Monday, 16 July 2012

Corns

It was only a matter of time before I posted on this topic. Most greyhound owners are at least aware of, if not well acquainted with the tricky affliction that is corns. Eddie has been spared this malady, but Cassie has had a couple of mild corns previously.

The first signs of a corn is usually lameness on hard, but not soft, surfaces. Corns appear as round, sometimes whitish, domes or discs on the paw surface. Although it is said that corn are often misdiagnosed as skeletomuscular problems, I have found that vets often are aware of the problem in greyhounds. It is worth considering corns when faced with otherwise unexplained lamenss, and dealing with them as soon as possible, since they can lead to secondary problems, as the dog modifies its gait due to the pain.

Examples of corns on
greyhound footpads.
Commonly thought only to occur only in greyhounds, corns, or circumscribed hyperkeratotic lesions, are found in other breeds too. However, it does seem that they are most problematic in greyhounds and lurchers, due to the lack of cushioning fatty tissue in their toe pads making the condition more painful. In fact, it is also suggested that this lack of fat is one of the reasons greyhounds tend to get corns far more often than other breeds.

Viral infection and foreign bodies in the pad are also cited as possible reasons, but mechanical pressure is likely to be if not a causal then at least a significant contributory factor in the formation of corns. Corns usually develop in the centre of the two middle, weight bearing, toes of the paw, and more commonly on the front paws, which take the most weight in a greyhound. This seems to indicate that pressure on the pad from the toe bone is crucial to the formation of corns in greyhounds. 

In humans, corns usually develop on feet due to mechanical pressure, such as ill-fitting shoes or protruding bones. The difference between corns and the simple thickening of the skin known as a callus, is that in a corn a hard plug of keratin (skin tissue) is formed, pressing into the skin and underlying nerves, making it potentially very painful when under pressure. Corns are fairly easy to remove in humans, but tend to recur. 

I have been previously been able to deal with corns on Cassie's paws myself. I soaked Cassie’s foot in epsom salt solution (traditionally used to “draw out” corns, foreign bodies and infections in humans as well as horses and dogs), and then filed down the skin on the pad until I could see the corn kernel clearly. When possible I then hulled the corn using a large gauge surgical needle (which works as a little sharp spade). Sometimes would have to soak and file the foot a few times, with a couple of days break in between, before being able to get the corn out. One corn came out on its own, during a walk, after a few times soaking and filing.

Many vets will use a similar technique, working the corn out with a scalpel or a dental root elevator. Often this can be done without much discomfort to the dog, but vets can and do sedate some dogs to make the procedure easier.

The dental root elevator technique. Click to enlarge. 

This time, however, my usual technique didn’t work. There was hardly any sign of the corn on the pad. This looked more like a lesion from a bit of glass or something. I managed to extract some corn tissue from the site, which did seem to alleviate Cassie’s lameness somewhat each time. I kept on having to repeat the procedure though, without being able to extract the whole corn kernel.

The vet advised that surgical removal would probably be necessary, but I chose to wait a couple of weeks, as I was going away and did not want to leave post-op care to the people looking after my dogs. When I came home, Cassie was much worse, however. She was almost constantly lame on the leg, even in protective booties, and even on soft ground.

Cassie was also getting pretty sensitive about me touching the foot. Usually she is quite patient and allows me to bother her corns with minimal grumbling. Now she was screaming and snapping. She was obviously in quite some pain. It seemed clear that surgical removal under general anesthetic was the way to go.

The operation was fairly quick – she was under for less than half an hour. However, the corn removed was a whopper, and deep. It had grown inside the pad, and trapped nerves against her toe bone. No wonder she was in pain. Her pad had to be stitched together with non-dissolvable suture, which will stay in for two whole weeks. She is on-leash only for this time, too, making sure the pad gets to heal.

The excised corn. Note how far below the
hard skin of the pad the corn extends.

The stiched pad. 

I am not sure why this corn grew – or moved? – inwards, into the flesh of her toe, when many grow outwards, in the harder outer layer of the pad, making them easy to remove. I wonder whether my interference had anything to do with how the corn developed. Ilaria Borghese, president of Thera-Paw and guru on corns, in her widely consulted article, also suspects intervention may be detrimental to the development of corns, especially if using salicylic acid products marketed for human corn removal. 

I have indeed considered but decided not to try these products, because I am worried I’d do more harm than good. There are also reports of a successful technique using duct tape, but I have not tried this. In my opinion, considering the that mechanical pressure seems to be the best contender for the cause of corns in greyhounds, perhaps prevention is better.

If the theory that the lack of fat in the greyhound foot pads causes corns is right, then we could say greyhounds have ill-fitting paw pads. Like in humans, corns will recur if the pressure that caused them in the first place is not dealt with. Unfortunately, unlike shoes, paws cannot be changed for a softer, more comfortable pair. The problem of corns, if a dog is afflicted by them, is therefore usually chronic or recurring. Whatever way you treat the corn, if the underlying mechanical cause is not addressed, they will most likely come back. The long term success of surgical removal is not very good - over half of excised corns return one to three years after surgery according to a study - so I am half expecting Cassie's corn to reappear at some point, although I will try to prevent it. 

The easiest way to prevent recurring corns is to use padded shoes on dogs with a history of the affliction. The best ones I have found are the Thera-Paw boots (for UK distributor click here). A more drastic measure is to partially or completely amputate the affected toe. Some studies have found this to be more successful than any surgical removal of corns, while others report that corns return on remaining toes (which presumably now take the pressure when the dog moves). An experimental treatment involving the implanting silicone gel cushions in the pad has been tried but doesn’t seem to have moved on to any clinical use in canines.
I expect the gait of individual greyhounds, which affects how weight is distributed on their pads, is relevant to whether any particular hound develops corns or not. I wonder, therefore if correcting other possible skeletomuscular issues, using pain relief, physiotherapy and other relevant therapies, may aid dogs with recurring corns. 

As Cassie has a history of corns, and the recently removed one is likely to recur, I am thinking of having her wear her Thera-Paws any time we walk for any length of time on hard surfaces, taking it off only when she has a run-about on grass (they don't tend to stay on when she reaches 5th gear!).

I know many greyhound are affected by corns, and would love to hear from you if you have any experience with corns. Any miracle cures? A novel way of preventing corns? Please leave a comment!


Sources and Links:


Carol L. Machery, William E. Feeman III, (2006) Using a dental root elevator to remove footpad corns in dogs: Two practitioners' experience, Veterinary Medicine, December 1, 2006. Access online: http://veterinarymedicine.dvm360.com/vetmed/Medicine/ArticleStandard/Article/detail/392957

M. J. Guilliard, I. Segboer, D. H. Shearer, (2010) Corns in dogs; signalment, possible aetiology and response to surgical treatment, Journal of Small Animal Practice 51, 162–168

S. F. Swaim, T. Amalsadvala, D. B. Marghitu, E. A. Sartin, J. A. Hudson, E. D. Stoenescu, Pressure Reduction Effects of Subdermal Silicone Block Gel Particle Implantation: A Preliminary Study, Wounds 16:10, 299-312.

13 comments:

Adam Normandin said...

My girl Olive had a pretty bad case of corns. Both her rear paws and one front. We tried all the methods mentioned in your blog, but nothing worked. There is a remedy by a pharmacy in Pittsburgh called Murray Avenue Apothecary. Many excellent reports on this if you search the internet. We tried it ourselves, and the corns did improved drastically, but did not resolve entirely. Then we found a homeopathic practitioner in Ireland named Lori Rose. Homeopathy works by stimulating the immune system so the body heals itself. Having nothing to lose, we gave it a try. Olives corns began to disappear within weeks of this treatment. Now she is completely corn free. ...Quite miraculous actually, considering all the dreadful reports I have read about this condition. Olive no longer limps or needs the therapaw booties at all now. Lori has helped many greyhounds with this problem. You can email her for more info: lorimrose@aol.com -Good Luck!

E.A. said...

Hi Adam , thanks for the comment and the recommendation. Always been skeptical about homeopathy but if the corns keep coming back, as you say, there is nothing to loose by trying!
Glad to hear Olive is rid of the corns, they do blight the lives of otherwise healthy dogs.
e

Adam Normandin said...

Hi E,

Yes, I can relate to your feelings about homeopathy. Until I found Lori, I had no experience with it myself. If Olive's toes weren't in such bad shape, I never would have considered it. As I mentioned, we had gone through all the various other treatments without much success. -At least not enough. After a year of the Murray Avenue treatment, Olive did improve quite a bit. Two of her five corns resolved and the others shrank, but my girl was still having a hard time walking. It was really heartbreaking to see her struggle. We had been to three different vets and it seemed that I knew more about this condition than all of them combined. Out of frustration, I decided to give Lori a try. I did some homework about homeopathy first, and it is actually quite a valid option. -Been around for long, long time. It is gentle and has produced some truly remarkable results for conditions far worse than corns. I have read that greyhounds in particular tend to do well with such treatment because of their in metabolisms. Anyway, I really don't mean to sound like a salesman. I'm only sharing my experience with you and hope that it might offer your hound some relief. Believe me, I know all too well how frustrating corns are. You might consider the Murray Avenue treatment if you are more inclined to go with conventional methods. Perhaps if I were more patient, it would have completely resolved Olive's corns. I'm sure it all depends upon how bad the condition is.

Julie Higham said...

Hi there. I'm involved with Wimbledon Greyhound Welfare. www.hershamhounds.org. Our vet Daniel Doherty has developed a noninvasive method of dealing with corns whereby you go back 3 times for him to excise the corn,apply a paste and bandage the foot then you continue for another 2 weeks at home filing and applying tincture and oil. It has not been 100 per cent successful but very nearly ! He is a brilliant greyhound vet if you can get to him at Uxbridge, Middx. His surgery is myvet24/7 and he's perfectly happy for you to go just for the corn treatment. Very reasonable too, about £100 in total.

E.A. said...

Hi Julie, thank you for your comment. I have heard of Daniel from several greyhound owners. Certainly if Cassie's corns return I would try him.
Cost has become an issue as the insurance rather annoyingly has now excluded any skin issues on all her paws - as she had a diagnosis of corn previously (one that I managed myself!).
Despite long recovery from the surgery she seems fine now, and I am using a bootie on her if she walks on tarmac for long walks - fingers crossed the corn will stay away!

B said...

I am currently working with my female greyhound to get used to the Thera-Paw. She had her 4th toe on right front leg amputated due to an old race injury. I'm concerned because the 3rd toe now lays flat, and at times she prefers to walk on grass which isn't her style. We've made some progress using high value treats and walking fast or else she hops and won't step on it. Or else worse she chews it! I hope it helps.

E.A. said...

Hi B, thanks for your comment.
In my experience greyhounds tolerate the therapies very well. If you don't have any progress with getting her used to it, I would have a vet look at the foot again - she may be getting some kind of secondary problem - that third toe sounds a little odd. Has she dislocated it somehow?
How long since the operation? If she is still healing, I expect it is just very uncomfortable still...
Good luck, E

Linda in Colorado said...

i have a chinese crested with this condition. the corns on his back feet are very bad. I've tried the creams from the vet and saw no change...anyone else with breeds other then greyhounds seen these issues. Can you tell us what the homeopathic treatment was?

Simon said...

Another recommendation here for Daniel Doherty in uxbrige. Our whippet Alfie had been suffering for a year with corns and had no success with surgery from our local vet. We had got to the stage of not being able to walk him on hard surfaces, and he was even struggling on wooden floors indoors. We took him down to Daniel in January, and he is now fine, walking perfectly on hard surfaces. The treatment really does work.

Sonja Garofalo said...

Hi. I have a whippet afflicted with corns. My question is how long do you soak the feet in Epsom salts ? My whippet doesn't like getting his feet wet so this is a bit troublesome. Would using a moisturizing lotion or Vaseline help to soften the tissue?

Sonja Garofalo said...

Hi. I have a whippet afflicted with corns. My question is how long and often do you soak their feet in Epsom salts? My whippet doesn't like getting his feet wet so soaking is quite an issue. Also, could I use a moisturizing lotion or Vaseline to soften the tissue? Thanks for your help.

E.A. said...

Hi Sonja,

You could make a poultice of cotton wool soaked in epsom salt solution and apply it to his foot in a boot or secure it with vet-wrap or similar bandage. You'd have to leave it on for a while, but it has worked for me before.
Using vaseline etc will soften the tissue as well, I guess, and can't hurt if you'e using non-perfumed stuff. The good thing about epsom salts is that the seem to "draw out" the corn core.
Good luck.

Eva

Jo said...

Hi there. I have a 9 year old golden retriever who is suffering from a corn. This is the second time he's had to have it surgically removed. It affects the big pad in the middle of his front left paw. He has been very lame with it. Having had it removed the first time (said to have occurred due to viral infection of a wound) it took 6 months to heal & came back in two years. We've just gone through the whole process again. I'm thinking of boots for him. Its possibly a silly question but should I just have a boot on the affected paw or should he wear boots on both front paws so as not to affect his walk? Thanks