What is the femur?
Femur is the medical term for the thigh bone. It is a tubular bone and is divided into different sections:
At the upper end, the spherical femoral head (caput femoris) sits slightly angled on a long neck (collum femoris), the femoral neck. Together with the socket of the pelvic bone, the head forms the hip joint, which enables the leg to move. Depending on age and gender, the femoral neck forms an angle (collum-diaphyseal angle) with the shaft that varies in size: in newborns and infants, the angle is up to 143 degrees. With increasing age, the angle becomes smaller and in adults it reaches 120 to 130 degrees.
The femoral neck becomes thicker from top to bottom and is flattened from front to back. This shape makes it possible to carry heavy loads – the actual task of the femoral neck. It is comparable to the boom of a crane, which carries the load of the body. The bone beams on the inside then correspond to the struts of a crane. With increasing age, some of these struts disappear, which increases the risk of suffering a femoral neck fracture in the event of a fall.
At the very top of the shaft there is a roundish bony tuberosity on the outside and inside: on the outside is the greater trochanter and on the inside the lesser trochanter. Muscles attach to both (like the hip flexor). The greater trochanter is clearly palpable from the outside (in contrast to the lesser trochanter).
At the lower end, the femur is widened into two rolls that are covered with cartilage (condylus medialis and lateralis). Together with the tibia, they form the knee joint.
What is the function of the femur?
The femur is the strongest and longest bone in the body. Through its involvement in the hip joint and knee joint, the femur enables the leg to move in relation to the trunk and the lower leg in relation to the thigh.
Where is the femur located?
The femur (thigh bone) connects the trunk to the lower leg. It is articulated to both the pelvis and the tibia.
What problems can the femur cause?
The femur can break at any point. Such fractures occur particularly frequently in the area of the femoral neck (femoral neck fracture) – especially in older people.
The external angle between the femur and tibia at the knee joint is normally around 176 degrees. It is reduced in knock-knees and increased in bowlegs.
