Horse Side Vet Guide ®

Equine Health Resource

Carpal Arthritis, Carpitis

Synonyms: Popped Knee, Sore Knee, Big Knee, Swing Leg

The carpus is often incorrectly referred to by horse people as the knee. It is actually the horse’s wrist. Three joints make up the carpus. The two upper joints provide the majority of the range of motion in this high motion area. Arthritis is common in these joints, especially in older horses.

This condition generally appears to horse owners as a swollen carpus, with reduced range of motion and variable degree of lameness.

The carpus is generally quite tolerant of injury. In most equine disciplines, the carpus is not as mechanically taxed or injured compared to other areas within the limb.

Injury to the carpus is common in race horses. With fatigue of the area during racing, hyper-extension occurs causing injury and fracture of the small carpal bones, frequently resulting in chronic arthritis. Likewise, in any other discipline, horses that are trained beyond their fitness level can injure this area.


Choose horses of excellent carpal conformation. Condition horses adequately to be able to tolerate the degree of work performed.

If the carpus (or any joint) is injured, seek out a proper diagnosis. Prompt removal of fracture fragments helps to prevent the development of arthritis.

Helpful Terms & Topics in HSVGWritten, Reviewed or Shared by Experts in Equine Health

Author: Doug Thal DVM Dipl. ABVP


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