This is the fourth in a series on straightness and its effects on the hoof.

Read "How Straightness Affects the Equine Hoof", "How Leaning Affects Equine Anatomy" and "How Crooked Carriage Affects Equine Performance"

Those who have studied the first three installments in this series are already well up on what crooked carriage in horses is, the anatomy that underlies and permits it and what it looks like in the ridden horse.

This installment brings the focus down to the hoof in two parts: first, a biomechanical model of hoof form; and second, how the model’s predictions concerning horses that habitually carry themselves crookedly work out in real-world examples.

Hoof-Cone Model

A normal horse hoof is shaped in three dimensions like a section of a cone. This fact is the basis for understanding what normal hoof geometry looks like. All biomechanical models are simplifications of reality that can be refined step-by-step until the model closely resembles the real thing.

Figure 1a models the hoof capsule as a regular cone with an axis at 90 degrees to…