There are several reasons for the symptoms of lumbar pain and leg swelling: 1. The symptoms may be caused by a herniated lumbar disc pressing on the nerves, which, in addition to the discomfort in the lumbar region, can cause painful nerve pulling in the muscles of the buttocks, thighs or calves, or numbness and soreness. 2. It may be caused by the third lumbar transverse process syndrome, because when the third lumbar transverse process is inflamed, it can lead to the lumbar The lumbar muscle affects the lumbar nerve roots, resulting in soreness and pain in the anterior lateral or medial thigh muscles. 3, may be due to the abnormal accumulation of lactic acid in the body after strenuous exercise, resulting in pain and swelling in the waist and legs. Therefore, if the symptoms of lumbar pain and leg swelling appear, if there is no relief within a short period of time after bed rest, you must go to a regular hospital in time to improve the necessary relevant tests and choose a reasonable treatment method after clarifying the cause.