© Rob Edwards
published in ANVIL Magazine, April 1997
Part I of a Two-part Interview
G.F. "Andy" Anderson
ANVIL: Both of you are from Oklahoma, and have just completed a lecture at the Charles Heumphreus Lecture. Dr. Anderson, how long have you been a veterinarian?
ANDY: I graduated from veterinary school at Oklahoma State University in 1975.
ANVIL: You currently are in private practice with an associate?
ANDY: Our practice is in Broken Arrow, Oklahoma, a two-man equine practice that deals primarily with performance horses.
ANVIL: Bill, how long have you been shoeing at the clinic?
BILL: The last eight years or so.
ANVIL: This year the Charles Heumphreus lecture was different from previous years: it was split into a lecture for the first half and a wet lab for the second half. In addition, two people of different professions - the two of you - jointly gave a presentation on your work together. It was obvious how well you two work as a team. I think at one point, Dr. Anderson, you mentioned that you believe it's an indispensable asset to have a farrier with whom you can work if you are an equine practitioner.
ANDY: Absolutely. I just don't understand how equine practitioners can possibly get along without farriers with whom they have a very close relationship. Back in the old days before we had Bill, we would work up a lame horse, document what needed to be done in terms of farrier science and then send home written instructions. A lot of the horses we see are referral lamenesses from out of town, so we had no idea who would receive these instructions, what their level of expertise was, or anything else about them. People would get back to us and say, 'We took this over to someone who did exactly what you wrote down and the horse is not any better.' We'd get them to bring the horse back and what had been done was not even close to what we had asked for.
ANVIL: Bill, you've been on the opposite end of that prescription. I can appreciate how difficult that can be.
BILL: Coming from Andy, it isn't. But if you're talking about a prescription from another veterinarian, that's a problem. I'm spoiled working with Andy because we are both on the same wave length when it comes to what we think needs to be done for a horse. Unfortunately, some of the other vets aren't as knowledgeable regarding some of the procedures and methods we follow. Often they will ask me what I think, and then sometimes I'll do what they suggest. It's spoiled me, however, working for Dr. Anderson. There are many good vets in our area, but some haven't stayed up on things as well as he has.
ANDY: After Bill's kind words, I must tell you that it works the same the other way around - it is so rewarding to say, 'Bill, we've got a horse that needs to have its toe backed up and needs to be shod with egg bars, for example, and know that it's exactly how it is going to get done. You just can't imagine how much fun it makes it to practice when I can just send the horse out there and say, 'Bill, here's what's wrong; here's what the radiographs look like; here's what I think, and what do you think?' And it's a done deal. There's no worry. I already know how this horse will be taken care of by Bill. So it's a mutual admiration society, believe me.
BILL: Part of it, too, in our area, is that about 90% of my clientele are also his clientele as well. That's a help.
ANVIL: Do you have a place right there at the clinic where you shoe?
BILL: Yes, it's a covered area and I have all my tools right there.
ANVIL: Well, if you can both be on site at the same time that simplifies the situation.
ANDY: I'd like to put in a plug about the advantages of tending these horses at the hospital. Not only is our facility and environment better in some cases, but if you have one that is very difficult to work on and there are two veterinarians on duty as we have, one of us can always run out and help with a problem situation if need be. The horse's radiographs and whole medical history are right there available if Bill needs to look up something about the horse in its file. It just adds more professionalism to the situation, particularly if you're talking about these intricate cases and situations. I think it's best done at the hospital, by far.
ANVIL: There's nothing better than both vet and farrier looking at the radiographs at the same time. Dr. Anderson, you mentioned in your lecture that you felt one of the problems we have is that often the veterinarians and the farriers don't attend the same lectures together, so they come into the relationship from differing angles instead of a mutual viewpoint.
ANDY: Before Bill and I had this very successful relationship, it used to be quite frustrating. I'd go off to a meeting and I'd learn some neat new technique to try on a horse's foot. I'd come home just burning with enthusiasm to try it. I'd talk to one of our local farriers when the case arose and I'd want to try this new deal that I was excited to do, but the local farrier had never heard of it. They just weren't willing to stick their necks out, either. The same thing has happened to farriers. They will go to an AFA convention or a clinic and get exposed to a technique that their particular local vet has never heard of and has no idea what they're talking about. So there again, the veterinarian in that case is very reluctant to let him try it. And that type of scenario really holds us back and keeps us from being progressive and trying new things. I think these joint meetings of veterinarians and farriers just has to be the wave of the future.
BILL: It's a lot of fun this way and enlightening, too. Andy and I have been to several meetings together and it's really helpful to then bounce things off each other, as well as weed stuff out.
ANDY: When Bill and I are sitting in the audience side by side such as at the Laminitis Symposium and someone is up at the front giving a paper, we can sit there and think, 'Golly, what do you think of that?' We might have a horse in mind at home, and we discuss if the new technique or treatment would work on that horse. We both get exposed to the information at the same time, and we can bounce ideas off each other. Maybe Bill knows the speaker; I don't. Or it might be the other way around. That way one of us will be more apt to speak up and ask questions of the presenter. I think the dialogue and the communication is much better all the way around when the two of us are attending together.
ANVIL: It's certainly the ideal but practically speaking, it's difficult to pull off. Although Dr. Ric Redden has attempted in the past to have meetings similar to the Laminitis Symposium in different areas, logistically it was very difficult. Perhaps more farrier associations could try to get the farriers and veterinarians together. It's more difficult for the veterinarians, I would think, to get farriers to attend some of their conferences on the state level.
ANDY: It depends on the program. If the program is designed with both groups in mind, then both will attend in greater numbers. At most state veterinary meetings, there is not a lot there for farriers. Even at most national veterinary meetings there is not anything presented of interest to the farrier. I think more schools, student chapters of the AFA, and more state farrier associations need to get involved jointly with the veterinarian/farrier concept - do it on a more local level - for instance, northern California, and another in southern California.
ANVIL: Now that would be interesting. It would be great to see that type of event take place at more schools of veterinary medicine.
ANDY: We gave a presentation that was hosted by the student chapter of the AAEP in Illinois. We also gave one in Oklahoma at Oklahoma State University at their veterinary school with well-known farrier, Dave Duckett. It was a combined veterinary/farrier conference. It had a lecture and a wet lab also. They went over very well, especially with the farriers. As a matter of fact, that, along with renowned farrier and competitor Grant Moon's skilled instruction, was what really pushed the Oklahoma farriers ahead of where they had been.
ANVIL: From your lecture this morning, one thing I found interesting was your discussion about the undershod horses and how they land heel first, but then the toe rises before it comes back down and breaks over.
ANDY: Don't expect to see this with the naked eye, but with some slow-motion video cameras you may be able to see it; however, it really takes a research videocamera at 300 frames per second to appreciate what goes on. We're talking now about an 'undershod' horse, which is a horse whose shoe is too small. So add undershod and underslung together and we've got the problem magnified. These horses actually teeter-totter on the heel end of their shoe. Their foot is entirely out in front of their limb. When they land, there's no shoe back behind the caudal part of their foot to support them; all their weight is behind the heel of the shoe, so they break backwards just like a horse with a ruptured deep digital flexor tendon - the toe flies up, momentum carries them forward, and the toe slaps down. They then break over and go to the next stride. But being able to watch that on slow-motion video is a major eye opener, and it darn sure will keep you from ever short-shoeing a horse again.
ANVIL: It sounds like there's at least twice as much activity of the deep flexor stretching as there is in the toe.
ANDY: We have to remember, though, that tendons can't stretch. Basically what happens when that coffin joint really hyperextends and the toe flies up, the forces placed on the flexor surface of the navicular bone are amplified many, many times more than what they were ever designed to withstand. Then you get into Roy Poole's theory regarding the pathogenesis of navicular disease, and it answers the big question of where all these navicular-diseased horses come from. Roy is a pathologist at the University of California at Davis, who, in my opinion, is brilliant. He came forth with this theory regarding why horses get navicular disease. He exploded a lot of the prior myths on the same subject.
ANVIL: Speaking of people here at UC Davis in California, you referred to a radiographic view as 'Dr. Tim O'Brien's view.' Dr. O'Brien is the one who organizes the Heumphreus lecture. Could you tell us something about the uniqueness of that view?
ANDY: The 'Tim O'Brien view,' as I refer to it, is where the x-ray machine is behind the foot up above, shooting down at an angle, and you actually get to see the navicular bone stuck out by itself as opposed to having it superimposed on the pastern.
ANVIL: That must be exremely valuable in diagnostic work. Now, back to the long toe/low heel syndrome, Grant Moon mentioned that the toe actually drags the foot forward and the heels collapse.
ANDY: I'm not sure that's the best way to phrase it. I have to give Grant a lot of credit because he is the first person who got me thinking about the cause of these crushed, underrun heels. In the past, we concentrated all our efforts on the heel. Grant said we were looking at the wrong end of the foot because of the way this all happens: the toe gets farther and farther out in front, creating a longer and longer lever. That makes the whole base of support farther and farther from the limb. The longer the lever arm you stick out in front, the more you pry the horse back under its heels. Unless you continue to add more shoe length behind the horse, you just keep moving its base of support farther and farther in front of his limb. So until you move the entire base of support - the whole shoe - back, you have really not done the horse a service. The only way to do that is to get rid of the long toe, get rid of the underrun heel and move the base of support back.
ANVIL: Another interesting part of the lecture was how you said that you shorten the toe from the coronary band down and that you generally don't take much toe off the bottom of the foot at all.
ANDY: Yes, but I'm not sure that's the best way to phrase it. Not from the coronary band down, but we shorten the toe from the dorsal surface of the hoof rather than from the solar surface of the hoof. Rather than cutting it off with nippers, which goes deep into the sole, we just back up the toe in the front with a rasp.
ANVIL: For many farriers, the idea of curing the long toe/low heel syndrome by not taking toe off the bottom is incongruous. But your slides indicated that by going after those heels and encouraging the heels to grow in the proper plane instead of in the underslung position, you move the base of support back where it needs to be.
ANDY: It isn't that these heels are too short, but that they are growing in the wrong plane. By allowing them to get longer and longer, you don't improve the plane; all you do is allow them to grow them further and further forward. You can cut off all that underrun foot back to where it needs to be, move the heel back where it belongs and then try to get it to grow down straight. That's how trimming the heel to stand horses up can make a lot of sense.
ANVIL: You also said you didn't find that wedge pads did much good, and you indicated that the aluminum wedge shoes gave better results.
ANDY: Yes, but we use those very rarely. We probably have only three horses wearing wedges now.
ANVIL: So by extending the shoe back, you are elevating the heel.
ANDY: It's the toe that we've simply got to address. If you leave all that long toe on and cut off all the heel, that will probably hurt the horse. So doing one without the other doesn't make sense and is a big mistake.
BILL: The first horse we trimmed today didn't need a wedge. I cut a lot of heel off him and didn't need a wedge at all after we finished, because we had moved his base of support underneath his leg.
ANVIL: There are rocker toes and rolled toes and setting the shoe back and other different methods. But your method of choice is the rocker toe. Why is that?
ANDY: It does so much more than the rolled toe. You move the breakover back much further than you did with the rolled toe. Plus you get that clipped effect that you don't get with the rolled toe.
ANVIL: Clipped effect - you mean the shoe is more stable on the foot? The rocker toe is a little more difficult to fit, though, than a rolled toe. But you feel it's definitely worth the extra effort, then.
BILL: I think so, but it doesn't really matter. If you rasp too much and you have a little gap there, it's not going to make a difference. The only thing that would make a difference is if you trimmed a little too short. Today I backed both those horses almost to the white line. Over a period of time, keeping a horse's foot backed up will thicken the wall. It comes right back and the foot grows in a normal plane after that. Many people are worried that the way you thin the wall so far out, there's not enough wall in the front anymore. That's true the first time or two that you do it. But as the foot grows out, the wall gets thicker and it comes back normally. I don't know why, but it does.
ANVIL: With your method of shoeing, you're establishing a platform for the foot to grow toward, eliminating the extended toe in the front, and encouraging growth of the vertical heel. In your demonstration, Bill, you purposely left a gap between the shoe and the foot. In conjunction with that, Dr. Anderson, you refer to a 'jammed coronary band.' Could you explain that?
Note the gap between the hoof
wall and the shoe in the area of
the jammed coronet band, as
evidenced by the rings
on the hoof wall.
As you can see in this photo,
which was taken about an
hour later, the hoof wall has
already migrated downward.
ANDY: I think the simplest way to put this is where the coronet band is jammed proximally, you need to remove that much foot with corresponding solar area of the foot. Follow the tubules; don't go perpendicular to the ground. Follow the horn tubules and cut that same kind of little crescent at the bottom (see photos to the right).
ANVIL: Bill, you mentioned that portions of the hoof wall will pull down to the shoe within 24 hours.
BILL: Yes, that's right. It really depends on the moisture content of the foot, I believe. The hoof will settle down to the shoe.
ANVIL: It shows how those tubules slide vertically against each other.
BILL: To me it's geometry - the way all that happens because of the angles of the outside of the hoof wall and then the angle that you rasp. And whenever you pull all that back down, it doesn't just come down at the same angle of the hoof wall. I feel that it is pulled down and in. And that's how you will lose the flare on the outside - the wall isn't pulled down to the angle; it is pulled down in to the shoe.
It also depends on how long the horse has been in this condition. If he's been in this condition for ten years, then it's likely it might take several months. I've had some that are able to be fixed right away, and then I've had some that are fixed in six months, and some of them, every time I shoe them I dip in the inside heel quarter or the outside toe quarter and nothing happens. And then two years later I'll be shoeing the horse and see that it's fixed! I'd forgotten about it, but it's fixed. That happens particularly in the hinds. The fronts are a lot easier to fix than the hinds. But it can even take up to a couple of years for some of them.
ANVIL: The foot is a marvelous thing, very formable.
ANDY: It remodels in response to the forces placed upon it. I like to think that we're placing forces in a more physiologic fashion than the force that is placed on it by a long toe/underrun heel configuration. If you leave hooves in that long toe/underrun configuration, they get worse. Then you stick a wedge pad in there to jack him up and he doesn't get better. In two more shoeing intervals, you'll need to put in two wedge pads because it's gotten worse.
The thing that sold us was the first time Grant Moon came to the hospital. We had a large Warmblood horse that I had shod with wedged aluminum eggbars. The eggbar shoe was an inch thick across the eggbar, tapered to 3/8" at the toe. That's a pretty radical-looking device, right? And we were happy - this horse was sound. Grant looked at this horse and just laughed. He said, 'I see what you're doing, but have you had to add more wedge as time went by?' We told him yes, we had. He asked, 'Where are you going to quit? If I come back in a year, are you going to have a two-inch wedge under there? There's a point that we can't go any further.' I replied, that's why he was here; we were reaching that point rapidly. This was before Bill and I were good friends and before either of us were believers. Grant said, 'I'm going to leave your device on one foot (on this horse, both front feet were just alike). I'm going to pull a shoe off and trim the other foot. When I get through trimming, it will be more stood up than the one with the inch wedge.' And we didn't believe him.
Grant pulled the shoe off and backed this horse's toe up, trimmed to the widest point of the frog, and set his foot down. That foot was more stood up than the one with the one-inch wedge. That was the most dramatic strategy I've ever seen. Our goal became to trim horses so well that we don't have to do any fancy blacksmithing.
Part II of this interview will appear in the May, 1997 issue of ANVIL Magazine.
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