Symptoms
A femoral neck fracture is usually accompanied by severe pain, which can be aggravated by an attempt to move the hip joint and especially by pressure on the large rolling mound, the so-called trochanter major. Rarely and especially in the case of compressed and non-displaced fractures, only moderate pain occurs, which can be confused with a bruise of the hip. As a rule, however, those affected complain of severe pain, which increases with the degree of displacement of the fractures and is no longer able to walk.
For the experienced examiner, the detection of a femoral neck fracture is usually a gaze diagnosis, characterized by shortening and external rotation of the injured extremity. The external rotation is caused by muscle traction of the buttocks muscles that attach to the greater trochanter. The shortening of the limb results from the displacement of the fracture line or even from the extremely painful tilting of the femoral head. Depending on the cause of the accident, bruising may occur in the area of the hip joint.
Diagnostics
The suspected diagnosis, which can usually already be made on the basis of the accident mechanism and the typical position of the injured leg, is supplemented by further diagnostic steps. During the physical examination, a pressure painfulness over the large rolling hill and the movement painfulness during mobilization of the hip joint are examined. Within the framework of fracture diagnostics, the blood circulation of the lower extremity is checked by detecting the foot pulses and maintaining sensitivity below the fracture. The admitting physician will also order an x-ray of the pelvis and the femoral head.
Classification of the fracture according to Garden and Pauwels
The classification according to Pauwels is done by determining the angle of inclination of the fracture line. In the clinic, it is most relevant for estimating the severity and prognosis of the injury. The classification into the three degrees of severity is based on the angle between the fracture line and the horizontal.
If this angle is between 0° and 30°, i.e. Pauwels grade I, it is 30° to 50° for Pauwels grade II.An inclination angle of more than 50° is called a shear fracture with the most severe Pauwels grade III. The increasing severity after Pauwels indicates an increasing instability of the fracture. Grades Pauwels II and III are always an indication for a surgical restoration of the bone, a so-called osteosynthesis.
The Garden Classification also indicates a decrease in fracture stability with increasing severity. This classification, which is used mainly in the USA, distinguishes four grades. Garden I describes an incomplete fracture with compression, which is rather stable.
There is no displacement of the fracture fragments. In Garden II, the fracture is complete, but the fragments are still in contact and are not displaced or rotated against each other. The fracture is still stable.
Garden III refers to a complete femoral neck fracture in which the fracture fragments are displaced against each other and the femoral shaft is rotated in relation to the fragment close to the body, but still have contact. This contact is completely eliminated at grade IV of the Garden classification, the fracture fragments do not touch each other at any point, a pronounced dyslocation is present. The prognosis for Garden I and II is good, whereas patients with existing femoral neck fractures classified as Garden III and IV should be treated surgically.