Femoral head necrosis is very common in clinical practice and mainly refers to the destruction, deformation and collapse of the femoral head. Patients may present with pain and limited movement of the hip. Decreased and interrupted blood supply is the direct cause of femoral head necrosis. The common clinical causes of femoral head necrosis are as follows. 1. Severe trauma to the lower limbs, resulting in femoral neck fracture and joint dislocation, which induces interruption of blood supply to the femoral head and leads to necrosis of the femoral head. 2. Long-term heavy alcohol consumption leads to alcoholism, which induces necrosis of the femoral head. 3, long-term use of corticosteroids or adrenal corticosteroids can produce side effects, leading to necrosis of the femoral head. 4. People who receive radiation for a long time are prone to develop necrosis of the femoral head. 5, Some people with special occupations, such as divers, pilots, tunnel workers, etc., have a higher probability of femoral head necrosis than people in other occupations. 6, Patients with SLE, sickle cell anemia, hypertension, and diabetes are prone to femoral head necrosis. In conclusion, necrosis of the femoral head is mainly caused by the reduction and interruption of blood. The occurrence of osteonecrosis can be prevented by actively removing the causative factors. Eating more calcium-rich foods such as shrimp and bone broth can prevent osteonecrosis.