Page 1080 - Adams and Stashak's Lameness in Horses, 7th Edition

1046 Chapter 10

TREATMENT protein supplements, and the quantity of alfalfa hay
should be reduced or replaced with good‐quality grass
Treatment of physitis in young foals needs to incor­
VetBooks.ir porate treatment of the symptoms (e.g. pain) but also should be decreased if possible. Specific balanced rations
hay. With nursing foals, the milk production of the mare
4
needs to treat the source. For most, nonsteroidal anti‐
for growing horses to minimize the development of physi­
inflammatory drugs (NSAIDs) are indicated to decrease
physeal inflammation and improve the animal’s stiff tis and other DOD diseases have been developed and can
be considered.
gait. NSAIDs help diminish pain and may prevent the In cases of septic physitis, early recognition and
development of flexural deformities. NSAIDS are often aggressive management with systemic and local (intra­
required for at least 2–3 weeks to completely resolve venous or intraosseous) antimicrobials are required. In
6
the inflammation. Monitoring for gastrointestinal and/ select cases, debridement of osteolytic, necrotic periphy­
or renal complications is advisable. Phenylbutazone is a seal bone is required. Premature closure of the growth
common formulation used for musculoskeletal disor­ plate with subsequent ALD or limb shortening may be
ders. Alternatively, COX‐2 selective formulations complicating sequela. 6,24
14
(such as firocoxib or meloxicam) may be preferable due
to less risk of adverse systemic effects. 14
If the source of the physitis is obvious, then it needs PROGNOSIS
to be treated appropriately. For example, if an ALD is
present, the greatest degree of physeal abnormalities Fortunately, the majority of physitis cases are mild
usually corresponds to the direction in which the limb is and are often self‐limiting. Most cases resolve when
deviated. For example, weanlings with significant skeletal maturity is reached and growth of the affected
physitis of the medial aspect of the distal radial physis physis ceases. In many cases, a mild amount of physitis
often develop carpal varus (Figure 10.11). This suggests may be part of the normal aspects of bone modeling and
that the physitis has contributed to arrested growth on remodeling; as such, foals simply grow out of the prob­
the medial aspect of the physis. Autocorrection of these lem. 5,6,23 More severe cases of physitis, such as those that
deviations is unlikely, and growth retardation surgery develop concurrent angular or flexural limb deformities
on the opposite side of the physis is often necessary to or those resultant from sepsis, may cause residual prob­
correct the ALD. lems severe enough to limit future athletic soundness of
Most of the time, the exact source of the physitis not the horse. 5,6
easily identified, but the amount of exercise can be
adjusted since both the intensity and duration of exercise
influence physeal stress. If the foal is getting too much References
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prevent further trauma to the physis. This can be growth plate chondrogenesis. Endocrinology 2002;143:1851–1857.
5
accomplished via confinement or by changing the 2. Banks WC, Kemler AG, Guttridge H, et al. Radiography of the
exercise routine such that smaller segments of exercise tuber calcis and its use in Thoroughbred training. Proc Am Assoc
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6
weanlings. If a foal spends the first few weeks of its life 4. Baxter GM, Turner AS. Diseases of bone and related structures. In
recumbent, the bone needs to adapt to the loads placed Adams’ Lameness in Horses, 5th ed. Stashak TS, ed. Lippincott
Williams and Wilkins, Philadelphia, 2002;401–457.
on it when the foal is standing. If the exercise level 5. Bramlage LR. Physitis in foals. Proc Am Assoc Equine Pract
increases dramatically in this time frame, adaptation of 1993;39:57–62.
the bone will not occur quickly enough, resulting in 6. Bramlage LR. Physitis in the horse. Equine Vet Educ
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5
control of exercise is important in these particular foals. 7. Breur GJ, VanEnkevort BA, Farnum CE, et al. Linear relationship
between the volume of hypertrophic chondrocytes and the rate of
In the case of an unstable physis secondary to trauma, longitudinal bone growth in growth plates. J Orthop Res
some protection with external coaptation may be 1991;9:348–359.
required. However, completely protecting the physis 8. Brighton CT. Morphology and biochemistry of the growth plate.
from weight‐bearing forces, as could be achieved with a Rheum Dis Clin North Am 1987;13:75–100.
cast, is contraindicated unless absolutely required, as 9. Brighton CT, Sugioka Y, Hunt RM. Cytoplasmic structures of epi­
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if it involves multiple locations. Often a geographic nutri­ 10. Butler JA, Colles CM, Dyson SJ, et al. The tarsus. In Clinical
Radiology of the Horse, 4th ed. Wiley Blackwell, Ames, IA,
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tein while supplying National Research Council (NRC) 13. Denoix JM, Jeffcott LB, McIlwraith CW, et al. A review of terminol­
minimum requirements of other essential nutrients. In ogy for equine juvenile osteochondral conditions (JOCC) based on
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