Page 105 - Adams and Stashak's Lameness in Horses, 7th Edition

Examination for Lameness 71

horses, many lameness problems may be produced that horse from all directions. From a distance, the body type
would not occur in older, more mature horses. is characterized (stocky vs. slender); conformation is
VetBooks.ir SIGNALMENT AND USE weight shifting, and pointing are also noted. It is impor­
noted; and body condition and alterations in posture,
tant to look for changes in contour of the limbs and
Patient age and use are important considerations asymmetry between limbs.
Under normal circumstances, the forelimbs bear
when determining potential lameness conditions. For equal weight and are opposite each other. With bilateral
example, an aged crossbred horse used for ranch work, forelimb involvement, the weight may be shifted from
occasional rodeo performance, and trail riding will have one foot to the other, or both limbs may be placed too
a higher incidence of problems associated with the fore­ far out in front of the horse. In the hindlimbs, it is nor­
feet, low‐motion joints (e.g. pastern and distal tarsal mal for the horse to shift its weight from one limb to the
joints), and ligaments. In contrast, a young racehorse other. If the horse consistently rests one hindlimb and
will often have lameness problems associated with high‐ refuses to bear weight on it for a length of time or can­
motion joints (e.g. carpus and fetlock), sprain/strain of not be forced to bear weight on it at all, lameness in that
flexor support structures, and stress‐related fractures. hindlimb should be considered. Even small alterations in
Horses used for competitive trail or endurance riding limb positioning and posturing may suggest a potential
often sustain a higher incidence of sprain/strain injuries, problem and should be investigated during the lameness
tendonitis, and stress‐related fractures to the phalanges. examination.
Young cutting horses appear to be prone to stifle issues, At close observation, each limb and muscle group
and any young horse just beginning training may become should be observed and compared to its opposing mem­
lame from developmental orthopedic‐related problems. ber for symmetry. Feet are observed for abnormal wear,
hoof cracks, imbalance, size, and heel bulb contraction
(Figure 2.3). All joints and tendons and their sheaths
HISTORY (ANAMNESIS) are visually inspected for swelling, and the muscles of
A detailed medical history should be obtained on the limbs, back, and rump are observed for swelling
every horse. Records should include specific information and atrophy. Comparing one side to the other is most
regarding the duration and intensity of the lameness, important. Each abnormal finding should be ruled out
specific symptoms, the activity immediately preceding as a cause of lameness during exercise and palpation
the lameness, and any previous treatments or therapies examination. For the forelimbs, the limb with the nar­
employed. The following questions should be asked: rowest (smallest) foot and highest heel with varying
degrees of extensor muscle atrophy is usually the lame
7
1. What activity does the horse perform and did the or lamest (if the problem is bilateral) limb. The foot is
lameness occur during this activity? smaller due to chronic alteration in weight‐bearing, and
2. How long has the horse been lame? (Acute vs. the muscle atrophy results from a reluctance to extend
chronic injury.) that limb. For the hindlimb, atrophy of the middle glu­
3. Has the horse been rested or exercised during the teal and/or gracilis muscles usually indicates the lame
lameness period? (The horse may not exhibit the limb (Figures 2.4 and 2.5). Generally, if one tuber
same lameness if it has been rested.) sacrale is higher than the other and/or the pelvis appears
4. Has the lameness worsened, stayed the same, or tilted, the horse will usually have an asymmetrical gait
improved? (May indicate severity of the problem.) (Figure 2.6).
5. Was the cause of the lameness observed? (This
should include the character of the lameness at the
onset.)
6. Does the horse warm out of the lameness?
7. When do you notice the lameness most consistently?
8. What treatments have been given, and have they
helped? (Response to treatment may help predict the
prognosis of the case but may also mask the severity
of lameness and give a false impression of recovery.)
9. When was the horse last shod or trimmed?
(Lameness directly after shoeing may suggest that
the feet were trimmed too short or a nail was driven
into or near sensitive tissue.)
10. What are the abnormalities that the owner or
trainer observe or feel when they ride the horse or
watch the horse go?

VISUAL EXAMINATION AT REST
Figure 2.3. Horse with two different front feet: low heel and long
A careful visual examination is made with the horse toe on the left fore and a more upright hoof conformation on the
standing squarely on a flat surface at rest. 8,35 This should right front. Unlike many horses with this hoof conformation, this
be done at a distance and then up close, viewing the horse was lame on the left forelimb.