The intermediate ridge or pectineal line is continued to the base of the lesser trochanter and gives attachment to the pectineus; the medial ridge is lost in the intertrochanteric line; between these two a portion of the iliacus is inserted.
12.
The fossa gives origin to the Iliacus muscle and is perforated at its inner part by a nutrient canal; below this there is a smooth, rounded border, the arcuate line, which runs anterior, inferior, and medial.
13.
The external surface of the capsule is rough, covered by numerous muscles, and separated in front from the psoas major and iliacus by the iliopectineal bursa, which not infrequently communicates by a circular aperture with the cavity of the joint.
14.
It presents a large, smooth, concave surface, called the iliac fossa, which gives origin to the Iliacus and is perforated at its inner part by a nutrient canal; and below this a smooth, rounded border, the arcuate line, which runs downward, forward, and medialward.
15.
To the external lip are attached the Tensor fasci?lat? Obliquus externus abdominis, and Latissimus dorsi, and along its whole length the fascia lata; to the intermediate line the Obliquus internus abdominis; to the internal lip, the fascia iliaca, the Transversus abdominis, Quadratus lumborum, Sacrospinalis, and Iliacus.
16.
Below, it has the following attachments : posteriorly, to the whole length of the iliac crest, between the attachments of the transverse abdominal and Iliacus; between the anterior superior iliac spine and the femoral vessels it is connected to the posterior margin of the inguinal ligament, and is there continuous with the iliac fascia.
17.
It is retained in contact with the posterior wall of the abdomen by the peritoneum, which covers its anterior surface and sides, its posterior surface being connected by loose areolar tissue with the iliacus, quadratus lumborum, aponeurotic origin of transversus abdominis, and with the front of the lower and lateral part of the right kidney.
18.
It descends through the fibers of the psoas major muscle, emerging from the muscle at the lower part of its lateral border, and passes down between it and the iliacus muscle, behind the iliac fascia; it then runs beneath the inguinal ligament, into the thigh, and splits into an anterior and a posterior division.
19.
Inside the pelvis the obturator artery gives off iliac branches to the iliac fossa, which supply the bone and the Iliacus, and anastomose with the ilio-lumbar artery; a vesical branch, which runs backward to supply the bladder; and a pubic branch, which is given off from the vessel just before it leaves the pelvic cavity.
20.
Of these, the uppermost, situated at the junction of the crest and anterior border, is called the anterior superior iliac spine; its outer border gives attachment to the fascia lata, and the Tensor fasci?lat? its inner border, to the Iliacus; while its extremity affords attachment to the inguinal ligament and gives origin to the sartorius
