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


Hard Bump on Inside of Lower Hock


The hock is an anatomically complicated area. Defined, discrete swellings in particular areas provide clues to various conditions of the hock.

In most cases, a hard bump located low on the inside of a horse's hock is a sign of advanced arthritis of the lower hock joints (a/k/a Bone Spavin). However, swellings in this area can result from other causes, including direct blunt trauma, infection, tumor, or may be associated with other structures in this area.

  • Code Orange

    Call Your Vet at Their First Available Office Hours
    • If lameness is noticeable at the walk.
  • Code Yellow

    Contact Your Vet at Your Convenience for an Appointment
    • Even if the horse does not appear to be lame to you.
    • If you are considering purchase, be sure to have a purchase exam performed.
    • Your vet can rule out common lameness conditions and recommend treatment or management.
You also might be observing
Very Common
Less Common
more observations

your role


What To Do

Evaluate this area for swelling, especially in performance horses, and most commonly in western performance horses. If you notice a bump here, assess the area for heat and a pain response to pressure. Is the swelling bone hard or can it be deformed by gentle pressure? Assess the horse for lameness at the walk and trot. Always compare any swelling to the same area on the opposite limb and to the same area on your other horses.

Share your findings and concerns with your veterinarian.

your vet's role

A veterinary exam is required to understand the significance of a swelling here. They will assess the area and likely perform a lameness exam. Your vet knows the anatomy of the hock region and can determine whether this bump is truly indicative of hock arthritis, or not.

Not all horses with swellings here are lame. Some horses with a bump in this location will already have fused lower hock joints and no lameness. If the horse is lame, it is not necessarily the result of a swelling here.

In order to define bone involvement and the degree of hock arthritis, radiography is necessary.
Questions Your Vet Might Ask:
  • Is the area painful to pressure?
  • Are you considering the horse for purchase, or currently own the horse?
  • Is the horse limping or lame?
  • When did you first notice this problem?
  • Is it hard or soft?
  • How does this limb compare to the opposite hind limb?
  • If the horse is lame, how lame?
  • What are the results of the Whole Horse Exam (WHE)?

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
more diagnoses

further reading & resources

Author: Doug Thal DVM Dipl. ABVP