what does the ql muscle do
Anatomy texts typically identify the quadratus lumborum (QL) as a muscle that is a prime mover in lateral trunk flexion and hip-hiking, as an assist with trunk extension when acting bilaterally, and stabilizer of the lower ribs against the diaphragm. patient presenting with chronic low back pain is asked to side bend laterally, sitting in a chair with the pelvis stabilized. The contralateral QL is expected to function as an eccentric guy wire to side bend away from the active QL, and then function concentrically to return the trunk to the upright position.