Severe strain requires surgical repair. Chronic strains are caused by overuse. Acute strains are caused by direct injury or overstress. Muscle attached to the Achilles' tendon. Pain when flexing or extending the foot.
Muscle spasm at the rear of the calf.
Swelling around the Achilles' tendon. Inflammation of the sheath covering the Achilles' tendon. Prolonged overuse of muscle-tendon units in the ankle. Sports that require quick starts, such as long-jumping, hurdling or running races. Any cardiovascular medical problem that results in decreased circulation.