Growing Pains–Physitis

Learn about this disease in young horses that leads to enlarged, painful areas just above the knees or hocks.

No account yet? Register


Some of you might recognize this syndrome as the disease formerly known as epiphysitis. This disease–or more correctly disturbance of growth–is most commonly recognized as that problem when foals get the enlarged, often painful areas just above their knees (carpi) or hocks. But as my clients have been asking me: What is it, and what does it mean for my foal?

Physitis is simply defined as inflammation of the growth plate (physis = growth plate, itis = inflammation). Growth plates are the areas within the bones of young horses from which the bones grow or lengthen. (In adults, the plates have "closed" and are no longer present.) Technically, the growth plate is referred to as the metaphyseal growth plate. Each region of a bone has a different name, with the middle of the bone called the diaphysis, the slightly flared portions of the bone before the growth plate called the metaphysis, and the ends of the bones, where the articular cartilage is located, is called the epiphysis (see "Long Bone Anatomy" on page 63).

In young horses (where growth plates are present), the growth plate occurs within the metaphysis and becomes the line that separates the metaphysis and the epiphysis

Create a free account with to view this content. is home to thousands of free articles about horse health care. In order to access some of our exclusive free content, you must be signed into

Start your free account today!

Already have an account?
and continue reading.


Written by:

Christina S. Cable, DVM, Dipl. ACVS, owns Early Winter Equine in Lansing, New York. The practice focuses on primary care of mares and foals and performance horse problems.

Related Articles

Stay on top of the most recent Horse Health news with

FREE weekly newsletters from

Sponsored Content

Weekly Poll

sponsored by:

Where do you go to find information on pituitary pars intermedia dysfunction (PPID)? Select all that apply.
91 votes · 158 answers

Readers’ Most Popular

Sign In

Don’t have an account? Register for a FREE account here.

Need to update your account?

You need to be logged in to fill out this form

Create a free account with!