How long has those legs been like that? Has he been treated for metabolic bone disease?
Several people have commented that your young chameleon looks like he has severe metabolic bone disease, based on the severely bent or broken legs. If your vet said that a lot of chameleons are like that I would fire that vet and find one that had an inkling of how to treat reptiles. Just because a lot of chameleons suffer from this disease doesn't mean it is normal. It is a serious, painful and life threatening disease and should be treated. Broken bones are not without pain regardless of the cause.
I suggest you read the article at the top of the Health section on metabolic bone disease.
You need to get this animal to a vet that has some understanding of treating reptiles.