Rib breaks are really common injury in chameleons. They result from being picked up wrong.
Here’s an interesting specimen with lots of rib breaks in various stages of healing.
The proper way to pick up a chameleon is to let them step onto your hand.
Just to add to this, I see more and more people wanting chameleons, but I’d strongly advise against it for anyone who isn’t a very experienced reptile keeper. They are extremely difficult to keep happy and healthy, they’re very time consuming and vets know so little about them that they often die young with no real explanation. I’ve had dozens of different species of reptile in my care and I’d say that chameleons are the most difficult. If you’re experienced enough and are going to take one on, make sure they are a rescue and that you’re not supporting the breeding of exotic animals.
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