Conditions or ailments that are the cause of a problem that you see - your observation.

Your vet may diagnose

Shoe Boil, Olecranon Bursitis

Synonyms: Capped Elbow


This is an obvious ball of swelling that appears on the point of the elbow, in front of the girth. It is a fairly common condition in draft breeds and gaited horses.

It develops from repetitive trauma from lying down (when the heel of the foot or the shoe itself contacts and irritates the area). It causes the formation of a fluid filled sac (known as a false bursa) under the skin at the point of the elbow. You will notice that if you lift and fold the front limb, the heel of the shoe or hoof contacts the swollen area at the point of the elbow.

In most cases, the swelling is firm and from golf ball to tennis ball-sized although they can be larger. There is generally not associated lameness unless the bursa becomes infected. When infected, the mass can become hot, very swollen, and painful to the touch. In severe cases, the horse may appear stiff moving the limb but in most cases the condition does not cause lameness.

Ultrasound can help determine whether there is free fluid in the swelling, that can be drained.

Treatment involves protection of the area through the use of ring boots. Drainage and injection of Shoe Boils can be effective but recurrence and infection are possible.

my vet's role


Prognosis is generally good, but depends on whether or not the swelling becomes infected or is recurrent.

my role


I might observe

You might make these observations when a horse has this condition.

Very Common
Less Common
more observations

Questions To Ask Your Vet:
  • What will need to be done to prevent the recurrence of this condition?
  • Does the horse need to wear shoe boil boots?

Shoes with extended heels may increase trauma to this area and predispose to this problem. "Shoe boil boots" or "ring boots" may reduce irritation to this area and help prevent the development of shoe boil. This problem is more common when the ground is extremely hard and abrasive, so the purchase of mats and/or bedding may be helpful.

Related References:

Higgins AJ, Snyder JR eds. The Equine Manual. 2nd Ed. Edinburgh: Elsevier Saunders 2006.

Author: Doug Thal DVM Dipl. ABVP