Structural groups of muscles largely determine functional groups—that is, the structural location of a muscle largely determines its mover function.
Five Muscles of Sacroiliac Stabilization – Part 3 – Hamstrings
The connection between the hamstrings and the sacroiliac joint is through what is known as the superficial back line myofascial meridian/anatomy train. If the hamstrings are tight, their tension pulling force will be exerted through the sacrotuberous ligament and onto the sacrum.
Other Unusual Suspects
Semispinalis capitis, pectineus, & vastus lateralis are unusual suspect muscles, often overlooked by manual therapists, that can cause pain and dysfunction.
