Causes of Calf Pain
Pain in the calf is commonly felt following muscular injury from sporting activities which tend to involve running, lunging, jumping or hopping related movements. In the majority of cases it will relate to injury of the gastrocnemius with symptoms being localised as pain in the calf muscle. The deeper soleus muscle is sometimes also injured but to a lesser extent with the pain being felt more deeply. Both types of muscular injury would produce calf pain when walking.
Pain behind the knee and calf could be related to a muscle injury but may have another cause. Frequently the knee joint can refer symptoms which are perceived as upper calf pain. This is usually due to pathology in the knee and therefore needs to be assessed by a physiotherapist to help ascertain the cause.
Injury to a nerve in the back can also produce pain in the calf of the leg but often symptoms may be felt higher up, including the hamstring and buttock.
If you have leg calf pain with lots of swelling and no obvious trauma then it is very important to seek more urgent medical advice as it may be caused by deep vein thrombosis. However if there has been a clear trauma then it is more likely to be muscular injury.