Page 160 - The Veterinary Care of the Horse

capsule is distended, which may cause pain, but it also places the extensor tendons under

tension, so the results need to be interpreted with care, even by an experienced veterinary
VetBooks.ir surgeon.

Finally, one also has to be careful to check that a positive response is relevant to the
lameness being investigated as many horses have multiple sites of pain. The results often

have to be considered together with the results of nerve blocks.

PALPATING THE HORSE

The next step of the examination is for the vet to examine the area of suspicion closely and to

feel the horse for any indication of pain, heat, swelling or muscle tension. Very often the
whole of the horse is palpated to make sure that nothing is overlooked. This is important as
the injury causing the lameness may have developed as a result of the horse compensating for

a less obvious problem elsewhere. Racehorses, for example, often have problems in the
diagonally opposite pair of limbs. Forelimb injuries such as tendon strains may show up

more in one leg but tend to occur bilaterally.
The horse is systematically and methodically palpated all over. Each limb is palpated

while bearing weight and also while raised from the ground so the tendons and ligaments can
be individually felt. The knee, fetlock and pastern joints are gently flexed and rotated to see if

this causes pain. The vet will also feel for any grating of bone against bone – known as
crepitus. This can be heard or felt in cases of osteoarthritis or if a fracture is present. The

neck and back are carefully checked. Back pain can be the primary complaint but it is often
secondary to pain elsewhere in the body.

RANGE OF MOVEMENT
While the limb is raised from the ground, the vet will compare the range of movement of the

various joints with that of the opposite limb and from experience with what is expected of a
horse of that type and age. Reduced movement may occur in a horse with advanced

osteoarthritis of a joint and resultant fibrous thickening of the joint capsule. An acute joint
sprain is likely to be extremely sensitive to even gentle passive movement. These tests must

be carried out with sensitivity and care as horses vary considerably in their tolerance to pain.
The minimum of force should be used.

EXAMINATION ON A CIRCLE

Some types of lameness are only visible or are more obvious on a circle, for example when
the horse experiences pain in both front feet. Ideally the horse should be lunged on a hard and

a soft surface if the facilities are available (Figure 4.9). This is because some types of