Necrosis of the femoral head usually does not cause fever, so you can not judge the severity of the disease based on the symptoms of fever. In osteonecrosis of the femoral head, fever is less common among clinical symptoms. Fever may be due to inflammation, such as influenza, mumps, meningitis, etc., which may cause pulmonary fibrosis, submandibular gland swelling, etc., but it has nothing to do with femoral head necrosis itself, so the fever of the patients with femoral head necrosis can not assess the severity of the disease. When the condition of necrosis of the femoral head worsens, patients usually have limited joint movement, and in severe cases, it may cause pain in the joints, which makes it impossible to move normally, and the symptoms may radiate to other parts of the body as well. If you are concerned about the worsening of necrosis of the femoral head, you should have regular checkups.