A variety of disorders can be responsible for pain in the calf. Common causes include muscle strain, cramp and sciatica (inflammation of the sciatic nerve). More rarely, pain calf muscles may be due to blood clots in leg veins (see thrombosis). This disorder is a particularly risky for a person that has been immobile for a long time – for example, during a long journey by air or after surgery. Another potential problem is claudication (cramping pain usually due to the narrowing of arteries). In this last condition, pain is generally caused by walking and comforted by rest.