Another patient with moderately advanced femoral head necrosis was recently admitted to the hospital for surgical treatment. This patient had some special features. He was in his fifties and male. He had been treated for lumbar disc herniation in a local hospital for three years because of pain in the lumbar g region. During this period, he had a lumbar spine X-ray, lumbar CT and MRI scan. He did have herniation of the lumbar 4/5 and 5/S1 gaps on imaging, but neither was severe. He was treated by local doctors with medication, closure and even traction, but no definite results were achieved. As time went on, the pain behind his right g became worse and worse, he could not ride a bicycle, could not put on socks smoothly, walked with a cramp, and then felt as if his right leg had become shorter. Then he changed to the nth hospital, took a pelvic X-ray, and the doctor told him you have femoral head necrosis, go to a big hospital. When I talked to the patient before surgery, I found that this patient never had lower limb numbness despite having back g pain, and his leg pain never went below the knee joint. He basically does not drink alcohol in his daily life. He had only been hospitalized for a week before N for eye disease and seemed to have been on hormones for a while. Before the surgery, I had a new X-ray examination and found bilateral femoral head necrosis, stage IV on the right and stage ll on the left. After the healing period of the incision on the right side, all the original symptoms of lumbar g disappeared. Similar cases can be seen in many clinical settings. When patients visit the clinic, based on the lack of medical knowledge and the vague boundary of symptoms, many times they cannot describe them accurately. Further the lumbar symptoms are connected to the g symptoms due to the anatomical region and there is vague localization. The key is that the receiving physician may prefer lumbar examination when the patient has lumbar symptoms due to the limitation of knowledge, and the examination result is positive, so he or she treats the patient endlessly according to lumbar disc herniation. Most of these patients have a long and rich clinical history of consultation, and because the previous examination did have the presence of lumbar disc herniation compression, he was confused even if the presence of femoral head necrosis was later confirmed, and even suspected that you were mistaken. Here is a word of warning to patients: 1. As a pathological change, herniated lumbar disc nucleus pulposus is very common, especially in adult manual laborers and sedentary office workers. Many times this herniation coexists peacefully with you and does not add to your problems. 2, On imaging, lumbar disc herniation can coexist with hip pathological changes such as femoral head necrosis or osteoarthritis of the hip joint. 3.When two or more pathological factors are present, the doctor will help you determine which one is really causing the clinical symptoms. 4.If the lumbar g pain does not improve after a period of treatment according to lumbar disc herniation, remember to check the hip joint, or even the knee joint.