Anatomy of a Dragon

I've been wanting to do a quick mockup of dragon anatomy for a long time. I finally had the opportunity to put this together. I wanted to play with some ideas for how a hexapod could reasonably function. Unlike a lot of other artists I placed the wing arms in front of the walking arms. I thought this would allow for better range of motion for the wings, might be a good thing to have for flight haha. I played primarily with archosaur anatomy forms here. Obviously the wing bones are inspired by birds, however they have cartilaginous struts that extend from the metacarpals to create a more classical dragon webbed wing. The shoulder girdle/keel is fused with the scapulocoracoid of the second arm set, so the entire chest is very rigid. As such the secondary arms would have less rand of motion and this guy would run on his hind legs using his wings for balance in order to move faster along the ground and for takeoff. Also notice how much the keratin extends the claws and horns.