Pelvis
The pelvis is a basin-shaped structure formed by the two hip bones (os coxae), sacrum, and coccyx. It supports the weight of the upper body, protects pelvic organs, and provides attachment for lower limb and trunk muscles.
Key Features
Articulations
- •Hip joint (acetabulum with femoral head) - ball and socket
- •Sacroiliac joint (ilium with sacrum) - synovial/fibrous
- •Pubic symphysis (pubic bones) - secondary cartilaginous
Muscle Attachments
Clinical Relevance
Pelvic fractures can be life-threatening due to blood loss. The pelvis differs between males and females (female wider for childbirth). Sacroiliac joint dysfunction causes low back pain. Hip joint pathology affects the acetabulum.
Pelvis FAQs
Common questions about this bone
The pelvis consists of two hip bones (os coxae), the sacrum, and the coccyx. Each hip bone is formed by the fusion of three bones: ilium, ischium, and pubis, which meet at the acetabulum.
The female pelvis is generally wider and shallower with a larger pelvic outlet for childbirth. The male pelvis is narrower and deeper with a heart-shaped inlet. The subpubic angle is wider in females (>80°).
The ischial tuberosity is the thick, rough projection of the ischium that you sit on. It provides attachment for the hamstring muscles and adductor magnus. It's commonly called the 'sit bone.'
The greater sciatic foramen transmits the piriformis muscle, sciatic nerve, superior and inferior gluteal vessels and nerves, pudendal nerve and internal pudendal vessels, posterior femoral cutaneous nerve, and nerve to obturator internus.