Page 635 - Adams and Stashak's Lameness in Horses, 7th Edition

Lameness of the Proximal Limb 601

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A B
Figure 5.4. Radiographs demonstrating how lines can be used to determine the site of angulation in carpal ALD cases. (A) Distal radial
epiphysis. (B) Intra‐articular.

this is as simple as stall rest and proper trimming for The techniques for applying tube casts and splints
normal break‐over of the hoof. In foals with carpal val- include a bandage alone, bandage plus PVC pipe placed
gus, the dorsomedial aspect of the foot is typically worn on the caudal aspect of the limb, and bandage plus a cast
because the foal will break over in that location. that is either placed on the caudal aspect of the limb or
Therefore, the dorsolateral aspect should be trimmed to a true tube cast that surrounds the limb. Care must be
achieve a normal‐appearing foot. Some advocate medial taken when applying splints and casts as foals are
hoof extensions, although there is concern that this susceptible to pressure sores. Instead of PVC pipe splits,
could lead to ALD in the fetlock joint, and some advo- the author prefers cast material elongated over the
cate the use of excessive dorsolateral trimming. The back of the limb with similar placement to PVC pipe.
author prefers to use extensions instead of excessive Regardless of the type of application, these should be
trimming, especially in foals that are toed out in addi- changed every 7–10 days and usually are needed for
tion to being carpal valgus. In the author’s experience, approximately 14 days. The author tries to minimize
prolonged use of medial or lateral extensions can lead to external coaptation, which weakens the limb and can
abnormal changes in the growth of the fetlock joint, at cause significant sores.
least until the time of distal third metacarpal physeal Keep in mind that significant problems can result in a
closure (3–4 months). foal in a tube cast or in a splint, particularly slippage of
Nutritional status of the foals should also be assessed the cast or the foal outgrowing the cast. Cast sores are a
and corrected if abnormalities are detected. major problem in foals; if there is any concern about the
If the degree of palpable joint laxity is significant, the foal’s use of the limb or if heat is detected in the cast, it
angulation is severe, and/or there is decreased ossifica- is best to change it at that time. It is recommended
106
tion of the cuboidal bones, then a tube cast or splints that tube casts and splints be applied under general
may be necessary to axially align the joints (Figure 5.5). anesthesia after physically straightening the limb. The
A tube cast or splint is usually applied from the proxi- author has successfully used a customized sling and
mal radius distally to the level of the fetlock joint. It is buggy system, especially in foals that have incomplete
important to leave the foot out so stimulation of muscle ossification of their carpal and tarsal bones.
contraction of the forelimb can be continued to mini- In some cases of mild ALD, brief turnout may be help-
mize limb weakening. ful when the foal is thought to be strong enough.