536 
WOUNDS AND BRUISES OF THE FORE ARM. 
swelling is soft and fluctuating. Symptoms of inflammation (warmth 
and pain) are in rare cases present ; but, as a rule, there is only a 
fluctuating swelling of an oval or round form, varying from the size of 
a hazel-nut to that of a hen’s egg. 
The swelling is produced by distension of the bursa olecrani with 
serum, which sometimes contains fibrin (bursitis sero-fibrinosa); blood 
is rarely met with. It never interferes with movement, but is a blemish 
which is difficult to remove, the cause being always at work. Animals 
accustomed to lie in the position described cannot he broken of the 
habit, especially as the swelling is painless. Simple puncture and 
removal of contents are therefore not sufficient, and, owing to the flatness 
of the swelling, a ligature cannot be applied. If necessary, the enlarged 
bursa must be surgically removed, though operation is difficult, and, as 
a rule, cicatricial thickening remains. Before operating, it is best to 
give a dose of morphine. The hair is removed and an incision made 
over the swelling in the long axis of the limb. The bursa is then 
separated from neighbouring parts, care being taken not to incise it, 
which would greatly increase the difficulty of the operation. The 
greatest precaution is required in separating the bursa from the elbow, 
with which it is firmly united, and the bone must not be exposed, as 
this would delay healing, and prevent the formation of a cicatrix. 
When excision has been successful, it is sometimes possible, by observing 
antisepsis, to produce healing by first intention. The operation wound 
is carefully dressed, and thick layers of wadding or wood-wool applied 
to the posterior surface of the elbow to prevent further bruising when 
the animal lies down. When healing by first intention is impossible, 
the wound must be treated on general principles. A soft bed is particu¬ 
larly requisite. Remnants of the bursa, which remain after enucleation, 
may be destroyed by irritants like nitrate of silver, and a proper 
granulating surface so produced. 
YL—WOUNDS AND BRUISES OF THE FORE ARM. 
Anatomy. In the horse, the fore arm (antibrachium) has, as a basis, the 
radius and ulna, which are surrounded by numerous muscles, tendons, and 
fasciae. The following surface-markings should be noted :—Towards the outside 
lower end of the fore arm a long depression, slightly inclined backwards, and 
marked at its centre by a prominent cord, the tendon of the extensor suffra- 
ginis. In front of this runs another cord about one inch in breadth, the 
tendon of the extensor pedis. Towards the front of the limb, and at the 
boundary of the external and anterior faces, another depression, and still 
further forward and inward, the tendon of the extensor metacarpi magnus, 
about 1^- inches in breadth. 
Behind the first-named depression lies the flexor metacarpi externus, 
which is. bounded behind by the flexor metacarpi medius and the flexor 
metacarpi internus. 
