In general, the bone will repair itself after fracture reset, but there are special, there are places where the position is good again after fracture, it does not heal, and there is ischemic osteonecrosis, ischemic osteonecrosis after fracture, also known as aseptic necrosis, mostly seen in femoral neck, hand navicular and foot talus, with ischemic osteonecrosis of femoral neck more common. The normal femoral head is polished like jade, with the shape of a ball, placed in the lateral acetabulum of the pelvis, forming the hip joint and moving freely. However, because people walk upright, the femoral head of both lower extremities are under great stress and relatively insufficient blood supply. This fracture is not only difficult to heal, but also prone to ischemic necrosis. If the elderly into osteoporosis, slow response, prone to femoral neck fracture, about 1/3 of the elderly after the fracture occurred ischemic necrosis of the femoral head. Initially, the surface of the injured femoral head loses its luster and gradually becomes rough and uneven, with depressions appearing, and eventually the femoral head may be collapsed and flattened, becoming smaller or even disappearing completely. In the early stage, the symptoms are mild, and the patient feels only mild hip pain, which may be accompanied by knee pain. The pain gradually worsens and becomes obvious when standing or walking. Over time, the hip joint movement is affected, and claudication occurs. There are many ways to treat ischemic necrosis of the femoral head. First of all, we should try to promote the healing of the femoral neck fracture, if the fracture has healed, but the femoral head is necrotic, early on, we should reduce standing and walking, and use crutches to reduce the weight, and exercise can be done according to this principle. And physical therapy, hyperbaric oxygen, magnetic therapy and medication can be used for treatment. If the effect is not good, or if the lesion is serious, surgery can be performed. The following surgical methods are commonly used: First, osteotomy. The upper end of the femur is truncated to change the line of negative gravity so that the necrotic part of the femoral head is no longer under pressure and to relieve pain. This method works well but leaves a mild claudication. Second, arthrofusion. The diseased hip joint is fused together and is no longer active. This method can completely relieve the pain entanglement, but the loss of hip mobility and limp are obvious, which has certain impact on work and life, such as squatting and defecation is very inconvenient. Thirdly, to rebuild the blood circulation of the femoral head and improve the blood supply. If the trunk and branches of the lateral spinococcygeal artery near the femoral head are carefully separated to form a bundle and transplanted into the necrotic femoral head, it is called vascular bundle implantation method. Or an iliac bone block with the deep spinococcygeal artery is transplanted into the femoral head. Radiological intervention is the use of a puncture technique in which a catheter is delivered into the femoral artery under fluoroscopic X-ray supervision and injected with thrombolytic drugs such as urokinase, low-molecular dextran, and compound salvia injection, supplemented by intravenous drips of urokinase and oral calcium to enhance the efficacy and improve the blood supply to the femoral head. In addition, some people have measured and found that the pressure inside the necrotic femoral head is elevated, so a central femoral head drilling and decompression can be used. Some people also introduce the use of fracture stimulating healing agent, or autologous bone marrow injected into the femoral head to promote bone growth and repair. If all these methods fail to solve the problem, artificial joint replacement is feasible. The navicular bone of the hand and the talus of the foot are surrounded by almost all articular surfaces, with few nourishing blood vessels, and the nutritional pathway is cut off due to the damage caused by the fracture. The treatment principle is the same as that of ischemic necrosis of the femoral head. In the case of osteonecrosis of the navicular bone, the necrotic part of the hand is mostly removed, and in the case of osteonecrosis of the talus, bone graft fusion is often performed. Therefore, once the doctor diagnoses the above-mentioned fracture, we must actively treat it, and never take it lightly and delay the time.