The function of the triceps as a whole is to flex the shoulder joint and extend the forearm.  The triceps brachii is the chief antagonist of the biceps brachii.

Etiology and Occurrence.—­Owing to the exposed position of this structure, it is not infrequently contused, the result of falls, kicks and other injuries.  The function of the triceps is such that it becomes strained upon rare occasions when a horse resists confinement of restraint in such manner that the parts are unduly tensed in contraction.  This sort of resistance may stretch the radial nerve or its branches in a way that paralysis results.  A condition known as “dropped elbow” is described by Henry Taylor, F.R.C.V.S., in the Veterinary Record[9], wherein a two-year-old colt while resisting confinement was so injured.

The triceps group because of its convenient location, constitutes the site for hypodermic injection of drugs and biologic agents, with some practitioners; and as a result, more or less inflammation may occur.  The author has observed and treated some twenty cases where an intensely painful infectious inflammation of the triceps brachii was caused by the intramuscular injection of a caustic solution by a cruel and unscrupulous empiric, whose object was to increase his practice.

Symptomatology.—­As the triceps brachii is not particularly taxed during weight bearing in the subject at rest, there may be no unnatural position assumed during inflammation of the triceps.  More or less swelling and supersensitiveness is always present, however, and great care and discrimination must be exercised in digital manipulation of the triceps region because many animals are normally sensitive to palpation of these parts.  It is sometimes difficult to correctly interpret the true state of conditions because of this peculiarity.

There is always swinging-leg-lameness, which is accentuated when the subject is urged to trot.  Where symptoms are pronounced, it is unnecessary to cause the subject to move at a faster pace than at a walk to recognize the condition.  The forward stride is shortened and in extremley painful conditions, no attempt is made to extend the leg.  It is simply carried en une piece—­flexion of the shoulder and elbow joints is carefully avoided.

Treatment.—­During the early stage of inflammation, hot or cold applications are beneficial.  Long continued use of moist heat—­fomentations—­allays pain and stimulates resolution.  Keeping in contact with the painfully swollen parts a suitable bag filled with bran, which can be moistened at intervals with warm water, constitutes a practical and easy means of treatment.  By employing this method, one is more likely to succeed in having his patient properly cared for, in that less work is entailed than if hot fomentations are prescribed.

After the acute and painful stage has subsided, a stimulating liniment is of benefit.  The subject should be kept within a comfortable and roomy box stall for a sufficient length of time to favor prompt resolution.  Wild and nervous subjects, if not so confined, will probably overexert the affected parts if allowed the freedom of a paddock or pasture.