Becoming a yoga teacher and becoming a yoga therapist is not the same thing.  You will become a yoga teacher (via yoga teacher training) first before you can move on to yoga therapy.  The requirement to enroll in our yoga

Yoga therapy is difficult to define, in part because of the breadth and depth of the tradition itself, and because, like Yoga, the discipline can be approached in so many different ways. Nonetheless, for Yoga therapy to be better understood