In the process of clinical consultation, we often encounter patients with femoral head necrosis who have been diagnosed with mid- to late-stage lesions, and when patients are informed of their condition, it is not easy for them to understand how this disease can be. Here are a few typical cases for your reference. A, back pain symptoms mask the real existence of femoral head necrosis Femoral head necrosis can coexist with lumbar spondylosis. Here are several cases: 1, lumbar disc herniation is a common clinical disease, typical cases can show numbness and pain in the lower limbs, especially when there is sciatic nerve pain, it is easy to hide the hip pain caused by femoral head necrosis. In this case, if the doctor gives the patient a CT or MRI examination of the lumbar spine, and there is an obvious lumbar disc herniation affects the scientific performance, it is easier to make the already existing necrosis of the femoral head is missed or misdiagnosed. 2, doctors “preconceived” mode of thinking, easily misled by the patient or family description of the condition, ignoring the basic clinical examination, especially the hip joint examination. Some patients emphasize that they have lumbar disc herniation as soon as they meet with the doctor, and the doctor believes them. The key is that the patient’s previous imaging does have lumbar spondylosis, and no longer insist that the patient be further examined. 3. Indeed, some patients do not have obvious crotch pain symptoms because they are taking medication, and there is no need for the doctor to let the patient do a hip examination. The femoral nerve innervation principle, some patients with osteonecrosis do not have typical crotch pain, but rather knee pain, especially medial knee pain. If the doctor is less experienced and the knee joint examination shows intra-articular degeneration (osteoarthritic manifestations), it is easy to misdiagnose osteoarthritis of the knee joint or miss the already existing femoral head necrosis. There are two cases here: 1. The two diseases do coexist, but the symptoms of osteonecrosis are not typical. 2. Patients show only medial knee pain, but the doctor does not find any knee abnormality on physical examination. When patients have systemic diseases, such as rheumatoid arthritis or ankylosing spondylitis or gout, especially those who receive hormone therapy, the diagnosis is easily missed because of the pain and discomfort of multiple joints. Since it is impossible for patients to know their own condition, clinicians, especially primary care physicians, are required to improve the popularity of the basic clinical examination, rather than simply listening to what patients and their families say or believing in the results of the tests that patients have undergone. Patients should understand that when the clinical treatment for lumbar spondylosis or knee arthropathy has not been effective for a period of time, they should look at the hip joint to see if there are any problems.