Past research on the sacroiliac joints was based on the premise that, 'structure governs function' and focused on the tiny internal workings of the sacroiliac joint articulations. The outcome of that research shrouded the joints with an unfathomable quality, rather than understanding. Like the kings clothes, everyone could see the sacroiliac facets were in a state of semi-dislocation, but nobody wanted to be the one to say. This is because the subject had been ‘researched’ with highly accurate imaging equipment. There are two main sacroiliac semi-dislocation theories on the back of this research commonly accepted. The ‘Nutation’ and ‘Three Pole’
Common sense went out of the window. When you stop to think, it is highly unlikely that whoever or whatever it was that designed the human body and mind would be stumped over the articulation of the sacroiliac joints. When you understand how the sacroiliac joints really articulate, you realize it is a very cleverly designed simple joint.
Function Governs Structure
Back in 2004 John Bayliss worked out how the sacroiliac joints articulate during walking, without semi-dislocation. To achieve this, he had to dismiss all that he had been taught at Osteopathic college and previously read on the subject and looked at the joint without prejudice.
Thanks to John Bayliss’s work, we can now categorically say that the iliac facets are: A set of elongated contoured facets, divided by a mid rail of which the upper facets are weight bearing and the lower facets are leg guiders.
The sacroiliac joints are cleverly designed and in keeping with other parts of the body, they have more than one function. These additional functions include the accommodation of the hips, pelvic side-shift, bi-lateral weight bearing and non-weight bearing whilst aiding the articulation of the spinal joints. To understand how all these aspects fitted together John Bayliss had to think from the point of view of ‘function governs structure’.
How the sacroiliac joints work is explained and illustrated in detail in his book ‘Advanced Osteopathic Technique’