Femoral head necrosis, also known as ischemic necrosis of the femoral head, is a pathological process of ischemic osteonecrosis of the femoral head due to various causes of impaired blood circulation in the femoral head, and is an orthopedic disease with a high disability rate. At present, there are not many effective methods to treat osteonecrosis of the femoral head, and patients in advanced stages often need to replace the artificial head of the femur, and the quality of life becomes poor, so early detection and early treatment is the key to effective treatment of osteonecrosis of the femoral head. A, the symptoms of femoral head necrosis: The symptoms of femoral head necrosis are mainly pain, limited activity, claudication three major symptoms: 1, pain: general patients can appear hip pain, can also have lumbosacral, knee pain. The nature of the pain is soreness and tingling, etc. The pain symptoms can be aggravated by walking or after exertion. The pain is mild in early stage patients and usually cannot be taken seriously by patients or misdiagnosed as other diseases. In the middle and late stage, the hip pain is sometimes light and sometimes heavy, and the disease can become progressive aggravation, which should be taken seriously. 2, limited activity: early stage patients can have normal or slightly limited hip joint activity, manifested as impaired activity in one direction, commonly restricted in the direction of internal rotation. In the middle and late stage, the restriction of hip joint activity can be gradually aggravated, manifesting as restriction in multiple directions, such as abduction, adduction, internal rotation, internal and external rotation, forward flexion and back extension. It may affect the normal activities of patients such as wearing shoes and socks and squatting. 3.Crippling: It manifests as unstable walking due to pain, and in severe cases, the body sways from side to side. Early stage patients may have intermittent claudication due to increased pressure in the femoral head, which improves after rest. In the middle and late stage, patients may have persistent claudication due to femoral head collapse, pelvic tilt and hip joint subluxation. Early diagnosis of femoral head necrosis Early diagnosis of femoral head necrosis is difficult, and patients are often delayed due to unclear understanding of the disease. Among them, MRI is more sensitive to the diagnosis of early femoral head necrosis, with a high positive rate. x-ray films can not see abnormalities in the early stage. Third, the treatment of femoral head necrosis femoral head necrosis only early treatment can be effective, late patients have collapsed the femoral head deformation, can not restore the original shape, can only be replaced with artificial femoral head. The ultimate goal is to improve the blood supply to the femoral head and promote the absorption of necrotic bone and the growth of new bone in the femoral head. Interventional lysis for early stage femoral head necrosis is a direct method to achieve this goal. Interventional lysis can improve the blood supply to the femoral head by directly injecting thrombolytic and vasodilator drugs into the blood supply artery of the femoral head. The method is to inject the drugs with the functions of dissolving thrombus, activating blood circulation, dilating blood vessels and improving microcirculation directly into the blood supply artery of femoral head through cannula, and to improve the blood supply to the femoral head of the affected limb, increase the collateral circulation, unblock the nutritive blood vessels of the femoral head, promote the proliferation of osteoblasts and the resorption of osteoclasts, so that the necrotic bone is gradually absorbed and new bone is formed, and the femoral head is gradually repaired. It is easy, painless and reliable.