Anatomy and Fractures of the Coffin Bone

Unfortunately, coffin bone fractures are not all that unusual with the horses that many farriers work with on a regular basis.

While all breeds of sport horses experience this injury, they tend to occur more frequently in jumpers and Standardbred trotters and pacers. Farriers will find that these nasty injuries are often a major concern with horses working on hard ground or running on a hard track.

To fully understand how fractures of the coffin bone — or third phalanx — occur, it’s critical to first understand the anatomy of the equine foot and the stresses placed on the horse’s leg under many different circumstances.

That’s why we’re offering you a 20-page technical analysis of coffin bone fractures and practical approaches to treatment in a new American Farriers Journal special eGuide, “Anatomy And Fractures Of The Coffin Bone.” You can immediately download this valuable in-depth eGuide, featuring 20 full-color illustrations and figures, and keep it on your computer or store it on your mobile device for quick reference and/or teaching with your footcare clients.

Dear Hoof-Care Professional,

Even with the most balanced trimming, an excellent training schedule, a good working surface and excellent hoof care, coffin bone fractures cannot always be prevented. Yet, to be successfully treated, it will take a full team effort made up of the farrier, horse owner/trainer and veterinarian.

Understanding The Structures And Stresses Of The Foot Is Essential

With a full understanding of this eGuide’s in-depth analysis of anatomy, you’ll be well ahead of the pack when it comes to dealing with coffin bone fractures and injuries. Thanks to this 20-page eGuide, you’ll gain considerable knowledge from an extensive review of the major anatomical structures that make up the equine foot. 

There’s a full explanation of the hoof capsule and the laminae that connect to the distal phalanx or coffin bone, the coffin or distal interphalangeal joint, the digital cushion, the navicular bone, the navicular bursa, critical ligaments, the insertion tendons of the common digital extensor and deep digital flexor tendons. Plus, you’ll learn why having a complete understanding of the lateral and medial cartilages and associated nerves and blood vessels found within the foot are also essential. 

Having a full understanding of each of these anatomical structures is critical for dealing with coffin bone fractures and injuries. In fact, even if you don’t normally see any coffin bone fractures in your footcare practice, this eGuide’s extensive review of hoof anatomy is well worth downloading and studying.

Excessive Down Force Places Extensive Pressure On The Coffin Bone

The coffin bone is impacted each time the hoof capsule absorbs the impact force coming from the ground. The coffin bone, digital cushion, laminae, frog and bars absorb the resulting force from the horse’s body weight moving down through the foot.

If the horse has well-trimmed feet and works on an even surface, these resultant forces should be equal. Yet if the surface is uneven, the horse is conformationally challenged or the foot is unbalanced, these forces will not be equal. There will be an excessive force or stress applied to one or all of these structures, which can lead to three basic categories of fractures within the coffin bone:  

  • Fractures in the toe region that may extend to the joint.
  • Fractures of the wings.
  • And fractures of the extensor process. 

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Studying this eGuide, you will learn that coffin bone fractures can occur anywhere within the bony structure itself. The three categories mentioned here can be further divided into six basic types of fractures:

  • Wing fractures, which are the most common fractures of the third phalanx.
  • Articular wing fractures.
  • Sagittal articular fractures.
  • Comminuted articular and non-articular fractures.
  • Chip fractures
  • And extensor process fractures.

The major cause behind fractures of the toe and wing of the coffin bone are due to stresses that are much different than other types of fractures. While direct trauma is the main cause of wing and toe fractures, the application of excessive tension on the common digital extensor tendon is the major culprit behind fractures involved with the coffin bone’s extensor tendon.

As the foot turns or twists while landing with rotational force, uneven stress is placed on the third phalanx, which will often lead to a fracture. Although trauma is the most common cause of fractures within the third phalanx, foreign object penetration, improper shoeing, unbalanced shoeing, infection and even nutritional deficiencies can also lead to fractures of the coffin bone.

Most coffin bone fractures that take place within the wings, toe or articular structures lead to a very lame horse. These resulting lamenesses occur either immediately after a race or within the first hour after exercise when someone notices the horse is reluctant to bear weight on the affected limb. Other symptoms include an increase in the digital pulse and notable heat within the foot as observed through palpation.

On the other hand, fractures of the extensor process may lead to a rather obscure lameness, such as a shortened stride.

This 20-page eGuide also looks at typical shoeing treatments and also at various surgical options. Your clients will want to avoid coffin bone fracture surgery if possible since a horse may have to be rested for as long as 6 months.

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But wait there’s more!

Besides offering a total evaluation the categories of coffin bone fractures and a complete anatomy of the equine foot, this FREE eGuide also details other valuable information that you will want at your fingertips before confronting these devastating injuries. Learn the latest:

  • Clinical signs and problems that mimic coffin bone fractures.
  • Tests, examinations and evaluations that are necessary to make a definitive diagnosis.
  • Appropriate shoeing treatments for articular fractures, as well as fractures that do not involve the coffin joint.
  • Surgical treatments for the various categories of coffin bone fractures.

This FREE eGuide offers valuable insights and techniques to better prepare you for understanding how coffin bone fractures occur, the steps to follow when one takes place and a valuable reference to explain these concerns to your footcare clients.

Yours for better hoof care,

Frank Lessiter
American Farriers Journal

P.S. Be prepared when one of these coffin bone disasters occurs by having this valuable 20-page eGuide on hand! It’s yours to download FREE right now!

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