 In anatomy, the hip is the bony projection of the femur
which is known as the greater trochanter, and the overlying
muscle and fat. The hip joint is the joint between the
femur and acetabulum of the pelvis and its primary function
is to support the weight of the body in both static (e.g.
standing) and dynamic (e.g. walking or running) postures.
Description of the Bones of the Hips
The hip bones are divided into 5 areas, which are:
The sacrum: This is a bone at the base of the vertebral
column that is created by the fusion of 4 vertebrae.
It attaches to the ilium on the sides. It also provides
a point of muscle attachment for back muscles.
The coccyx (also called the tail bone): This is a small
bone that attaches to the base of the sacrum. It is created
from the fusion of 4 small vertebrae.
The ilium: This is the largest area of the hip bones.
It consists of 2 large broad plates, one on each side,
which serve to support the internal organs, and to provide
attachment for muscles of the back, sides, and buttocks.
The hip joint of the femur is part of the ilium.
The ischium: The ischium consists of 2 broad curves
of bone, one on each side, which lie below the ilium,
and are attached to the pubis in the front and the ilium
in the back. The ischium serves as a place of attachment
for muscles. When a person's butt hurts from sitting
on a hard surface, it is the result of the sharp ischium
pressing on the buttocks.
The pubis: The pubis is the front-most area of the hip
bones. It attaches to the ilium on the sides and the
ischium on the bottom. It provides structural support,
and serves as a place of attachment for the muscles of
the inner thigh.
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