# 6.1: The Pelvic Girdle

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## Sacrum

A continuation of the vertebral column, the sacrum is composed of five fused vertebrae. Where the sacrum meets with the fifith lumbar vertebra it is widest, decreasing in size inferiorly. The sacrum also makes up the posterior aspect of the pelvic girdle.

Base

Apex

Promontory

Ventral surface

Transverse ridges

Anterior sacral foramina

Dorsal surface

Medial sacral crest

Posterior sacral foramina

Lateral surface - Wings or ala

## Coccyx

Four very small vertebrae found at the apex of the sacrum which are fused in adults, but are often absent in archaeological specimens. The corunae are the only landmarks seen on the coccyx, which are tubercles projecting superiorly from the body of the coccyx.

Sacrum. Top anterior and Bottom posterior.

Sacrum. Lateral view.

Superior coccygeal body. Left view anterior and Right view posterior.

Inferior coccygeal elements. Left view anterior, Middle view posterior, Right view superior articulation.

Superior and Inferior coccygeal elements articulated.