Watson's test is a diagnostic

Medical diagnosis

Medical diagnosis refers both to the process of attempting to determine or identify a possible disease or disorder , and to the opinion reached by this process...

 test for instability between the scaphoid and lunate bone

Lunate bone

The lunate bone is a carpal bone in the human hand that may be distinguished by its deep concavity and crescentic outline. It is situated in the center of the proximal row of the carpus region between the fore arm and hand...

s of the wrist

Wrist

In human anatomy, the wrist is variously defined as 1) the carpus or carpal bones, the complex of eight bones forming the proximal skeletal segment of the hand;...

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Test procedure

To perform the test, the examiner grasps the wrist with their thumb over the patient's scaphoid tuberosity which is on the palmar side of the wrist (i.e. the same side as the palm). For the test, the wrist needs to be in slight dorsiflexion.The patient's wrist is then moved from ulnar

Ulnar deviation

Ulnar deviation, also known as ulnar drift, is a hand deformity in which the swelling of the metacarpophalangeal joints causes the fingers to become displaced, tending towards the little finger. Its name comes from the displacement toward the ulna...

 to radial deviation. The examiner will feel a significant 'clunk' and the patient will experience pain if the test is positive. For completeness, the test must be performed to both wrists for comparison. If the scapholunate ligament

Scapholunate ligament

The scapholunate ligament is a ligament of the wrist.The scapholunate ligament is an intraarticular ligament binding the scaphoid and lunate bones of the wrist together. It is divided into three areas, dorsal, proximal and palmar, with the dorsal segment being the strongest part. It is the main...

 is disrupted, the scaphoid will tend to flex to the palm of the hand and the lunate will face to the dorsal (back) side of the hand. This procedure reproduces the subluxation

Subluxation

A subluxation may have different meanings, depending on the medical specialty involved. It implies the presence of an incomplete or partial dislocation of a joint or organ. The World Health Organization defines both the medical subluxation and the chiropractic subluxation...

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External links

• Watson's test: A WikiDoc article on the same subject.
• 'Watson test': An entry from Wheeless's Textbook of Orthopaedics.

This article uses text from the Watson's test article on WikiDoc.