「The lesser pelvis (or "true pelvis") is the space enclosed by the pelvic girdle and below the pelvic brim: between the pelvic inlet and the pelvic floor. This cavity is a short, curved canal, deeper on its posterior than on its anterior wall. Some consider this region to be the entirety of the pelvic cavity. Others define the pelvic cavity as the larger space including the greater pelvis, just above the pelvic inlet.
The lesser pelvis is bounded in front and below by the pubic symphysis and the superior rami of the pubes; above and behind, by the sacrum and coccyx; and laterally, by a broad, smooth, quadrangular area of bone, corresponding to the inner surfaces of the body and superior ramus of the ischium, and the part of the ilium below the arcuate line.」
