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Chapter 15

The Wing: Posttraumatic

Osteoarthritis

III INCONGRUITY AND rendering it incongruent or alternatively by damaging
DESTABILIZATION: FORMULAS a periarticular or intraarticular ligament, causing
FOR OSTEOARTHRITIS excessive motion. A severe capsular injury can have a
similar destabilizing effect.
Posttraumatic osteoarthritis is caused by joint incon- Sprains that are aggravated before fully healing
gruity, which most often occurs as the direct result of may eventually lead to elongation of one or more of
an articular fracture, fracture-dislocation, or simple the damaged ligaments, which can produce instability
dislocation. Severe sprains (third degree) may also and later osteoarthritis. This destabilization is always a
eventually lead to osteoarthritis by allowing one or concern when migratory wild birds must be released
more articular elements to exceed their normal range prematurely.
of motion. Infectious arthritis may lead to osteoarthri- Figures 15-1 through 15-3 illustrate some of the
tis either by destroying a portion of the joint and thus effects of posttraumatic osteoarthritis.
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