Throckmorton sign

Throckmorton sign
 n.— «One of these medical “tidbits” is the infamous “Throckmorton sign” for hip X-rays. This sign, the student is told, means that the penis is always pointed towards the side with the problem. This is always discussed while looking over a series of X-rays and inevitably proves true. The students are impressed and a bit baffled. Eventually, they learn that X-ray techs always take the X-ray picture with the patient on his side with the problem hip down closest to the film. The area closest to the film is seen more clearly on X-ray, so you want that to be the problem side. Gravity does the rest.» —“medical malarkey” by Steve Carder Humor List  Dec. 21, 2000. (source: Double-Tongued Dictionary)