Femur

From ArticleWorld

The femur is the most proximal bone in the lower limb of humans. It is the longest and densest bone that must support the weight of the body by its attachment to the pelvis.

Anatomy

Each femur has a rounded proximal end, covered in lubricated cartilage. It represents the “ball” aspect of the ball-in-socket hip joint. A couple of inches further down from the femoral head is a bony prominence called the greater trochanter. The greater trochanter is the point of attachment of several hip-related muscles as well as the iliotibial band, a band of fibrous tissue that runs the length of the femur. On the medial aspect of the proximal femur is the lesser trochanter that is the attachment point of the hip adductor muscles.

The distal femur forms two articular surfaces side-by-side that are called the condyles. These two projections fit into depressions in the proximal tibia to form a part of the knee joint.

Function

The femur participates in the formation of two joints, one at each end. At the two proximal trochanters, muscles attach that participate in hip movement. They also form the attachments of the ligaments that hold the hip joint together.

The bulk of the covering over the femur are muscles that participate in the movement of the knee. The anterior (front) of the femur is covered by a group of knee extensors called the quadriceps muscles. The posterior part of the femur is covered by the knee flexors, also known as the hamstring muscles. The greater trochanter of the femur participates in the attachment of the gluteus maximus muscle and the iliotibial band.

Diseases

The shaft or midportion of the femur is fractured only in serious accidents or injuries. The most proximal part is angulated and is more prone to fracture, particularly in the elderly. The femoral head (or ball of proximal femur) can become permanently damaged due to a lack of blood supply as this part of the femur has a relatively delicate means of getting adequate circulation.