Gross Anatomy of Pelvis and Perineum

Gross Anatomy of Pelvis and Perineum

• The pelvis is the inferior part of the trunk.
• It includes the pelvic girdle and perineum.
• The pelvic girdle supports the reproductive and urinary organs.
• The hip bone (coxal bone) forms the pelvic girdle, acting as an attachment point for each lower limb.
• The hip bone is connected to the sacrum through sacroiliac joints, and to each other anteriorly by the pubic symphysis.
• The bony pelvis is composed of two hip bones, the sacrum, and the coccyx.
• Unlike the pectoral girdle, the pelvic bones are firmly connected to provide stability for weight bearing.
• The pelvic girdle transfers weight from the vertebral column to the lower limbs.

Hip Bone

• The hip bone is also known as the coxal bone.
• It's formed by three separate bones (ilium, ischium, and pubis) that fuse during late teenage years.
• These bones form the pelvic girdle of the lateral and anterior aspects of the pelvis.

Ilium

• The curved superior margin is the iliac crest.
• Its rounded anterior terminations are the anterior superior and inferior iliac spines.
• The iliac fossa is a shallow depression on its anterior surface.
• The sacroiliac joint connects it to the sacrum.
• The arcuate line is the boundary between upper and lower parts of the ilium.
• The greater sciatic notch is a U-shaped indentation.

Ischium

• The ischium forms the posterolateral portion of the hip bone.
• Its roughened area inferiorly is the ischial tuberosity.
• The lesser sciatic notch is found above this.

Pubis

• The pubis forms the anterior portion of the hip bone.
• The pubic body is the enlarged medial portion.
• The pubic tubercle is a small bump on the superior aspect of the pubic body.
• The pubic symphysis connects the pubic bones.
• The subpubic angle is the inverted V-shape connecting the pubic rami.

Pelvis

• The pelvis is formed by the two hip bones, the sacrum, and the coccyx.
• The bones of the pelvis are firmly connected to each other to provide stability and allow the transfer of weight.

Pelvic Floor

• The pelvic diaphragm is the floor composed of two muscle pairs (levator ani and coccygeus).
• The muscles support pelvic organs and prevent prolapse.

Perineum

• The perineum is the area between the thighs from pubic symphysis anteriorly to coccyx posteriorly.
• It contains external genitalia and anus.
• The perineum is divided into urogenital and anal triangles.

Pelvic Organs

• The pelvic area contains the urinary bladder and parts of the digestive organs.
• The uterus, vagina, and ovaries are located within female pelvis.
• The rectum and prostate gland are located within male pelvis, behind the bladder.

This quiz explores the anatomical structures of the pelvis and perineum, focusing on the pelvic girdle and hip bones. Understand the relationships between the components, including the sacrum and coccyx, and their functions in supporting lower body functions. Dive into the details of the ilium, ischium, and pubis for a comprehensive understanding.