I've never tried it on Dinos but I don't see why it would be any different on a horse than a dino. Just cut where you want to move, then use super glue (zap a gap is the best) and baking soda to hold. Apply super glue, hold piece in place, then sprinkle on some baking soda and it hardens the super glue immediately.
It can be sanded and then painted (after prepping/priming) too. Whatever you do - do not use the hot water or hair dryer method! Eventually the model will go back to the original shape - the plastic will remember the position it was in. This also makes very rubbery and unrealistic joints.
Your best bet is to cut the section and drill into either side, inserting a sturdy wire and gluing with the supersoda combination. However I'm lazy and rarely use a wire
Usually just for necks on horses, where major support is needed. You can make that decision whether you need the wire or not based on what you're changing.