Page 206 - Canine Lameness

178 13 Carpal Region

(A) (B) Figure 13.5 Salter-Harris (SH) fracture classification: the
SH classification is intended for fractures in juveniles that
are involving variable components of the (a) metaphysis,
(b) epiphysis, and (c) physis. (A) SH Type I fractures describe
a fracture directly though the physis without a fracture
component of the metaphysis or epiphysis. (B) A Type II
fracture, which is the most common physeal fracture type
in dogs, involves the physis and a portion of the
metaphysis. (C) Type III fractures involve a portion of the
physis and epiphysis and, therefore, are articular fractures.
(D) Type IV fractures involve all three components and,
therefore, are also a type of articular fracture. (E) Type V
CARPAL REGION (C) (D) compressive fractures of the physis, both of which cannot
fractures are symmetric, and (F) Type VI are asymmetric
initially be identified radiographically since no
displacement is present.

(E) (F)

13.3.2 Physical Examination

Carpal fractures can lead to varying degrees of lameness from a mild, weight-bearing lameness to
a severe, toe-touching or non-weight-bearing lameness based on the potential loss of carpal sta-
bility. Slab fractures, chip fractures, and non-displaced carpal bone fractures often lead to mild
lameness that may be more severe after a period of rest (dogs “warm out of the lameness”) or after
a period of heavy exercise. Fractures with ligamentous disruptions and loss of carpal stability are
incompatible with weight-bearing and lead to a toe-touching stance and severe lameness. On
palpation, carpal fractures are associated with mild and focal swelling to severe and diffuse swell-
ing, based on carpal disruption. Swelling is generally most severe on the dorsal aspect of the joint.
Carpal flexion is decreased and range of motion generally elicits a pain response. To flex and
extend the carpus, the leg is held with one hand proximal to the carpus, and the other hand is
placed distal to it. Motion of the elbow and shoulder joints should be avoided when performing
the evaluation of the carpus to reduce a possible response from a painful source in these areas. A
normal carpus can be flexed to a point where the metacarpal pad contacts the caudal surface of
the antebrachium.