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Chapter 10

The Wing: Fracture Healing

and Nonhealing

III FRACTURE HEALING
Skill of the Surgeon. Operator skill, or in this instance,
the ability of the surgeon to reduce and stabilize a
What Does Healing Mean?
fracture, is the sum of the surgeon’s initial clinical
Healing refers to the return of most or all function, for training plus his or her subsequent experience (Figure
example, a broken wing is healed sufficiently to enable 10-3). It becomes possible by this measure to predict

a bird to fly (Figure 10-1) or a fractured leg is healed the likelihood that a particular fracture is or is not
well enough to enable a bird to walk, or launch, or likely to heal or achieve a positive outcome.
land. This healing is referred to as functional healing.
Another way to understand healing is in a restorative Complications. Orthopedic and other types of surger-
sense, for example, a previously broken bone has been ies that do not go as planned are often attributed to
restored to its preinjury appearance. Unfortunately, complications, which is a rather imprecise pseudo-
full restoration may require months or even years to medical term that can refer to a wide variety of unan-
come about (Figure 10-2), and thus the term becomes ticipated difficulties encountered during or after

clinically impractical. surgery. Such problems can range from trivial to dis-
abling to life-threatening. For example, a small amount
of bone cement may spill onto the surrounding muscle
What Determines Healing Time?
during the installation of a prosthetic hip, and this
It is impossible to predict a precise healing time for any should not discernibly affect healing. On the other
given fracture—in a bird or any other creature for that hand, a major artery may be inadvertently severed,
matter—but it is reasonable to estimate a range of leading to substantial blood loss, or a major nerve may
dates, or an approximation of dates, usually expressed be accidentally transected, causing paralysis.
in weeks, by which time most such fractures will have
healed. For example, most simple nondisplaced, mid-
shaft radial fractures will heal in 3 to 4 weeks provided Radiographic Features
that the associated ulna is intact. If the ulna is also
fractured but not severely displaced, the injury will Purposeful Versus Nonpurposeful Callus Formation.
likely require an additional week or two to heal. As pointed out previously, healing is such a highly
variable process that depends on a number of different
Severity of the Injury. The severity of an injury, in the considerations. Thus there are no specifi c healing
case of a bone the number of fragments and their times, only prognostic estimates that are confi rmed or
degree of displacement, is the principal determinant of modified according to subsequent progress examina-

healing time. To heal, the blood supply of a bone must tions. The single strongest radiographic indication of frac-
be restored to the extent it was disrupted by the facture. ture healing is the development of a purposeful callus.
Thus the greater the number of fracture fragments and A purposeful bony callus is one that forms in and

the greater their separation, then the greater the around the fracture, serving first to unite and then to
damage to the associated circulation. Proper healing solidify the fragments. Early in its development a
requires a proper blood supply. callus may be invisible because of an absence of mineral
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