Michelangelo and medicine

Dr Strauss and Dr Marzo-Ortega (October 2002 JRSM¹) and indeed the other authors they cite, do not refer to two other aspects of medical interest in Michelangelo's David. The first is the very large right hand which is quite disproportionate to the size of the rest of the statue, although, as far as I am aware, anatomically normal. The second feature is the depiction of David with his sling over his left shoulder with a stone in his right hand. This strongly implies that the subject was left-handed. The only commentary I have found on this point is that the stone from which the statue was carved was difficult to work, and indeed it had already been worked on by others before Michelangelo used it. While this may have affected the way the sculpture was made it does not seem entirely convincing that it necessitated making a left-handed subject.