Classification of the femoral neck fracture

Femoral neck fractures can be classified according to three different schemes. There is the scheme according to Garden, the scheme according to Pauwels and the AO classification. In Germany, the AO classification is the most common.

In the Garden classification, four degrees of severity are used, whereby the deviation of the individual fracture parts (dislocation) is the main factor. In Garden Grade I and II there is only a slight dislocation of the femoral head to the femoral neck. In these two cases, the prognosis is very good with early treatment, so that surgery is not always necessary and complications in the course of the disease rarely occur.

Grade III and IV are more difficult to dislocate and must be brought into the correct axial position immediately. In addition, surgery is almost always indicated. In the course of Garden Grade III and IV, severe complications such as necrosis of the femoral head or the development of pseudoarthrosis occur more frequently.

The classification according to Pauwels has rather an academic value in medicine. Pauwels distinguishes three different degrees of severity. A horizontal line is drawn over the X-ray image and the angle between the horizontal and the fracture line is measured.

Pauwels I describes a spread of the femoral neck up to 30 degrees. Between 30 and 50 degrees is called a Pauwels II femoral neck fracture. From 50 degrees on, stage III is reached after Pauwels. The higher the degree of severity after Pauwels, the worse the prognosis for the patient.

Therapy

The femoral neck fracture almost always represents an indication for surgical treatment. There are different approaches to treat the fracture. Which type of operation is performed is decided on the basis of various factors.

These include above all the age of the patient, but the localization and type of fracture also play an important role. There are essentially two different approaches to the operation of the femoral neck fracture: hip head preservation or with an endoprosthesis. On the one hand, an attempt is made to preserve the femoral head and not to replace it with a prosthesis.

This approach is particularly useful for young patients, as the joint is often only slightly damaged. The fracture is treated with different screws and plates, which differ in form and function depending on the fracture. A special type of screw is the so-called dynamic hip screw (DHS).

The DHS is primarily used for lateral (lateral) and pertrochanteric (between the two bone elevations) femoral neck fractures. The dynamic hip screw is used to press the individual bone fragments increasingly together so that they can grow together as physiologically as possible. The major risk associated with the femoral head preservation strategy is so-called femoral head necrosis.

This is caused by the fact that the fracture can obstruct the blood supply to the bone in the region of the femoral head. As a consequence, the bone dies irreparably and must be surgically removed to avoid serious complications. It is therefore important to treat the femoral neck fracture in young patients as early as possible to prevent femoral head necrosis.

In this case, the operation is considered an emergency intervention. This is different in older patients with a femoral neck fracture.The surgery can be planned more easily, since the fracture does not need to be treated immediately. In most cases, hip prostheses are used for the treatment.

Either only the femoral head can be replaced or the acetabulum can also be replaced. The procedure is decided individually by the patient. Advantage: A great advantage of using prostheses is that patients can and should put weight on their leg again immediately after the operation.

Especially with older patients, bedriddenness is a major problem in medicine and can be prevented by this treatment strategy. Risk: A major risk when introducing foreign bodies into the patient is infection. If the infection occurs and cannot be controlled conservatively with antibiotics, another operation may be necessary to remove the prosthesis.