What kind of defect does a 'capped elbow' represent?

A 'capped elbow' represents a particular defect that is classified as a skin condition rather than a defect of the leg itself. Specifically, it refers to swelling that occurs over the olecranon, which is the bony prominence of the elbow, due to friction or injury. This condition is usually caused by repeated trauma, such as a horse lying down frequently on hard surfaces, which leads to the collection of fluid in the area and results in the characteristic swelling.

While it is important to note the relationship that the condition has with the leg anatomy, particularly because the elbow is part of the forelimb, the primary nature of a capped elbow is identified as a skin issue rather than a functional unsoundness of the leg itself. The swelling may not necessarily impede the horse's movement unless it becomes severe, but it indicates a localized injury or irritation on the skin.

This distinction helps in understanding that while elbow defects may seem related to leg problems, they focus more on the soft tissue and skin reactions rather than joint integrity or leg function issues. Thus, a capped elbow is more accurately categorized as affecting the skin.