Bony Pelvis Anatomy

Bony Pelvis

• The pelvis is a basin-shaped structure composed of four bones:
  • Two innominate bones (hip bones)
  • Sacrum
  • Coccyx
• The pelvis serves as a base of support for the spine and a point of attachment for muscles

Innominate Bones

• Each innominate bone is formed by the fusion of three bones:
  • Ilium
  • Ischium
  • Pubis
• The innominate bones form the acetabulum, which articulates with the femoral head to form the hip joint

Sacrum and Coccyx

• The sacrum is a triangular bone formed by the fusion of five vertebrae
• The coccyx, or tailbone, is a small bony structure located at the bottom of the sacrum

Pelvic Cavity

• The pelvic cavity is a space within the pelvis that contains:
  • Reproductive organs
  • Urinary bladder
  • Rectum
  • Blood vessels
  • Nerves

Perineum

• The perineum is the region between the anus and genitals
• The perineal body is a central tendon that serves as an attachment point for muscles

Perineal Muscles

• The perineal muscles include:
  • External anal sphincter
  • Bulbospongiosus
  • Ischiocavernosus
  • Superficial transverse perineal muscle
  • Deep transverse perineal muscle

Clinical Significance

• Knowledge of pelvic and perineal anatomy is essential for understanding various medical conditions, such as:
  • Pelvic fractures
  • Prostate cancer
  • Vaginal childbirth
  • Anal incontinence

Bony Pelvis

• Composed of four fused bones: two innominate bones, sacrum, and coccyx
• Serves as a base of support for the spine and a point of attachment for muscles

Innominate Bones

• Formed by the fusion of three bones: ilium, ischium, and pubis
• Form the acetabulum, which articulates with the femoral head to form the hip joint

Sacrum and Coccyx

• Sacrum: a triangular bone formed by the fusion of five vertebrae
• Coccyx (tailbone): a small bony structure located at the bottom of the sacrum

Pelvic Cavity

• A space within the pelvis that contains reproductive organs, urinary bladder, rectum, blood vessels, and nerves

Perineum

• The region between the anus and genitals
• Perineal body: a central tendon that serves as an attachment point for muscles

Perineal Muscles

• Include: external anal sphincter, bulbospongiosus, ischiocavernosus, superficial transverse perineal muscle, and deep transverse perineal muscle

Clinical Significance

• Knowledge of pelvic and perineal anatomy is essential for understanding pelvic fractures, prostate cancer, vaginal childbirth, and anal incontinence