Throckmorton sign (pelvis)

Dr Dan J Bell and Radswiki et al.

Throckmorton sign, also known as John Thomas sign, refers to when the penis points in the direction of unilateral disease, typically of the pelvis or hip. 

Throckmorton sign is a slang term used humorously by medical students and residents.

According to the first serious study of the sign published in 1988, the sign is less accurate than tossing a coin 3.

History and etymology

It is named after Thomas "Tom" Bentley Throckmorton (1885-1961), American neurologist and governor of the Iowa chapter of the American College of Physicians 2, not Governor of the State of Iowa, as is erroneously stated on several well-known websites!

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Article information

rID: 12270
Section: Signs
Tag: refs
Synonyms or Alternate Spellings:
  • Throckmorton's sign
  • John Thomas sign

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Cases and figures

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    Case 1: perfect example
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    Case 3: pointing to AIIS avulsion
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    Case 4: chronic osteomyelitis of left hip joint
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    Case 5: left NOF fracture
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    Case 6
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