What you see. The starting point for addressing any equine health related issue is your observation.


Swelling of Joint or Tendon Sheath in Lower Leg


Joints are located at the meeting of two bones. Each bone end is covered with a smooth layer of cartilage that makes up the joint surface. A joint capsule surrounds the joined ends. The inner lining of this capsule produces fluid that bathes and lubricates the cartilage. Tendon sheaths also contain fluid that lubricates tendons as they passes over or around joints.

Inflammation and injury cause the production of more fluid within these enclosed capsules, resulting in fluid swelling that is well defined. A well defined fluid-filled swelling near a joint is likely to be within a joint or tendon sheath. Whether there is cause for concern depends on many factors. The underlying cause could be minor (aka "windpuffs"). It could also be a sign of a more severe problem with the enclosed tendon.

  • Code Red

    Call Your Vet Immediately, Even Outside Business Hours
    • If lameness is noticeable at the walk.
    • If the results of the Whole Horse Exam (WHE) in the resting horse indicate fever (Temp >101F/38.3C) or heart rate greater than 48 BPM.
  • Code Yellow

    Contact Your Vet at Your Convenience for an Appointment
    • If you consider this a chronic and relatively mild problem that is not changing rapidly.
    • Even if the horse does not appear to be lame to you.
    • If the results of the Whole Horse Exam (WHE) suggest the horse is otherwise normal.
You also might be observing
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your role


What To Do

Feel the area for range of motion, heat and pain to pressure. Assess the horse for lameness at the walk and trot. Communicate your findings and concerns to your vet.

If your horse is lame, place them in a stall or small turnout until your vet can examine them.

NEVER purchase a horse with a swelling here without a veterinary pre-purchase exam!

What Not To Do

Do not force a horse with a mysterious swelling on a limb to exercise. This could worsen the injury.
NEVER purchase a horse with a swelling here without a veterinary pre-purchase exam!

your vet's role

Our job is to determine whether or not the problem results from normal wear and tear or indicates a significant problem. The single most important consideration is whether or not the horse is lame, and if so, whether the lameness points at this location as the cause. That requires a lameness exam. Once that is done, then ultrasound, x-ray and other diagnostics may be used to provide more detailed information.
Questions Your Vet Might Ask:
  • When did you first notice the swelling?
  • What is the horse's age, sex, breed and history?
  • Do you notice any lameness?
  • How severe do you think the lameness is?
  • Does the horse show a pain response when you apply pressure to the area?
  • Does static flexion of the limb hurt?
  • Do you notice heat in the area?
  • Does the horse react in pain when the limb is raised or manipulated?
  • Does your horse have a history of an old injury or chronic lameness of that limb?

Diagnoses Your Vet May Consider

The cause of the problem. These are conditions or ailments that are the cause of the observations you make.

Very Common
Less Common
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Treatments Your Vet May Recommend

A way to resolve the condition or diagnosis. Resolving the underlying cause or treating the signs of disease (symptomatic treatment)

Very Common
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Author: Doug Thal DVM Dipl. ABVP