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Chapter 9

The Wing: Fracture Types

and Tendencies

III ON BROKEN WINGS tures in birds are frequently accompanied by disloca-
tions (Figure 9-1).
First, a pair of important principles should be stated: Nowhere is an anatomical reduction more impor-
(1) the wing is more susceptible to injury than any tant than in the case of articular fractures. Even so,
other part of a wild bird and (2) wing injuries, either there is a high incidence of posttraumatic osteoarth-
directly or indirectly, often prove fatal. ritis that usually leads to some degree of disability.
The projectile nature of the wings makes them Extra articular and periarticular bone deposits, termed

extremely vulnerable to in-flight injury, especially by impingement exostoses, may interfere with joint
man-made obstacles such as power lines, fences, wire, movement to the extent that normal fl ight proves
and the like. Although we occasionally encounter wild impossible.
birds with one or more healed fractures, this is clearly
the exception and most wild birds that break their Simple Fractures
wings do not survive long enough to heal, unless
they are provided with nourishment and a protected Simple, or two-piece, fractures occur most often in the
environment in which to recover (treatment not shafts of long bones. Some breaks are barely percepti-
withstanding). ble, appearing as one or more fi ne cracks in the bone,
and others are immediately evident, based on obvious
discontinuity, misalignment, and override (Figure 9-2).
III FRACTURE TYPES Simple fractures are usually described according
to orientation of the break relative to the long axis
of the bone: transverse, short or long oblique, and
Articular Fractures
longitudinal.
Articular fractures are among the most devastating Simple transverse fractures reduced with a single
of all wing injuries. Not only do they nearly always intrameduallary pin are prone to rotation and sheer-
prevent future flight, but they also make it diffi cult or ing unless counteracting stabilization techniques are

impossible for birds to feed adequately, causing them used.
to weaken and eventually starve or fall prey to an
opportunistic predator. Comminuted Fractures
From a diagnostic perspective, shoulder fractures
are the most difficult to diagnose because of the exten- The comminuted fracture is usually heralded by its

sive superimposition of the four bones that comprise many pieces, which are typically clustered in the
the humeral joint, or pectoral girdle, as it is also known. diaphyseal region of long bones such as the humerus
These bones include the humerus, coracoid, scapula, (Figure 9-3), radius, and ulna. Three-piece comminuted
and clavicle. Although the fourth bone, the clavicle, is fractures often feature a central, broad-based triangu-
not strictly a part of the shoulder joint, it plays an lar fragment that resembles the silhouette of a butter-
integral role in fl ight mechanics. fl y, thus the term butterfl y fragment.
Articular fractures of the cubital joint, or elbow, are Generally, comminuted fractures take longer to heal
diagnostically far less complex but can sometimes be than simple fractures, are more inclined to delayed

difficult to identify when displacement is minimal and union because of related vascular disruption, and
only one view is available. Unfortunately, elbow frac- usually lead to some degree of malunion.
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