From the NYT coverage of the "trauma":

Although a rectal exam is part of the routine E.R. evaluation, this patient clearly refused. His life was not in danger. He did not have any signs of abdominal trauma. He had full range of motion and movement of all four extremities. A reasonable analysis of his situation could have been obtained without checking for “rectal tone.”

One wonders whether the whole holding-down-and-sedating part might have been avoided if the ER doc took 90 seconds to explain why the procedure was important, and if the patient refused for whatever reason, what the consequences would be. Perhaps the attending was really an alien. You know they just can't get enough of those anal probes.