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Chapter 12

The Wing: Dislocation, Fracture-

Dislocation, and Traumatic

Amputation and Avulsion

III DISLOCATION an articular fracture of the distal humerus (Figure
12-3). Most shoulder dislocations are associated with a
Pure dislocations of the humeral, cubital, radiocarpal, displaced coracoid fracture, with scapular or clavicular
or ulna carpal joints of birds are not nearly as frequent injury (Figure 12-4).
as combined fracture-dislocations. The elbow is dislo-
cated most often (Figure 12-1), followed by the
shoulder. III TRAUMATIC AMPUTATION
AND AVULSION

III FRACTURE-DISLOCATION Traumatic amputations occur most often in the distal
portion of the wing at the level of the midmetacarpus
Fracture-dislocations occur most commonly in the or distal metacarpus, typically removing the distal
elbow joints of birds. As with all dislocations, the asso- half of the wing in the process (Figures 12-5 through
ciated ligaments are stretched, torn, or avulsed and 12-7). Less often, the second digit is simply ripped

termed first-, second-, and third-degree sprains. Typically, free of its attachment to the metacarpus, taking
both the humeroulnar and humeroradial joints are dis- the distal part of the wing along with it (Figure 12-8).
located and/or fractured (Figure 12-2). Less frequently, Such injuries effectively pinion the bird, making fl ight
one or both cubital joints are dislocated secondary to impossible.
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