The pelvis is made up of 6 bones:
- 2 ilium
- 2 ischium
- 2 pubic bones
These all come together at the sacrum to form a ring shape, which also connects to the hip joint. Muscles and ligaments surround the pelvis to keep it stable as the rest of our body moves. Instead of reviewing all the muscles that act on the pelvis please see the images on the hip, back and abdominal pages.
The image on the right shows the large amount of ligaments that help keep the pelvis stable.
Even with the large amount of support, the pelvis still allows for some movement.
The motions of the pelvis include:
- Anterior pelvic tilt
- Posterior pelvic tilt
There is also a small amount of movement that occurs at the sacroiliac (SI) joint, which is the connection of the sacrum to the iliac portion of the pelvis. The SI joint can be injured during exercises like a thruster or deep squat because unnecessary forces are placed on it when midline stabilization is lost.
* Click on the image to the right to view the SI joint, and its relationship to the piriformis muscle and sciatic nerve.
Created by: Missy Albrecht DPT, CSCS, FMS
Reference: Dutton, Mark. Orthopaedic Examination, Evaluation, and Intervention. Second edition. The McGraw-Hill Companies, Inc, 2008: 1609-1658.
