radiology Radiology ( ) is the medical specialty that uses medical imaging to diagnose diseases and guide treatment within the bodies of humans and other animals. It began with radiography (which is why its name has a root referring to radiation), but tod ...

, the Terry-Thomas sign is a

scapholunate ligament The scapholunate ligament is a ligament of the wrist. Rupture of the scapholunate ligament causes scapholunate instability, which, if untreated, will eventually cause a predictable pattern of wrist osteoarthritis called scapholunate advanced co ...

dissociation on an

anteroposterior Standard anatomical terms of location are used to describe unambiguously the anatomy of humans and other animals. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position provi ...

view of the wrist. Most commonly a result of a fall on the outstretched hand ( FOOSH), the

ruptures resulting in separation of the

lunate Lunate is a crescent or moon-shaped microlith. In the specialized terminology of lithic reduction, a lunate flake is a small, crescent-shaped lithic flake, flake removed from a stone tool during the process of pressure flaking. In the Natufian cu ...

and

scaphoid bone The scaphoid bone is one of the carpal bones of the wrist. It is situated between the hand and forearm on the thumb side of the wrist (also called the lateral or radial side). It forms the radial border of the carpal tunnel. The scaphoid b ...

s. This burst causes the

to dorsally rotate. A gap of more than 3mm is

pathognomonic Pathognomonic (synonym ''pathognomic'') is a term, often used in medicine, that means "characteristic for a particular disease". A pathognomonic sign is a particular sign whose presence means that a particular disease is present beyond any doubt. ...

for scapholunate dissociation. The resulting separation between the scaphoid and lunate bones leaves a space on the x-ray that is similar to the gap comedian

Terry-Thomas Terry-Thomas (born Thomas Terry Hoar Stevens; 10 July 1911 – 8 January 1990) was an English character actor and comedian who became internationally known through his films during the 1950s and 1960s. He often portrayed disreputable members ...

had between his front teeth. For newer radiology students who do not know who Terry-Thomas was, this finding might also be known as the

David Letterman David Michael Letterman (born April 12, 1947) is an American television host, comedian, writer, producer, and auto racing team owner. He hosted late-night television talk shows for 33 years, beginning with the February 1, 1982, debut of ''Late N ...

sign.

References

External links

Entry on RadiopaediaCase study and history from PubMed
Radiologic signs {{Med-sign-stub