Can you explain some of the reasons why women seem to have more difficulty with the sacroiliac than men.
Anatomical differences between the sexes is a factor in sacroiliac and piriformis syndromes. The female sacrum connects two vertebrae to the ilium and the male sacrum has three. The average female sacrum is slightly wider and shorter, because of the birth canal, than the more narrow, longer male sacrum. Many refer to the sacrum as the “keystone” of the body. This reference comes from a term used in construction to describe the last stone to go in place when building an arch. If the “keystone” is out of place, the arch will collapse.