Pain on the side of the heel may be caused by the following reasons: First, it may be caused by osteoporosis here, a condition often seen in the elderly, who are more or less likely to have osteoporosis. This condition in the heel bone often manifests itself as some vague soreness on the lateral side of the heel, and in severe cases it can lead to very obvious swelling and soreness. Second, may be due to the metatarsal tendonitis, such diseases are mainly due to the front of the heel bone metatarsal tendon membrane for a long time to maintain excessive tension, followed by a series of sterile inflammation. In this case, it will lead to very obvious pain on the lateral side of the heel bone, especially on the medial side of the heel bone. This pain can be significantly increased after the patient puts weight on the ground or walks long distances. Third, it may be caused by the high pressure of the heel bone, which is often due to the presence of some old injuries to the heel bone, such as contusions or fractures of the heel bone, which may increase the pressure inside the heel bone after its recovery, thus leading to pain. Fourth, due to long-term excessive compression, for example, the patient wears shoes that are too crowded, which may cause long-term compression and friction, which may lead to skin damage or soft tissue inflammation, resulting in pain.