What is the ruling on uncovering the forearms—from the elbow to the palms—during the study and practice of medicine in Germany, for health reasons, given the impossibility of covering them?

It is not permissible for a woman to expose her forearm in front of non-mahram men, because the forearm—excluding the palm—is part of the awrah (private parts) that is unanimously agreed upon as obligatory to cover. Studying or working is not an excuse to commit this forbidden act. Ibn Hazm said: "They (the scholars) agreed that the hair of a free woman and her body, except for her face and hands, are awrah. They differed regarding the face and hands, including their nails, as to whether they are awrah or not."