I don't remember any mention of quadratus lumborum in any traditional yogic text. (sequencewiz.org)
A good example was a first rib subluxation I repeatedly experienced during my third pregnancy when trying to do a lower level quadratus lumborum exercise during my third trimester — the scapula and right arm aching that I experienced was no fun. (hab-it.com)
I strongly believe that much of this is due to the patterning of the way the body recruits the glutes, hamstrings and quadratus lumborum sequentially for speed. (blog.trainheroic.com)