The Pelvic Girdle and Pelvis

The Pelvic Girdle

Also called hip girdle; formed by 2 hip bones (coxal bones, or os coxae) and sacrum

Function of Pelvic Girdle

Attaches lower limbs to axial skeleton with strong ligaments; transmits weight of upper body to lower limbs; supports pelvic organs

Pelvic Girdle Mobility

Less mobility but more stability than shoulder joint

Coxal Bone Composition

Formed by three fused bones: ilium, ischium, and pubis

Acetabulum

Deep socket formed at point of fusion; receives head of femur

Ilium

Superior region of hip bone

Ilium Structure

Consists of body and winglike ala

Iliac Crests

Thickened superior margin of ala

Iliac Crest Ends

Ends at anterior superior iliac spine and posterior superior iliac spine

Greater Sciatic Notch

Passage for sciatic nerve

Auricular Surface

Articulates with sacrum

Arcuate Line

Defines pelvic brim

Ischium

Posteroinferior part of hip bone

Ischial Spine

One of three important markings of ischium

Lesser Sciatic Notch

One of three important markings of ischium

Ischial Tuberosity

One of three important markings of ischium

Pubis

V

Obturator Foramen

Large opening formed by rami and body

Pubic Symphysis

Where pubic bones join

Pubic Arch (Subpubic Angle)

Formed by rami; main difference between male and female pelves

Pelvis

Formed by hip bones, sacrum, and coccyx

Female Pelvis

Wider, shallower, lighter, and rounder than male pelvis; adapted for childbearing

Pelvic Brim (Pelvic Inlet)

Continuous oval ridge running from pubic crest through arcuate line and sacral promontory

Female vs Male Pelvis

Female pelvis is broader, with larger subpubic angle, rounder pelvic brim, and wider, shallower lesser pelvic cavity