Pelvis

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Bone: Pelvis

Gray's	subject #57 236
Dorlands/Elsevier	p_10/12623123

The pelvis (pl. pelvises or pelves) is the bony structure located at the base of the spine (properly known as the caudal end). The pelvis incorporates the socket portion of the hip joint for each leg (in bipeds) or hind leg (in quadrupeds). It forms the lower limb (or hind-limb) girdle of the skeleton.

1 Components
2 Function
3 Additional images
4 See also
5 References
6 External links

[edit] Components

The pelvis is formed of three bones: the ilium, ischium and pubis. These three bones fuse together with age and are collectively known as the os coxae, or the innominate bone.

The pelvis is joined to the sacrum bone by ligaments (the sacroiliac joint), and the hip bones nest in specially shaped sockets (the acetabulum) on each side.

The upper edge of the ilium is known as the iliac crest.

The place at the front of the pelvis where both pubis bones join together is called the symphisis pubica. This is normally a very inflexible joint, but it softens and becomes more flexible during late pregnancy, allowing it to expand during labor for the baby's head to pass through.

[edit] Function

The pelvis protects the digestive and reproductive organs in the lower part of the body, and many large nerves and blood vessels pass through it to supply the legs. It is also an important load-bearing part of the skeletal system. It also provides a connection between the axial skeleton and the hind limbs that is the legs. The hind limb consits of several bones such as the femur, tibia, fibula, tarsus, metatarsus and phalanges. The femur is the largest bone in the human body. Its lower end articulates with the tibia to form a hinge joint at the knee. The fibula is a shorter and smaller bone. Both the tibia and fibula form joints with the tarsus at the ankle.

[edit] Additional images

Radiograph of a healthy human hip joint	Median sagittal section of pelvis.	Articulations of pelvis. Anterior view.	Articulations of pelvis. Posterior view.
Left hip-joint, opened by removing the floor of the acetabulum from within the pelvis.