That looks like a fracture to me, you need to make sure he or she is not moving around and causing it to move because that will undo the healing process. I only know how to immobilize broken human bones, so I’m not sure how I’d immobilize that, but I’d keep a reptile vet on call in case any signs of infection appear. Keep an eye out and go to the reptile vet if any of the following happens:
- bloody stool
- pus leaking from the vent
- there’s a foul odor coming from that area on your dragon
- seizures start happening (cerebrospinal infection)
- the tail starts turning black and starts shriveling up
- your beardie starts vomiting
- your beardie starts
blackbearding
Some great signs include:
- hematoma (blood pooling in the area *in a controlled manner* - blood cells bring the building blocks for new bone to be made.)
- use of hind legs (swelling will likely deactivate the nerves for a while
- movement in the tail
Take a photo every day so you can compare and show a vet if you need to.