The coffin joint is the most distal joint in the equine limb and, consequently, comes under a tremendous amount of pressure from above. Jim Ferrie, an International Horseshoeing Hall Of Fame member from Newmilns, Scotland, told attendees at the 2010 International Hoof-Care Summit that he and the eight members of his multi-farrier practice often address lameness cases involving the joint. Because nearly two-thirds of a horse’s weight is carried on its front feet, Ferrie finds the coffin joint provides more problems on that end of the horse than the other.
Ferrie utilizes effective trimming and shoeing strategies to address the coffin joint imbalance. However, to treat these situations, Ferrie stresses the necessity of understanding the surrounding structures.
The coffin joint is the intersection of three bones: the coffin bone, short pastern bone and the navicular bone. It functions as both a hinge joint and a saddle joint, allowing for flexion, extension and a moderate degree of rotation on three different planes.
Examining a lateral view of the region, Ferrie finds that once you remove the soft tissue, the presentation is straightforward and is basic anatomy for farriers, with collateral ligaments attaching to the coffin bone and short pastern. The navicular bone is attached to the coffin bone distally by the impar ligament.
“It is important to understand these fundamental structures because their imbalance will in turn affect the coffin joint,” advises Ferrie.
If you were to look downward toward the articular surface of this area…