Which finding is a piano-key deformity in the shoulder girdle injury context?

Which finding is a piano-key deformity in the shoulder girdle injury context?

• A. Subluxation of acromion
• B. Posterior dislocation of humeral head
• C. Piano-key deformity with distal clavicle elevation
• D. Clavicle fracture with shoulder droop

Answer: (C)

Piano-key deformity reflects an acromioclavicular joint injury with disruption of the ligaments that hold the distal clavicle in place. When the examiner presses on the distal clavicle, it can be depressed, and after release it springs back, resembling a piano key. This happens because the coracoclavicular ligaments are torn, allowing the distal clavicle to be elevated relative to the acromion and become unusually mobile. The finding that explicitly describes this scenario is distal clavicle elevation with a piano-key feel, which is the hallmark sign of AC joint separation. Other shoulder girdle injuries, like a humeral head dislocation or a clavicle fracture with droop, produce different signs and do not present with the classic piano-key maneuver.

Piano-key deformity reflects an acromioclavicular joint injury with disruption of the ligaments that hold the distal clavicle in place. When the examiner presses on the distal clavicle, it can be depressed, and after release it springs back, resembling a piano key. This happens because the coracoclavicular ligaments are torn, allowing the distal clavicle to be elevated relative to the acromion and become unusually mobile.

The finding that explicitly describes this scenario is distal clavicle elevation with a piano-key feel, which is the hallmark sign of AC joint separation. Other shoulder girdle injuries, like a humeral head dislocation or a clavicle fracture with droop, produce different signs and do not present with the classic piano-key maneuver.