(featured image from anatomy-of-the-equine.com)
This week covers a very important landmark ...
I call it the 'Hairline" from Lyle "Bergy" Bergaleen's "The Hairline Tells It All"
The Hairline is the Coronary Band.
(You can get Bergy's 2nd edition of the book on Amazon. I can't tell you if its at all different from the edition I read back in 1993 ... but will order his new edition when I get done here!)
Linda Harris describes what happens inside the hoof capsule when the hairline is distorted.
I've explained, over the years, to hundreds of students about the hairline and how much it can tell you about what's going on inside the hoof ... in the foot. It truly is a MAJOR landmark as to the overall balance of the hoof. One can actually WATCH the hairline/coronary band 'relax' when pressure is removed and the horse walks out from the trim. Combine the hairline clues with the overall shape of the hoof, the frog, the heel bulbs and more and one can make a pretty good assessment of the health of the foot inside the capsule.
The coronary/hairline is highly maleable. That is, capable of being shaped by pressure.
One thing that is important to realize -- when the hairline/coronary is jammed up then its circulatory system is also compromised. The coronary band provides the majority of nutrition to the hoof and is the area from which the hoof grows. Inside the coronary band is the coronary corium. This tissue is full of blood vessels that feed the hoof wall. The blood vessels feed the foot for growth and if the foot isn't getting fed properly then the horn growth cannot be optimal. Therefore, it stands to reason that the entire foot and hoof will be damaged in some way.
The papillae, long, hair-like projections of the coronary band [#1 in left photo that fit into the coronary groove #1 right photo], deliver nutrients to the hoof wall through horn tubules (laminae) [#2 in left & right photos], which grow from the coronary band to the ground. Other cells containing keratin grow from the sides and base of the papillae and effectively glue the horn tubules together creating what’s called intertubular horn. This framework is what gives the hoof its strength and elasticity.
When the coronary band is damaged, the entire hoof structure is compromised.
How does this happen? There can be various reasons for the coronary band to be damaged but, the most common is, in short, the hoof is over-trimmed and improperly trimmed. The heel buttress is over-trimmed or, in some cases, entirely trimmed out and the hoof collapse begins. The quarters collapse, the sole thins as the toes and horn begin to run forward but, at the same time begin to jam up the coronary band ... well, Linda explains much better than I.
This video done by Linda J. Harris of "The Happy Hoof" explains it all very well. ...