Fig. 28.

The Schroth prone exercise with activation of the iliopsoas muscle (right hip flexion). Blue arrows represent trunk elongation with caudal and cranial forces. Red arrows represent areas of muscle activation around the convexities towards the midline. Green half-moons represent areas of expansion of the concavities. Red circles represent additional corrective forces: red circles around the right lower extremity and the right upper extremity represent iliopsoas activation and shoulder traction/counter-traction, respectively, resulting in correction of the lumbar and thoracic curves