A bony structure located at the bottom of the spine. The human sacrum forms the back part of the pelvis, is roughly triangular in shape, consists of five united vertebrae, and from its solidity it is well adapted to serve as the keystone of the pelvic arch.

Pelvic Bone, Male

A bony structure located at the bottom of the spine. The human sacrum forms the back part of the pelvis,…

Diagram showing the position of the pelvic and thigh bones in back view in the male and female.

Position of the Pelvic and Thigh Bones in the Male and Female

Diagram showing the position of the pelvic and thigh bones in back view in the male and female.

The Os Innominatum, or nameless bone, so called from bearing no resemblance to any known object, is a large irregular shaped bone, which, with its fellow of opposite side, forms the sides and front wall of the pelvic cavity. Labels: R, O, crest of ilium, just below O is seen the anterior superior spinous process; J, tuberosity of ischium; t, part of pubes, between J and T is seen the thyroid foramen: H, acetabulum, below H is seen end of ubic bone which, with its fellow of opposite side, forms the symphysis pubis.

Part of the Human Pelvic Bone

The Os Innominatum, or nameless bone, so called from bearing no resemblance to any known object, is…

The diameters of the pelvic inlet in the female.

Pelvic Inlet

The diameters of the pelvic inlet in the female.

The diameters of the pelvic outlet in the female.

Pelvic Outlet

The diameters of the pelvic outlet in the female.

"Fig 56 - Axial skeleton, minus the skull, of an owl, Asio wilsonianus, life size; from nature by Dr. R.W. Shufeldt, USA.at, atlas; ax,axis; cv, cervical vertebrae; c, c', cervical ribs, or free pleurapophyses; dv, dorsal vertebrae, excepting the last one, which joins the sacrum; R, two of the six true ribs (pleurapophyses), whereof sr is sacral; u, one of the five uncinate processes or epipleura; cr, two of the six sternal ribs(haemapophyses), whereof the sixth floats; p, pelvic or sacral region of the spine, comprehending one dorsal, and several lumbar, sacral proper, and urosacral vertebrae; I ilium; Is, ischium; P pubis; a, acetabulum; in, ischio-iliac foremen; o, obturator foramen; clv, caudal or coccygeal vertebrae, whereof py is the pygostyle; s, scapula; ohs, os humero-scapulare; cl, clavicle; C, coracoid; S, sternum." Elliot Coues, 1884

Axial Skeleton

"Fig 56 - Axial skeleton, minus the skull, of an owl, Asio wilsonianus, life size; from nature by Dr.…