Chameleon problem please help

Question
my boyfriends brother has a pet chameleon and has left it with us while he is on holiday but for no reason whatsoever scabbing has appeared along its spine and on its knee joints have you any idea what it could be?
i don't really know much about how the chameleon is kept apart from its a glass enclosure as my boyfriend deals with it i just know that nothing has changed habitat and care wise and they have never had any problems in the past sorry i cant give you more details.

Answer
Claire,                                                      Make sure you are misting him twice a day. Go get some reptisafe and make up a mist and get some reptile wound heal.This is by zoo med.I am sure if your pet shop don't carry it they carry something comparable. It might be stress. He will be fine if your keep him hydrated and get some medicine for his boo boos.... Good Luck, Tina