The withers are made up of the spines of the thoracic vertebrae, ligament and connective tissue. Simple skin wounds of this area may heal well, but the area is well known for complicated and slow wound healing.

Wounds involving the withers can be traumatic (from running under a tree for instance or from bites from other horses). They are often accompanied by pain, swelling and chronic drainage. This complex of problems can also be part of a condition known as fistulous withers, an infection casused by Brucella bacteria. This condition is rare, but still occasionally seen today.

This is an area commonly traumatized by ill-fitting or poorly positioned saddles. When the withers is traumatized by saddle pressure, it often swells severely, become extremely painful to the touch for a time and then ruptures, draining reddish or pus-like drainage for a variable period of time. In more severe cases, the underlying bony spines of the vertebrae can even become infected. In these cases, there may or may not be obvious saddle sores visible. These injuries can be very painful and can take a long time to heal.