The femur or thigh bone is the longest, most voluminous, and strongest bone of the mammalian bodies. It forms part of the hip and part of the knee.
The word femur is Latin for thigh. In strict usage, femur bone is more proper than femur, as femur refers to thigh, and femur bone refers to the bone within it. The name of the bone itself comes from os femoris, although in modern medical usage the term femur is most often applied to the bone and not the thigh. In medical Latin its genitive is always femoris, but in classical Latin its genitive is often feminis, and should not be confused with case forms of femina, which means woman.
Fractures
Femur bone fractures, on occasion, are liable to cause permanent disability because the thigh muscles pull the fragments so they overlap, and the fragments re-unite incorrectly. To avoid this, femur fracture patients should be put into traction to keep the fragments pulled into proper alignment. With modern medical procedures, such as the insertion of rods and screws by way of surgery (known as Antegrade [through the hip] or Retrograde [through the knee] femoral rodding.) Those suffering from femur fractures can now generally expect to make a full recovery, though one that generally takes 3 to 6 months due to the bone's size. Patients should not put weight on the leg without permission from an orthopedic surgeon since this can delay the healing process. The thigh is generally not put in a cast since the surgical hardware does the job of straightening the bone and holding the fracture together while it heals. Permanent complications with this procedure include the risk of intra-articular sepsis, arthritis and knee stiffness. After the bone is healed, there is no further need for the hardware but, while it is left in some patients permanently, those who lead an active lifestyle may experience discomfort where the hardware projects into the leg muscle and, in such cases, the hardware can be removed, most commonly by means of out-patient surgery.
Hip fracture
If bone is weakened, the proximal end of the femur bone near the hip joint is prone to fragility fracture. Most at risk are European descent, post-menopausal women, and osteoporosis severely increases this risk. Out of all the bones in the skeleton, the femur takes the longest to heal. This bone is the longest and strongest bone in the human body. When the average human being jumps, this bone withstands a force of half a ton just a testament to its strength.
Intercondylar Fossa
The intercondylar fossa is present between the condyles at the distal end of the femur. In addition to the intercondylar eminence on the tibial plateau, there is both an anterior and posterior intercondylar fossa (area), the sites of anterior cruciate and posterior cruciate ligament attachment, respectively.
In other animals
Parallel structures by the same name exist in other complex animals, such as the bone inside a ham or a leg of lamb. The name femur is also given to the most proximal full-length jointed segment of an arthropod's leg.