Most Common Reptile Injuries In Captivity?

For snakes all I can think of off the top of my head is burns from unregulated heat sources and bites from feeders left in enclosures too long. For lizards I can think of MBD from not dusting insects or not using UVB. Or missing toes and other extremities from improper sheds.

injuries to snakes listed from most commonly seen to least common as seen from my own time spent on this forum (so this is just my opinion):

unregulated heat burns, live prey bites, injuries caused by tape or other super-sticky adhesives, injuries caused by improper/unsafe decor or enclosure (e.g. injury from escaping the enclosure), stuck shed causing loss of circulation to a part of the body, torn/missing scale from a recent shed, torn scales, neurological symptoms developing from too hot environment, tooth abscess

Yeah keeping them too hot can be really bad. When,I got my first blood I was told to kept the hot side at 96 degrees. Which was against every care sheet I've seen. Maybe he died so early because of complications from that, who knows. I kept him at cooler temps

Snake Injuries. Burns, bites are rare when fed responsibly which most people do, both cases are preventable and are due to improper research.

Snake diseases RI and scale rot, you can prevent scale rot and you can lower the risk of RI (again knowledge and research plain a main part)

Lizard injuries: Burns - preventable

Lizard diseases: MBD - preventable

Those are the things we deal the most on forums.