I don't remember any mention of quadratus lumborum in any traditional yogic text. (sequencewiz.org)
Hello, maybe i am wrong but on picture with forearm / wrist muscles it shows that flexors and pronator quadratus work mainly in hanging.Which way will activate also more extensor muscles? (placeofpersistence.com)
Pollicis refers to the thumb, so this muscle helps to bend the thumb, and the pronator quadratus helps to turn the palms down (pronation of the forearm). (all-about-arm-exercises.com)