Hoof Testers "How To"

The subject of hoof testers comes up frequently among farriers and veterinarians. I recall teaching an equine podiatry electives course at Cambridge University in the United Kingdom many years ago with a dozen sixth year veterinarian students in attendance. They were very interested in learning about the foot's anatomy, but what really peaked their interest was learning how to use hoof testers properly. Apparently they were under the impression that many vets suffered back injuries from not positioning themselves correctly under the horse while using hoof testers. This post is not about getting under the horse correctly, but it is very important that you do get under the horse when using testers. It is difficult to feel response if you are holding the hoof with one hand and the testers with the other. You need to be under the horse with the limb in the correct trimming position, so that you may use both hands on the testers. I will be posting a video in the near future on how to get under the horse correctly for tester use.  

There are many types of hoof testers that can be purchased. At our school I recommend a hoof tester with a spring gauge, that allows the student to develop a better feel for its use. 

Spring Gauge Hoof Tester

The key to using hoof testers correctly is to be consistent in the amount of pressure applied over each area you wish to test. Where many texts suggest that hoof testers are used to pinpoint pain, I suggest that you begin to develop a feel for their use. The amplitude of a response can tell much more than simply the location of pain. Response can tell you what structures are involved, to what extent the damage might be, and just how much can you do to alleviate the pain. They will help you to determine if further imaging may be required, or if it is simply a matter of time that is needed to heal the problem. Learn also how to communicate your findings to the attending veterinarian. At our school we note hoof tester response on our Spectrum of Usability.

On this form we note response on a scale of 0 to 3, with "0" being normal. When the response is very slight it is noted as 1/3, when it is moderate 2/3, and when it is severe 3/3. The rating scale is used for rating digital pulse as well. I also mark the location of the response on the illustrations at the bottom of the form. I recently attended a farrier and veterinarian conference in France where a farrier was presenting a lecture on the Spectrum of Usability and the first slide on his power point was this image. It is good to know that other farriers are recognizing the need for documentation to help in our communication with the veterinarian.

Here is how you can develop your hoof tester skills.

Suggested Exercise

First it is important that we establish a base line of response. Going directly to the foot we believe is causing the lameness may solicit a response, but this does not tell us the severity of the problem. Like a lie detector test, we must first establish a line of questioning to determine the level of comfort for this given horse. Some horses are very sensitive to the pin-point pressure of hoof testers, but move soundly on the line or under saddle. Where others give no response to testers, yet expel an abscess in the next 48 hours, you never know. I find it best to try and eliminate the variables in most everything I do, and with the use of hoof testers is no different. 

The procedure of being selective as to which hoof to begin helps in determining if a compensatory lameness exist, along with what first appears to be the primary lameness in the foot. I will note how the horse offers up each limb, and how it reacts to my manipulations, as compensatory lameness may manifest itself in muscle or joint and certain movements can trigger an unexpected response.

Starting on the hoof that is farthest from the limb suspected of causing the lameness, I use the following procedure. Example: If the right front is suspect I begin on the right hind, as the left hind (diagonal lameness) is most common in compensatory lameness. I then go to the left fore (bi-lateral lameness would be the second most common), then to the left hind and finally I go to the right fore the suspected foot.

Begin using your hoof tester to test the sensitivity about the distal border of P3. Applying mild pressure at 1 o’clock, 12 o’clock, and 11, o’clock. Stay consistent with the amount of pressure applied to each point. Next, apply pressure diagonally to the fog as pictured below.  This move places pressure on the Navicular apparatus. You may also elect to apply pressure diagonally to each bar, and to the seat of the corn in the same fashion. In all the described moves attempt to keep the outside jaw of the tester (the one applied to the hoof wall) as low as possible on the hoof wall. If you solicit a response to any of these points, make a mental note and continue your hoof tester evaluation. When finished I make record my findings on the Spectrum form. I do not offer a response to the handler or owner while under the horse. Often a horse will appear to be offering a response to the handler or owner only to have the response solicited by a fly or protest to your manipulation. You should wait until you have completed your evaluation before offering any comments.

Practice this procedure often. I recommend that a base line of reading be taken on all first time visits. It helps in determining the current state of health.

A note of caution, never apply excessive pressure with testers. You are not trying to cause pain, you are trying to determine if there is pain. The spring gauge hoof tester applies between 50 -75 pounds of pin point pressure when brought to the first line. I recommend that you start there and develop a feel for the tool. Experience will help you determine how to best use the tool.