Femur - The Longest And Strongest Bone, Structure and Conditions
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Femur : The Longest And Strongest Bone

Dr.Surya Rao Poodipeddi profile Authored by Dr.Surya Rao Poodipeddi on 8 May 2014 - 12:57.

Of all the bones in the human body the femur, also called the thighbone, is the longest and strongest bone.

In a fully grownup adult it measures around 18 inches in length. They are two in number one each for the corresponding thigh and hence called the thighbone. It is almost cylindrical through the greater portion of its length.

In an erect posture the femur is not vertical and is separated from its counterpart for a considerable interval corresponding to the width of the pelvis at whose ends each femur forms the hip joint. It proceeds gradually downwards and inwards in an inclining fashion and the lower end meets with the other femur at the level of the knee. This facilitates the center of gravity to pass through the knee joints with equal balance.

The inclination of the femur downwards and inwards varies in different persons and is greater in females than in the males because of greater width of the pelvis, which accounts for larger area in the pelvic cavity to accommodate the growing fetus in pregnant ladies.

Bone structure: Like any other long bones, the femur has a body and two extremities. The body or shaft of the femur is a little broader at the top and less broader at the center. At its lower end the femur is slightly flat from front to the back. It is slightly arched with its convexity in front and concavity behind, where a prominent longitudinal ridge strengthens it.

The upper extremity has a neck and a head. The head fits into the acetabulum of the hipbone to form the hip joint, which is a ball and socket joint to facilitate movements in all directions. The lower extremity is flat and joins the upper end of the leg bone called the tibia to form the knee joint, which can move only backwards.

The femur has a rich blood supply and is surrounded by strong muscles and tendons to perform various movements in the lower limb mainly at the hip joint.

The hollow canal in the full length of the femoral shaft has bone marrow, which is responsible for the manufacture of the blood cells whenever they are dead as an act of replacement with new cells. 

Conditions of the femur: Several conditions affect the femur bone. Few of the important conditions:

  • Congenital conditions like congenital psuedoarthrosis and congenital absence of the femur.
  • Osteogenesis imperfecta is another condition, which may affect a child. Metabolic conditions like rickets and scurvy may involve the femur.
  • Cancer of the femur is not uncommon.
  • Fractures and dislocations resulting from trauma. Fracture neck of the femur is the commonest condition affecting the elderly age group, if osteoporotic.
  • Inflammatory conditions like osteoarthritis and rheumatoid arthritis of the hip and knee joints, where the upper and lower ends of the femur are involved in the formation of hip and knee joints.
  • Osteomylitis is a condition, which can affect the femur and its surrounding areas due to germs traveling from blood from nearby areas of infection. If present, this is a nasty problem where small pieces of bone come out with the pus which we call it as sequestrum. Doctors treating osteomylitis mainly rely on antibiotics. Some stubborn infections may need sequestrectomy operation.


*Disclaimer: This is not medical advice. The content is for educational purposes only. Please contact your doctor for any health care issues.