Page 1004 - Adams and Stashak's Lameness in Horses, 7th Edition

970 Chapter 9

the radius, humerus, tibia, and pelvis. A high index
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of suspicion enhances the ability to diagnose these
VetBooks.ir raphy and radiography is often needed. Tibial stress
stress fractures, and a combination of nuclear scintig­
fractures are the most common and are usually seen in
2‐year‐olds. Lameness is noted after speed work and
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abates quickly with rest. Palpation is unrewarding but
response to upper limb flexion may be dramatic. The
fracture location is unique for the Standardbred, with
the majority in the mid‐diaphysis of the tibia, whereas
fractures in Thoroughbreds are usually in the proxi­
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mal caudal or caudolateral cortex. Bilateral fractures
can be seen, even in horses with unilateral lameness
(Figures 9.20 and 9.21). Horses with scintigraphic evi­
dence of stress remodeling should be treated conserva­
tively, even if fracture is not radiographically visible.
The prognosis is good for return to racing following
appropriate rest.
Figure 9.21. A dorsolateral to palmaromedial oblique radiograph
Sacroiliac Pain of the tibia from the same horse as in Figure 9.20. Endosteal
sclerosis and callus formation along the caudolateral cortex in the
Sacroiliac pain is very common in the Standardbred
and may present as poor performance or overt lame­ mid‐diaphysis indicate the presence of a stress fracture. The horse
was rested for 6 months and made a full recovery.
ness. Drivers sometimes describe a horse’s reluctance
to take hold of the bit and think the problem is related
to the teeth. Injury occurs during slips and falls, and
damage to either the ligaments supporting the pelvis References
or the sacroiliac joint results in a similar clinical pic­ 1. Carmalt JL, Borg H, Näslund H, et al. Racing performance of
ture. Treatment includes rest and NSAIDs or injection Swedish Standardbred trotting horses with proximal palmar/plan­
of the sacroiliac joint. Both types of injury should be tar first phalangeal (Birkeland) fragments compared to fragment
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Figure 9.20. A lateral scintigraphic image of the hindlimbs in a 13. Murphey ED, Schneider RK, Adams SB. Long‐term outcome of
2‐year‐old Standardbred filly with obscure right hindlimb lameness. horses with a slab fracture of the central or third tarsal bone
Note the focal intense radiopharmaceutical uptake in the mid‐ treated conservatively: 25 cases (1976–1993). J Am Vet Med
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