piano key sign

pi·a·no key sign

(pē'ăn-ō kē sīn)
A maneuver used to determine injury to the coracoclavicular ligament, whereby a downward pressure is applied on the distal end of the clavicle. The result is positive if the clavicle pops up after release of the downward pressure.
References in periodicals archive ?
In terms of the piano key sign, boutonniere deformity, and number of fingers with this deformity, the right hand had significantly higher figures than the left (p=0.
Our results showed that ROM limitations associated with wrist flexion and extension along with the total number of PIPJs as well as the presence of piano key sign and boutonniere deformity were more commonly observed in the right hand.
Greater deformity was observed in the right hand than left hand in our study with regard to piano key sign and boutonniere deformity, and no differences were detected concerning swan neck deformity, ulnar deviation, Z deformity, tenosynovitis, interosseous atrophy, or hypertrophic degeneration.
Piano key sign is a characteristic of caput ulna syndrome, which is caused by distal radioulnar joint instability and ulnar head subluxation.