Posted by Patty Stiller on September 29, 2003 at 17:17:15:
In Reply to: Re: frog pressure and lameness posted by TE Couch on September 29, 2003 at 08:24:21:
: : I have been having a discussion w/ someone at my barn who is adamant that there should be no frog pressure. She cites articles that refer to studies of wild horses feet that show frogs not touching the ground - therefore, no frog pressure. This seems counter to what I had learned in an anatomy/biomechanics class and also it seems counter intuitive. Shouldn't the frog be flush w/ the plane of the bottom of the hoof in order to add cushioning and aid in circulation processes? Any opinions? Pat
: The feral hooves I have seen appear to have the rear part of the frog on the ground - then depending on terrain and weight bearing further parts forward would be involved.
: Maybe she is talking about Gene O, hooves which were painted and placed on a board showing contact in a non weight bearing state? This would not show how a hoof bears weight or what part if any of the frog would bear weight. If this is what she is referring to she should go back and read more as I understand a large goal is to get the rear of the hoof including the frog weight bearing - Patty may chime in here.
: TE
The studies that were done by Gene Ovnicek clearly showed consistant frog contact, as well as the contact with the sole pillars and the heels.There were paint marks on the rar of the frogs in al but the long feet from soft ewnvironment,s byut remember that the long feet sink into the ground every step and thereby load the sole and frog. I know of no studies on live feral fet where the frogs were not contacting the ground.
Jaime Jackson's first book does show some dead, dried up feet that the frogs are receded into the foot some, but then contradicts himself when he later uses pics of live feet in which the frogs are large and clearly down to the ground.
As well a lot of very modern studies on domestic hoof function have illustrated the vital importance of frog support to the entire rear of the foot, for shock absorbtion, circulation, and more recently the importance of frog suport in the alignment of the coffin joint and navicular bone. .
And please note the difference between frog 'support' and frog 'pressure'.
Support is when the structure is loaded and unloaded as the foot moves, but pressure is an unrelentimng pressing, such as from a mis-applied heart bar shoe or a stone in the foot.
For a good explanation about the importance of frog suppoert which is based on domestic hoof studies, try to get a copy of the Feb 2001 Equus magazine, the title article is "Hooves Under Ptressure". It explains a lot of this very clearly with good diagrams. It is a laypersons version of Dr Bowkers study, which was funded by AQHA looking for some ansewers to navicular syndrome. The importance of frog support turns out to be a big part of that whole picture.
Patty