Fracture Neck of Femur
Fracture of the femur neck is considered a "fracture of necessity" as it necessitates an open surgery for optimal results. It is usually seen in elderly individuals as a result of a fall and those who have an unsteady movement or walk and have weak bones. It can also occur in younger individuals due to high velocity injuries like motor vehicle accidents.
For elderly individuals, fracture of the femur neck can be a major cause for morbidity since it leaves most patients motionless. This can further worsen the situation due to pressure sores, chest infections, lack of proper nutrition and minerals and depression. Surgery is recommended as a logical choice even in elderly individuals with multiple disorders to increase mobility which can prevent other medical complications related to being confined to a bed. Studies have shown that in spite of risks, the benefits of surgery are far superior to non-operative treatment.
Fracture neck of femur is broadly classified as intracapsular and extracapsular fractures.
- Intracapsular fractures: are those where the fracture occurs within the joint capsule. These fractures are associated with a higher risk since the union of the fracture is required for necessary blood supply to the femoral head, the highest part of the thigh bone connected to the hip.
- Extracapsular fractures: on the other hand, occurs outside the joint capsule, usually in an area of superior blood supply and hence fracture union is usually not an issue. However, the fractures do have a tendency to unite in the wrong position.
- X-rays help in diagnosis.
- Further information can be obtained by doing CT scans. This is however, not always necessary.
The surgeon decides on the appropriate surgical choice based on several factors, most important of which is position of the fracture.
Intracapsular fractures in elderly individuals are usually treated by hemiarthroplasty which is essentially a half hip replacement where the femoral head (ball) is replaced by a metallic prosthesis. Recent studies have shown that a total hip replacement may be superior to hemiarthoplasty, but results of long term studies are still awaited.
In younger individuals, an attempt can be made at internal fixation which is a better option than hemiarthroplasty in this age group particularly because of high physical demand. Patients should be informed of the risk of avascular necrosis or non-union which may require further operative interventions. Internal fixation is generally by using screws which are passed across the fracture site. Post-operatively, the patient is mobilised non-weight bearing (till fracture union) if the fracture has been fixed and can be allowed full weight bearing if the femoral head has been replaced.
Extracapsular fractures on the other hand, owing to the superior blood supply in the region of fracture, are amenable to internal fixation. Depending on fracture geometry and stability of the fracture, the fracture may be fixed with a plate and screws called a dynamic hip screw or a nail fixed into the bone, medically called an intra-medullary device. Patients are usually mobilised partial weight bearing after surgery and the results are generally good.