Appendicular Skeleton - Bones of the Pelvic Girdle

arcuate line

a ridge of bone that runs inferiorly and anteriorly from the auricular surface of the ilium; visible in the medial view

lesser sciatic notch

a small notch located inferior to the ischial spine

pubic arch of male pelvis

angle is more acute

bone thickness of male pelvis

bones are heavier and thicker, markings are more prominent

bone thickness of female pelvis

bones are lighter, thinner, smoother

pubic arch of female pelvis

broader angel, more rounded

greater sciatic notch

deep notch located superior to the ischiac spine; allows the sciatic nerve to enter the thigh; upper border and deep part of lower border belong to ilium; lower border, nearest ischial spine, belongs to ischium

acetabulum

deep socket where the ilium, ischium, and pubis fuse; receives the head of the thigh bone; visible from the lateral view

obturator foramen

foramen enclosed by a bar of bone formed by the rami of the pubis and ischium; allows blood vessels and nerves to pass

pubic arch

formed by the convergence of the inferior rami of the ischium and pubis on either side, below the pubic symphysis

inferior pubic ramus

inferior extension of the body of the pubis; articulates with the ischium

sacroiliac joint

joint in between the sacrum and the ilium; joined by strong ligaments

ischial spine

located superior to the ischial tuberosity and projects medially into the pelvic cavity

symphysis pubis

midline cartilaginous joint uniting the superior rami of the left and right pubic bones

sacrum of male pelvis

narrow, longer, sacral promontory projects anteriorly

ischial tuberosity

rough projection that receives the weight of our body when we are sitting; most visible on lateral and posterior views

iliac fossa

shallow depression below the iliac crest; forms the internal surface of the ilium; visible in anterior & medial views

pelvis

structure formed by the ossa coxae, sacrum, and coccyx

superior pubic ramus

superior extension of the body of the pubis; process of bone extending between body of pubis and acetabulum

iliac crest

thick superior margin of bone (hands on hip)

structure of male pelvis

tilted less forward; adapted for support of a male's heavier build and stronger muscles; cavity of the true pelvis is narrow and deep

structure of female pelvis

titled forward; adapted for childbearing; true pelvis defines the birth canal; cavity of the true pelvis is broad, shallow, and has a greater capacity

sacrum of female pelvis

wider, shorter, sacrum is less curved

os coxa

(2, pelvic girdle) form the hip; large, heavy, irregular bones; attach to the axial skeleton; ability to bear weight is more important than flexibility (more so than in pectoral girdle) fused bones: ilium, ischium, pubis Markings: acetabulum, obturator foramen

ischium

(os coxa) "sit down bone" parts: ischial tuberosity, ischial spine, lesser sciatic notch

pubis

(os coxa) 2 pubic bones meet at pubic crest; inferior and anterior part of the os coxa parts: superior pubic ramus, inferior pubic ramus, symphysis pubis, pubic arch

ilium

(os coxa) large bone; "hands on hip" parts: iliac crest, iliac fossa, arcuate line, sacroiliac joint, greater sciatic notch

bones in the pelvic girdle

2 os coxa (and the sacrum)