What causes the indentations to the scalp after the cortizone shots?
Anything injected into your body can potentially cause a reaction and scarring (scalp indentations). When steroids are injected into the dermis, it may cause loss of dermal fat, which could cause the indentations you are talking about. I have seen such indentations in people who have had scalp injections by doctors who believe that steroids have value for balding patients.