what causes severe leg pain?
Deep vein thrombosis, or DVT, a blood clot in a deep vein that develops after extended periods of inactivity, can also cause major leg pain. Long flights or car rides make it difficult for the leg to return blood back to the heart.
Rheumatoid arthritis, an autoimmune disease, attacks the lining of the joints, also causing inflammation and pain. Although arthritis is a joint disease, the pain it causes can be felt in the surrounding leg and foot muscles. âAny joint under stress can cause pain,â Wedro says. âThe pain is within the joints. But the muscles around it try to protect it and you can go into spasms and get secondary muscle pain.â.