Sacroiliac Syndrome
Sacroiliac syndrome (SI pain, SI dysfunction) - The sacroiliac joints are the paired joints between the sacrum (the triangular bone that the spine rests on) and the paired ilium (the sides of the pelvis)- hence the named “sacroiliac joint”. This joint is complex and nothing like any other joint in the body. It is variegated (irregular with many nooks and crannies) and has 2 different types of structures within it. The top part is a typical joint like a hip or knee called a diarthrodial joint and the bottom part is a fibrous joint.
This joint is blamed for the cause of pain that commonly occurs over it but it is typically an innocent bystander. Most pain in the sacroiliac joint comes from a nerve or disc in the lower back that radiates into this joint. There are rare circumstances that this joint can cause pain but again, they are rare.
