The Principles of Osteopathic Technique
A. S. Hollis, D.O.
1914

FIGURE 69
 

Fig. I.  Diagram representing the hammock-like method of suspension of the Sacrum between the two Innominates.
Fig. II.  Diagram representing the full range of movement occurring between the Sacrum and the Innominates.
Fig. III.  Diagram representing the mechanism of the movement in the sacro-iliac joint looking at it from in front.