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Chapter 14

The Wing: Infections

III SURGICAL INFECTIONS defined involucra. I see such lesions only rarely,

although they are reported.
Surgical infections are most often associated with
attempted fracture repair, including revisions. The
damaging effects to the avian bone, as seen radio- III BONE DESTRUCTION VERSUS
graphically, closely resemble those reported in BONE REDUCTION
mammals: cortical and medullary destruction, seques-

tration, inappropriate new bone deposition, plus or Localized bone loss, especially when identified in con-
minus the formation of a nonpurposeful callus (Figures junction with the surgical reduction of a fracture, is
14-1 and 14-2). These features may be accompanied by often mistakenly attributed to infection. Although this
implant dislocation. might be an accurate interpretation, it also may be
incorrect. Other possible explanations for bone reduc-
tion in a postoperative context include: (1) fragment
III OPEN FRACTURE INFECTIONS movement, (2) small-scale implant movement (cyclic

movement), or (3) full-fledged dislocation (sometimes
Open fractures are considered by many authorities to termed migration).
be already infected at the time they are initially seen,
which is a reasonable assumption given the high inci- Localized Infection
dence of failed repair in such birds (Figures 14-3 and
14-4). Open fractures in and around joints, particularly those
associated with puncture wounds, can lead to quite
localized infections, which are occasionally associated
III SYSTEMIC INFECTIONS with abscess. Unlike the more usual type of infection,
which often ranges up and down the shaft of the
Systemic infections in birds are often characterized infected bone, this localized form of osteomyelitis typi-
radiographically by multiple localized lesions, which cally is confined to the joint and immediately surround-

may assume a variety of forms. Most appear fi rst as ing areas, slowing dissolving the bony tissue, behaving
medullary clouding, and later, a surface reaction often in this respect much as a malignant synovioma. For this
becomes apparent. In unchecked infection, cortical reason, these kinds of infection are often termed low
sequestra may develop, sometimes enveloped by well- grade or smoldering (Figures 14-5 and 14-6).
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