Pelvis

Description

Anterior abdominal contents taper into a female bony pelvis formed by the paired os coxae (ilium, ischium, and pubis) articulating with the sacrum and coccyx, with the iliac crests flaring laterally and the pubic bodies meeting at the pubic symphysis in the midline. Within the pelvic brim, the large intestine frames the field from the ascending colon to the transverse and descending colon, continuing into the proximal sigmoid colon as it descends toward the lesser pelvis. Inferiorly, the femoral heads seat in the acetabula and the proximal femora extend distally from the hip joints. Nerves and vessels course along the pelvic sidewalls adjacent to the visceral compartment. Female pelvic morphology matters in ways that go beyond bony landmarks. The wider pelvic inlet and broader subpubic angle influence engagement and descent of the fetal head, so correlating the sacral promontory, arcuate line, and pubic symphysis with the pelvic cavity becomes practical anatomy for obstetrics. In pelvic and colorectal surgery, the sigmoid colon’s approach to the lesser pelvis and its relationship to the urinary bladder and uterus (when present) guide dissection planes, while the internal iliac vessels and lumbosacral plexus remain vulnerable during lymphadenectomy, endometriosis excision, and complex pelvic fracture fixation. A tight space. Common use cases include obstetrics and gynecology teaching on pelvic diameters, pelvic floor relationships, and hysterectomy orientation, as well as general surgery and colorectal modules explaining sigmoid volvulus, diverticular disease, and low anterior resection anatomy. Medical publishers also rely on this kind of integrated pelvis, bowel, and bladder view for patient education on pelvic organ prolapse and post-traumatic pelvic pain. Anatomical accuracy verified by SciePro's Medical Advisory Board.