throckmorton’s sign.

Also known as the “John Thomas” sign. It was probably named after Tom Bentley Throckmorton who was a resident physician at the Philadelphia Orthopaedic Hospital and assistant physician at the Cheroku State Hospital for the insane during the early 1900′s.
It describes the spooky medical phenomenon that on a male pelvic XR the penis will often point to the pathology.

Conversely, we could probably introduce the “dix driven” sign, where the penis is found to be the cause of the pathology.