sacrotuberous

It is bounded medially by the Sphincter ani externus and the anal fascia; laterally, by the tuberosity of the ischium and the obturator fascia; anteriorly, by the fascia of Colles covering the Transversus perinæi superficialis, and by the inferior fascia of the urogenital diaphragm; posteriorly, by the Glutæus maximus and the sacrotuberous ligament.

IV. Myology. 1F. The Muscles and Fasciæ of the Perineum 1918

Its deep boundaries are—in front, the pubic arch and the arcuate ligament of the pubis; behind, the tip of the coccyx; and on either side the inferior rami of the pubis and ischium, and the sacrotuberous ligament.

IV. Myology. 1F. The Muscles and Fasciæ of the Perineum 1918

The borders of the coccyx are narrow, and give attachment on either side to the sacrotuberous and sacrospinous ligaments, to the Coccygeus in front of the ligaments, and to the Glutæus maximus behind them.

II. Osteology. 3a. 4. The Sacral and Coccygeal Vertebræ 1918

Below, it is bounded by a sharp ridge which gives attachment to a falciform prolongation of the sacrotuberous ligament, and, more anteriorly, gives origin to the Transversus perinæi and Ischiocavernosus.

II. Osteology. 6c. The Bones of the Lower Extremity. 1. The Hip Bone 1918

Below, the obturator fascia is attached to the falciform process of the sacrotuberous ligament and to the pubic arch, where it becomes continuous with the superior fascia of the urogenital diaphragm.

IV. Myology. 6e. The Muscles and Fasciæ of the Pelvis 1918

The transverse tubercles of the first sacral vertebra are large and very distinct; they, together with the transverse tubercles of the second vertebra, give attachment to the horizontal parts of the posterior sacroiliac ligaments; those of the third vertebra give attachment to the oblique fasciculi of the posterior sacroiliac ligaments; and those of the fourth and fifth to the sacrotuberous ligaments.

II. Osteology. 3a. 4. The Sacral and Coccygeal Vertebræ 1918

When the ligaments are in situ, the inferior aperture of the pelvis is lozenge-shaped, bounded, in front, by the pubic arcuate ligament and the inferior rami of the pubes and ischia; laterally, by the ischial tuberosities; and behind, by the sacrotuberous ligaments and the tip of the coccyx.

II. Osteology. 6c. 2. The Pelvis 1918

The other notches, one on either side, are formed by the sacrum and coccyx behind, the ischium in front, and the ilium above; they are called the sciatic notches; in the natural state they are converted into foramina by the sacrotuberous and sacrospinous ligaments.

II. Osteology. 6c. 2. The Pelvis 1918

The thin lower half of the lateral surface gives attachment to the sacrotuberous and sacrospinous ligaments, to some fibers of the Glutæus maximus behind, and to the Coccygeus in front.

II. Osteology. 3a. 4. The Sacral and Coccygeal Vertebræ 1918

From these loops branches run to the dorsal surface of the sacrotuberous ligament and form a second series of loops under the Glutæus maximus.

IX. Neurology. 6a. The Posterior Divisions 1918