Femur
Say it: FEE-mur
The femur is the thigh bone, the longest and strongest bone in the human body, running from the hip joint down to the knee.
Also: thigh bone, femora
Definition
What is the femur?
The femur, the one bone of the thigh, is also the longest and strongest bone in the skeleton, roughly a quarter of a person's height. Its rounded head sits in the acetabulum, the cup-shaped socket on the side of the pelvis, creating the hip joint, and a narrower neck joins the head to the shaft at an angle. Just below the neck, two bony knobs, the greater and lesser trochanters, anchor powerful hip muscles, and a rough ridge down the back of the shaft, the linea aspera, gives attachment to thigh muscles. At the lower end, the medial and lateral condyles meet the tibia at the knee, while the kneecap (patella) glides over a groove on the front.
Like other long bones, the femur is a tube of compact bone around a marrow cavity, with spongy bone filling its ends. It bears the body's weight in standing and walking and acts as a lever for the muscles that move the hip and knee.
Fractures of the femoral neck, typically from falls in older people with osteoporosis, are common and serious. Vessels supplying the femoral head run along the neck, so such a break can cut off its blood and cause the bone to die (avascular necrosis). Breaking the shaft takes great force and can cause heavy bleeding.
Word parts
Where does the word “femur” come from?
- femur
- thighLatin femur
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Terms that go with it
- BoneBone is the hard, mineralized connective tissue that makes up most of the adult skeleton, and the name for each skeletal organ built from it.
- CartilageCartilage is a tough, flexible connective tissue without blood vessels that cushions joints and shapes the nose, ears and airways.
- LigamentA ligament is a band of tough, fibrous connective tissue that joins one bone to another and keeps a joint stable while letting it move.
- Skeletal muscleSkeletal muscle is the striated, voluntary muscle tissue attached to bones by tendons that moves the body, holds posture and produces heat.
- TendonA tendon is a tough cord of dense connective tissue linking a muscle to a bone, which passes on the muscle's pull to move it.
Sources
Checked against
Written for biofideX in plain words, after checking these references:
- OpenStax Anatomy and Physiology 2e, 8.4 Bones of the Lower Limb
- TeachMeAnatomy: The Femur
- NCBI MeSH: Femur
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