Fractures of the neck of the femur usually pass through the necrotic phase after 5 years. The incidence of femoral head necrosis in femoral neck fracture is related to the type of fracture, diagnostic criteria, age, treatment method, number of follow-up cases and years of experience, so there is a large individual variation. The occurrence of femoral head necrosis is mainly based on the X-ray presentation. According to relevant studies, the earliest time for necrosis to occur after femoral neck fracture is 6 weeks after the injury, and the latest time is 17 years after the injury. In the group of patients with femoral head necrosis, the incidence of necrosis is 80% to 90% within 3 years, 19.6% within 1 year, 39.2% within 2 years, 23.5% within 3 years, and 8% within 4 years, which means that 98% of femoral head necrosis occurs within 5 years. Therefore, it should be closely observed 2 to 3 years after the injury and should be followed up until 5 years after the injury. Timely and standardized treatment after femoral neck fracture is necessary to avoid the occurrence of femoral head necrosis and timely review.