The pelvis is made of 4 bones
The pelvis is made of 4 bones: the two hip bones, the sacrum at the back in the middle, and the coccyx below it. Each hip bone forms from three bones, the ilium, ischium and pubis, that fuse into one during growth, and the cup where the three meet, the acetabulum, holds the head of the femur. The two hip bones meet at the front at the pubic symphysis and join the sacrum at the back at the sacroiliac joints.
Frequently asked questions
How many bones are counted in the pelvis?
Four in the adult. Counted separately, the ilium, ischium and pubis of each side would make six, plus the sacrum and coccyx, but in the adult the three on each side have fused into a single hip bone.
Which parts of the pelvis can be felt?
The curved rim you feel at the sides of the waist is the iliac crest of the ilium, and the bones you sit on are the ischial tuberosities of the ischium.
How do male and female pelvises differ?
They have the same bones. The female pelvis is generally wider and shallower with a rounder inner opening, while the male pelvis is narrower and deeper.
The bones counted
Related counts
Other bone counts
- Bones in the human body
- Bones of the skull
- Cervical vertebrae
- Thoracic vertebrae
- Lumbar vertebrae
- Number of ribs
- Bones of the arm
- Bones of the hand
- Carpal bones
- Bones of the foot
- Tarsal bones
- Phalanges of the fingers and toes
Skeleton
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