ANSWER:
If water cannot be touched at the place of injury and there is no bandage over the wound to wipe over it, then you must do tayammum for that skipped area to make your ghusl valid.
ANSWER:
If water cannot be touched at the place of injury and there is no bandage over the wound to wipe over it, then you must do tayammum for that skipped area to make your ghusl valid.