see the topic Leg Injuries.

Leg problems may be minor or serious and may include symptoms such as pain, swelling, cramps, numbness, tingling, weakness, or changes in temperature or color. Symptoms often develop from exercise, everyday wear and tear, or overuse.

Older adults have a higher risk for leg problems because they lose muscle mass as they age. Children may have leg problems for the same reasons as adults or for reasons specific to children. Problems are often caused by overactivity or the rapid growth of bone and muscle that occurs in children.

It may be helpful to know the structure of the leg to better understand leg problems. See pictures of:

• Bones of the lower leg and the thigh .
• Muscles and tendons of the lower leg.

Leg problems that are not related to a specific injury have many causes.

• Overuse injuries may occur when you "overdo" an activity, do the same activity repeatedly, or increase your exercise. Examples of overuse injuries include bursitis, tendinitis, shin splints, stress fractures, or plantar fasciitis. Muscle cramps can be caused by activity or dehydration, especially when you exercise in the heat. For more information, see the topic Dehydration.
• Problems that affect the blood vessels (vascular disease) can include peripheral arterial disease, inflammation of a vein (phlebitis), or a blood clot (thrombophlebitis).
  • A blood clot near the surface of the skin may cause only minor problems, while a clot in a deep vein may be more serious. Recent surgery, especially on bones or the pelvic or urinary organs, increases the risk of blood clots, especially in deep leg veins. Prolonged bed rest and inactivity, including sitting or standing in one position for long periods of time, or prolonged immobilization of a limb, such as in a cast or splint, also may increase the risk of blood clots.
  • Problems affecting the arteries (peripheral arterial disease) can cause cramping pain that occurs with predictable amounts of exercise, such as walking a short distance, but improves with rest.
• Other diseases, such as osteoarthritis, rheumatoid arthritis, and lupus, can cause joint pain, stiffness, and swelling. A transient ischemic attack (TIA) or a stroke can cause numbness, tingling, or loss of function in one or both legs.

Some leg problems are seen only in children, such as swelling at the top of the shinbone (Osgood-Schlatter disease) and swelling and pain in the knee joint (juvenile idiopathic arthritis). Growing pains are common among rapidly growing children and teens and are probably caused by differences in growth rates of muscle, bone, and soft tissue. These pains often last for 1 or 2 hours at a time and can wake a child from sleep.