Some causes of leg pain: Even a minor injury can cause leg pain. Arthritis can also cause leg pain. Muscle contractions can also cause pain. If there is tension in the muscles, then there may be pain in the legs as a result of the knee joint. Old age , not wearing comfortable shoes , walking too much ... various types of fractures , lack of minerals in the body , diabetes etc. can also cause leg pain due to various physical reasons. Leg pain is caused by weak muscles , lack of nutrition , dehydration , muscle tension , prolonged walking or standing.