Sacroiliac Joint Hypomobility Definition

The sacroiliac joint lies next to the spine and connects the sacrum with the pelvis. This joint can be a source of pain, usually due to an alteration in normal joint motion. Sacroiliac joint hypomobility, or fixation, refers to reduced movement of the joint. Pain is typically felt on one side of the low back or buttocks, and can radiate down the leg.