The neck of the femur

Definition

The femoral neck is a section of the femur (Os femoris, femur). The femur can be divided into four sections. The femoral head (caput femoris) is followed by the femoral neck (collum femoris).

This finally merges into the femoral shaft (corpus femoris). Finally, the femur has two bony protrusions (condyli femoris) at knee level, which are involved in the construction of the knee joint. The neck of the femur itself lies for the most part in the articular cavity of the hip joint and is surrounded by the joint capsule.

Anatomy

Anatomically, the neck of the femur (collum femoris) is a part of the femoral bone (os femoris, femur). It represents the connection between the femoral head (caput femoris) and the femoral shaft (corpus femoris). The neck of the femur is angled towards the femoral shaft in the direction of the middle of the body.

This angle is called the CCD angle (Caput-Collum-Diaphyseal Angle) and is approximately 126°. If the angle exceeds this value by about 10°, it is called a coxa valga, if it is smaller than 120°, it is called a coxa vara. The neck of the femur merges into the femoral shaft.

Two anatomical structures are conspicuous at this transition. The greater trochanter and lesser trochanter are two bony prominences from which different muscles originate. The neck of the femur is also involved in the construction of the hip joint.

It is surrounded by a joint capsule in two-thirds of its size, but is not involved in the direct mechanics of the hip joint. Nevertheless, it is completely surrounded by the so-called synovial membrane, which ensures the nutrition of the joint and the smooth movement of the femoral head in the acetabulum. Several blood vessels (collum vessels) also run directly along the neck of the femur and supply the femoral head. Furthermore, the neck of the femur is covered by a strong ligamentous apparatus, which secures the hip joint and makes it only slightly susceptible to dislocation.