Causes of Pain in the Calf

The calf is composed of three muscles: the medial and lateral gastrocnemius, and the soleus. A number of injuries or disorders cause pain in the calf. The most important to consider is deep venous thrombosis.

Calf Strain

The two larger gastrocnemius muscles attach above the knee joint and insert into the heel bone via the Achilles tendon. The smaller soleus muscle attaches below the knee joint and then also to the heel via the Achilles tendon. The most common cause of calf pain is a strain or tear occurring in one or more of these muscles. A calf strain occurs more often in athletes who have tight calf muscles.

Calf Vein Thrombosis

If a physician suspects a deep venous thrombosis, or blood clot, in the leg, she is taught to elicit Homan’s sign, which is the forceful turning of the foot upward, or dorsiflexion, on the affected side when the knee is flexed. A positive sign produces pain. The pain is due to stretching of the posterior tibial vein in the calf.

The gold standard tests to diagnose a blood clot in the leg, according to “Harrison’s Principles of Internal Medicine,” include duplex venous ultrasonography, or venography. A blood clot in the calf or upper leg can dislodge and migrate through the blood to lodge in the lungs. This is called a pulmonary embolus and is life-threatening. Use of a blood-thinning medication such as heparin is one treatment.

Baker’s Cyst

The knee joint is commonly involved in rheumatoid arthritis. Patients may experience pain and swelling at the back of the knee as a result of inflammation in the fluid that lubricates the joint, called synovial fluid. This fluid may extend into the triangular space behind the knee, called the popliteal space, producing a Baker’s cyst, also refered to as a popliteal cyst. If the cyst ruptures, according to, the calf becomes swollen, red and painful.


Cramps in the leg muscles are a common cause of calf pain, as occurs in tennis players during or after a long match. Usually the symptoms are intermittent, and relieved by stretching and heat application.

Intermittent Claudication

According to “Davidson’s Principles and Practice of Medicine,” impairment of blood flow to the legs due to hardening of the arteries, or atherosclerosis, causes intermittent claudication. This condition entails pain in the calf while walking–but the pain is rapidly relieved by rest. The pain also causes the person to limp or stop walking.

About this Author

Based in New Jersey, John Riefler III has been writing since 1987. His articles have appeared in “MD Magazine,” “Emergency Medicine” and “Hospital Practice.” Riefler holds a Bachelor of Science in biology from Bucknell University, a Master of Science in microbiology from M.U.S.C. and an M.D. from St. George’s U. School of Medicine.