What are the signs of femoral neck fracture necrosis

Femoral neck fractures are not uncommon, but we all know that femoral neck fractures do not necessarily lead to necrosis, so there is no need to worry too much about it. Usually, we should pay attention to local care and understand the symptoms of femoral head necrosis. Only in this way can we know how to take effective treatment measures as soon as possible.

1. Incidence

Whether femoral head necrosis (AVN) occurs after a fracture depends mainly on the degree of vascular damage, especially the posterior superior retinacular artery, which is crucial for the blood supply to the femoral head. If the fracture is more displaced, the probability of injury to the artery increases significantly. Furthermore, depending on the revascularization, adequate blood flow can be restored before the femoral head collapses. The difference in the incidence of AVN after femoral neck fracture lies in the different patient group data, follow-up time, and different criteria for diagnosing AVN. The probability of necrosis and collapse of displaced femoral neck fractures is approximately 16% to 30%, while that of non-displaced fractures is approximately 8% to 15%. Factors that affect fracture healing also affect AVN. For example, subcapital fractures, significantly displaced fractures, excessive valgus reduction, and internal fixators that occupy more space in the femoral head can all increase the incidence of AVN.

2. Symptoms

The symptoms of femoral head necrosis vary greatly. Mild cases may be painless, while severe cases may cause complete loss of joint function. The symptoms are related to the scope of necrosis, degree of collapse, and degree of involvement of acetabular cartilage. The most fundamental cause is the degree of aseptic inflammatory response of the synovial membrane.

The X-ray findings were not completely proportional to the clinical symptoms. Although the X-rays showed partial collapse, 71% of the patients were asymptomatic or had good functions and did not require further active treatment. Early femoral head necrosis does not mean that surgery is needed as soon as possible. The disease progresses more significantly in young patients than in the elderly, and most of them often require surgical treatment in the later stages.

3. Treatment

The treatment of femoral head necrosis cannot be based solely on imaging manifestations, but should mainly refer to the patient's symptoms and signs. Early femoral head necrosis can be treated conservatively with medication and reduced weight-bearing, or various types of hip-preserving surgeries can be performed, such as lesion removal, compression bone grafting, fibula support, various bone flap or bone-muscle flap implants, etc. For patients in the advanced stage with severe symptoms, hip replacement surgery may be an option.