Sacroiliac joint anatomy in 3D
The sacroiliac joint is where the sacrum at the base of the spine meets the ilium of each hip bone, one on either side at the back of the pelvis. The uneven joint surfaces of the two bones interlock and very strong ligaments bind them together. The weight of the upper body passes through these joints into the pelvis and legs.
Frequently asked questions
Which bones form the sacroiliac joint?
The sacroiliac joint is formed by the sacrum and the hip bone.
What type of joint is the sacroiliac joint?
It combines a synovial joint at the front with a fibrous connection of ligaments behind.
What movements happen at the sacroiliac joint?
It moves very little, allowing only slight tilting and gliding. Its main job is to carry and transfer weight rather than to produce movement.
Bones of the sacroiliac joint
Other joints
- Shoulder joint
- Acromioclavicular joint
- Elbow joint
- Radioulnar joints
- Wrist joint
- Thumb carpometacarpal joint
- Hip joint
- Knee joint
- Ankle joint
- Subtalar joint
- Temporomandibular joint
- Atlanto-occipital joint
- Atlanto-axial joint
- Intervertebral joints
- Costovertebral joints
Skeleton
Read more
Related reading
- Sarcopenia: what to measure, and what to do, when muscle and strength decline
- What getting up from a chair says about how your body is ageing
- Why ageing bone marrow turns to fat, and a PEMF study in mice
- PEMF and whole-body vibration: two rhythms that reach the body
- Myokines: the signals working muscle sends to the body
- Ageing parents: the changes families notice first
Once the 3D model loads you can turn it and select each part.