Motor or Motion Problems

Difficulty walking with back legs in English Bulldog

Question: Hello, I have a four year old American Bulldog who has paresis in his hind legs that is progressively getting worse. The best way to describe his condition is that his rear end looks drunk. We had his spine and hips X-Rayed and looked at by both a neurologist and radiologist. In both cases they didn't see anything that might be causing this. We ran tests for Neospora Caninum and Toxoplasmosis , the Neospora Caninum test came back negative, but the Toxoplasmosis test came back with a slightly elevated levels. However my veterinarian feels that this may have been from a previous exposure and is not causing his current condition. To be on the safe side my vet prescribed Doxycline and wants to test him again in a few weeks to determine if these low levels are declining or increasing.

I have been sending email to all American Bulldog breeders I can find and have received plenty of replies, with suggestions ranging from a pinched nerve to meningitis. Also I have contacted the breeder who I purchased my dog from and he has seen this in my dogs Uncle and Aunt. He has not been able to get a diagnosis and may put his dog (the Aunt) down to have an autopsy performed (she is really doing badly). This has led my veterinarian to believe that this is a hereditary based disease and feels we won't be able to diagnose this until we can get a spinal biopsy from one of the dogs. However I received a reply to an email from a person in Washington who's American Bulldog has the same condition that they were unable to diagnose as well.

My veterinarian has been very receptive to any suggestions and has encouraged me to continue to find out anything I can. So that's why I'm writing you. Is it likely that this is genetically based or possibly even meningitis?

Do you have any suggestions or ideas?

Thank you.... Dennis

Answer: Dennis-

For a condition like this that is affecting primarily the rear limbs, a problem with an intervertebral disc, instability of the lumbo-sacral junction (cauda equina syndrome) or other spinal cord injury seems likely. The most reliable test for documenting these problems is an MRI, based on work done at Colorado State University and the University of Washington. Disc problems are often inapparent on plain X-rays and are even inapparent when myelograms (X-rays with dye around the spine) are done in some instances based on the work at the two universities. The lumbosacral instability problem is also more likely to show up in MRI or CT scans than on plain X-rays.

We have seen one or two patients that we really thought had spinal cord disorders that actually had bilateral cruciate ligament ruptures. We missed the first one of these because we were just convinced that the problem was spinal. This was in a German shepherd and she got weaker and weaker for about three weeks and then began to gradually get stronger (the owners refused surgery) and was doing well about three months later.

There was a literature reference to canine myotonia, a degenerative muscular disorder that was reported to have a higher incidence in chow chows and Staffordshire terriers (Kortz, 1989) which caused progressive muscular weakness and stiffness but this is reported to show up pretty early in affected dogs, as early as 8 weeks of age. If you were not seeing any evidence of problems until recently, this is probably unlikely. The American bulldog is one of the breeds that is sometimes mentioned as susceptible to this condition but I do not have any idea what the prevalence in the breed might be.

I will try to check to see if there are any other neuromuscular disorders that are peculiar to this breed but found none on the initial search through the literature I have here. In the meantime, if the neurologist only saw the X-rays and not the dog, it might really be worthwhile to get your vet to refer you to the neurologist for an initial examination and then decide what sort of work up is necessary from there.

Mike Richards, DVM 6/12/2001

Movement problems in Sheltie

Question: My nine year old Sheltie is having problems, probably arthritis, rigid movement. Rough shedding coat (I have him on a oil internally Lenten), tongue sticks out 1/2 to 1" at times. Think he is getting cataracts. I am a naturopath and looking for natural help for him. Thanks. Frances

Answer: Frances-

It is a good idea to try to get an accurate diagnosis of the cause of the movement problems. Arthritis is an easy assumption because it is the most common cause of problems in older pets but there are lots of causes of arthritis and the treatments vary some. In addition, there are other disorders that can lead to movement difficulties, such as spinal problems, hyperadrenocorticism, hypothyroidism, cruciate ligament injuries, bone cancer, heart disease and polymyositis. Arthritis can occur due to degenerative joint disease (the typical arthritis that people think of), from Lyme disease, from immune mediated disease, bacterial infections, systemic lupus erythematosus and other conditions. If a specific cause for the problems can be identified through examination, X-rays, aspiration from affected joints or other diagnostic tests, it is possible to tailor the treatment to the specific problem.

For arthritis, the combination of glucosamine and chondroitin helps many dogs. This is a "nutriceutical" and is usually dosed at 500mg of glucosamine and 400mg of chondroitin for every 25 pounds of body weight. (1 of the standard tablets per 25 lbs. of body weight). Accupuncture is reported to help dogs that have arthritis. If there is a veterinarian in your area well versed in the use of herbs, it is possible that there are herbal treatments that might be helpful. I like aspirin a lot for the treatment of arthritis but that might not fit into your treatment philosophy.

I can't really think of many causes of a tongue sticking out a lot. This occurs in some dogs with hydrocephalus or other brain disorders but it seems unlikely that is the case. If the canine teeth are missing it is hard for dogs to keep their tongues in their mouth entirely. Those are the reasons that I can think of for this problem but there may be others and it might just be a behavioral thing.

I couldn't understand what was happening with the hair coat. Is shedding occurring in clumps or just not occurring normally?

Mike Richards, DVM 12/27/2000

Exertional hyperthermia (sometimes exertional myopathy) in Labrador

Question: I don't think I've spelt Azoutura correctly.

But I wonder if you have any information on this condition in dogs?

Our bitch Tilly, Labrador, 4.5 years. Fit condition Taken for a walk between 3-4 pm Fed at 5 pm Left in bed for evening 6-10 pm

When we returned at 10 pm Tilly did not get up to greet us and was barely able to walk with her hind legs. We had to lift her onto her legs to get her to stand.

We visited our vet immediately who diagnosed azoutura or muscle bind and gave her an anti-inflamatory injection and glucose and electrolyte drinks. He told us to massage her when we got home which we did with Arnica, Rhus Tox and Ruta cream. Also to take her for a short walk tomorrow morning and afternoon with massage before and after.

Our vet tells us that this condition is quite common in greyhounds and can lead to kidney damage.

Do you know what can be done to stop this reoccuring? She had a lot of exercise Monday and Tuesday, a light day on Wednesday and a light day on Thursday, although on each day she was out for about 20 minutes with a mixture of running and heeling exercise.

Usually she has free run of the house in the evenings, but on two evenings we are out and she is shut in their bed area.

Answer: Elizabeth- Azoturia is the term I think you are looking for. I don't actually know hat azoturia is, though. I have to admit that up front because I don't have any of my reference books that might possibly define it at home with me. But I do think that I can give you a list of possible problems for what might be wrong with your Labrador retriever, so I'm hoping that will make up for not knowing how to define azoturia.

Labrador retrievers have a condition that is known as exertional hyperthermia (sometimes exertional myopathy), that occurs most commonly in Labs, although it is seen in other breeds. If this is the problem, there should be a high temperature, usually over 106 degrees Fahrenheit, during the exercise period that precedes the clinical signs. Affected dogs get weak in the rear legs, may have stiffness and difficulty walking, may seizure and may have myoglobinuria, which is the presence of myoglobin in the urine. Myoglobin is red, so the urine is said to have a "port wine" appearance when myoglobin is present. There is an odd thing about this condition. Dogs that are affected by it are often only affected when they are engaging in a specific form of exercise. A dog may be able to hunt all day but then gets exertional hyperthermia as soon as a Frisbee is thrown a few times for it -- or any other specific exercise that affects that particular dog. Sometimes this problem can be avoided by figuring out what the inducing exercise is and avoiding it. There is some disagreement about how to treat this. Fluid therapy and administration of oxygen seem to be consistent recommendations. Anti-inflammatory medications are frequently recommended. Cortisones are recommended less commonly. Muscle relaxants seem to be out of favor at present. I am not sure what the current thinking is about glucose administration but your vet is likely to know something about this that I don't. Most Labs recover with or without treatment but seem to feel better much faster with treatment. The condition will recur if the inducing exercise is engaged in again. Finding out if there is a high temperature that triggers this is a big diagnostic clue.

There is a condition in Labs known as Type II muscle fiber deficiency. It is supposed to show up in young Labs, so the fact that Tilly is over four years of age seems to make this a little less likely, unless you have noticed that she has an abnormal gait but it didn't seem like a major problem until now. Labs with this condition get weak when they exercise and if they continue to exercise they will get stiff and the back legs develop a "bunny hopping" gait. This is a lifelong problem.

Anaphylactic shock, which can occur with insect bites or a reaction to vaccinations or medications can cause most of the symptoms you are seeing, too. Unless there is a reason to suspect this, it is also an unlikely cause of Tilly's problems. However, if she was vaccinated in the last few days or if she is on antibiotics or other medications, it is something to consider.

There is a condition, exertional rhabdomyolysis, that has been reported in some very athletic dogs. It is a life threatening condition brought on by very heavy exercise. This is a condition that can be induced in any species, I think --- Discover magazine had an article about people getting this after extreme exercise contests (like who can do the most squats in a row). It is a rapid breakdown of the muscle tissue and it does lead to kidney damage and can lead to disseminated intravascular coagulation. Extremely aggressive therapy is sometimes necessary to reverse this condition. This doesn't seem to fit the case history but has to be considered, too. I think that this is the condition that occurs in greyhounds. It also occurs in sled dogs.

Sometimes we see signs like this when dogs have hip dysplasia. They get sore and just don't want to move around much. This tends to show up as dogs age. It often seems to come on suddenly, even though the damage has been accumulating for years. In this case, it is the pain that interferes with activity and response to anti-inflammatory analgesic medications is usually very good at first.

Disc problems and lumbosacral instability are also conceivable problems. These problems can cause pain or weakness or both. There is usually a good response to anti-inflammatory medications at first with these problems, too. If weakness is the major feature of the clinical signs there is likely to be some nerve damage and medications have a less obvious effect in that case.

Once in a while we see a dog that develops cranial cruciate ligament instability in both stifles at the same time. These dogs are often very weak in the rear legs and move with such difficulty that they can easily be mistaken for dogs with disc injuries or myopathies.

These are the things that I can think of. I'd tend to think that the exertional hyperthermia or hip dysplasia/arthritis type problems are the most likely problems, just based on the history. Over time, it will be easy to distinguish between these, if one of them is present.

If the exertional hyperthermia problem does seem likely, I think that Dr. Shelton at the University of California at Davis has developed a test for the condition. Your vet could contact her lab for details on how to submit samples.

Hope this helps some.

Mike Richards, DVM 9/24/2000

Exertional rhabdomyolysis, exertional hyperthermia, and azoturia

Question: It helps a lot. Thank you very much for replying so promptly.

You were the first person (after our vet here) who we contacted and we did some other research on the Internet, particularly in the horse area. We found a load of horse information on Azoturia, and also a very interesting site about a grayhound.

Azoturia, it turns out, is another name for exertional rhabdomyolysis and there is an excellent article about the problem in a greyhound at http://www.abap.org/azoturia.htm.

The article indicates there are three different types of extertional rhabdomyolysis and I wondered if the third type (which fits Tilly best) would also go under the name of exertional hyperthermia? They seem very similar.

We saw from our research that it can be brought on by low levels of sodium and potassium. Tilly has been on a low sodium diet for some time owing to urinary incontinence problems (she is spayed). Our vet also thought she might have some crystals in the bladder, hence the low sodium. She is also extremely fit, and apart from her work as a trialling retriever, she also has plenty of free running exercise and can frequently be off running for quarter of an hour or so (probably longer than a grayhound would run in a race!)

The exertional hyperthermia is an interesting one though. She didn't have a temperature on arrival at the vet, but she did lie down while waiting for another dog being trained while we were out on our walk. She normally sits. We didn't think too much of it at the time. Would her temperature have gone down 6 hours afterwards (when we took her to the vet) do you think?

The Anaphylactic shock is a possibility. She was vaccinated on Monday morning (3 days before this episode). She has had AS before, when stung by a bee at 10 weeks old. Is there any more information on that?

We think that hip dysplasia is very unlikely since she has a 4/4 hip score so we will concentrate on the three above.

Is it possible that the muscle problem (be it exertional hyperthermia or exertional rhabdomyolysis) and the urinary incontinence might be related?

Regarding future avoidance - we have put her back on a normal salt diet (chicken and vegetable nuggets) and we're going this morning to get a blood test for her. Is there anything else we can do?

Having said all this, Tilly is a lot better this morning (Friday). She is still having her electrolytes and we are going to do the massage again today a few times.

Answer: Elizabeth-

I looked at the article that you included the link to. I think that the disorder seen in Labradors is actually different from what is described, but it is hard to be sure of this since few vets get to see a whole lot of these cases.

There are three important clinical signs that it is going to be necessary to look for, if a future episode occurs.

The first is temperature at the time clinical signs appear. Any normal rectal thermometer will work for taking a dog's temperature. The hyperthermia in Labs is reported to be transient but consistent. So the high temperature should occur but is likely to disappear by the time the patient gets to the veterinarian's office.

The second sign is myoglobin in the urine, which produces the reddish discoloration seen. This is a sign of rhabdomyolysis and it should be present if this condition is the cause of the muscle soreness seen.

The last thing to look for is when the muscle soreness occurs. In rhabdomyolysis the clinical signs usually occur after a delay of several hours from the exercise episode. In exertional hyperthermia the muscle soreness normally occurs at the time of exercise, or very close to the time of exercise.

In re-reading the original note, I am not actually sure if either of these conditions really seems all that likely, based on what you saw.

I think that I misused the term anaphylactic shock in the reply I sent to you, too. While I think that a reaction to medication or vaccination is possible, and that it would be an immune mediated reaction. However, anaphylaxis is an immediate reaction to a toxin, medication or vaccination which usually occurs within minutes of the administration of the offending substance. Muscle weakness, salivation, breathing difficulties, vomiting and hives are all possible signs of this.

What I would have to include in the list of possible problems is a condition that I should have referred to as delayed hypersensitivity syndrome. This is a reaction to a toxin, medication, vaccination, infectious agent or other stress to the immune system. Typically, it occurs at least five days after administration of the substance but can occur in a shorter time on subsequent exposures, according to Kristen Bernard, in the "Handbook of Small Animal Practice" (Morgan). This syndrome can produce a lot of different clinical signs, including joint soreness and muscle pain. I do continue to think that this is a possible problem in Tilley's case. If it has occurred, there will likely be reactions to future vaccinations. I know of no way to be sure that this is what happened, unfortunately. Although if it does happen in the future it will obviously be more likely.

My understanding of exertional rhabdomyolysis electrolyte levels is that the sodium level may be low but that the potassium level is usually high, during an episode of this condition. This is one of the things to consider when planning fluid therapy.

I would be really surprised if the incontinence has a relationship to this problem but can't be certain that it does not.

I think that you are going to need to depend on the advice of your vet, after evaluating the labwork, to advise you on necessary dietary changes. The initial problem may still seem more important after this is all over and can be evaluated in retrospect.

I am glad that Tilley is feeling better. That is a very important sign no matter which of these conditions turns out to be the culprit.

Mike Richards, DVM 9/24/2000

Trembling in rear legs

Question: We have an 18 year old mixed Samoyed female about 50 lbs - looks mostly like Samoyed with maybe a little bit of golden lab and terrier background color

This is a long story because she is a long dog

She came to us from the pound at about 8 months old

She has been spayed - when younger probably as a young puppy before getting to the pound

Two years ago she was found to have reduced thyroid and has been tested and stabilized on Levoxin synthetic at 4.5 mg per day

Her back end seems to be gradually failing - this is the problem

About a year ago she was started on Anapril - this was to help maybe with her going outside for business - she is an inside dog who has always been well mannered and always asked to go out - can't say much good or bad for Anapril - changes if any are subtle - she now has degenerated to regularly hitting the floor solid and liquid - even sometimes when we are right there in front of her - and failing to indicate she needs to go out - almost like she is not connected front to rear - we take her out on her regular schedule and she will go outside but sometimes has accident just as we walk back in the door - changing timing and special trips outside have not fixed things - diet is NutraMax for older dogs and does not seem to be a factor - we have tried variations of diet but same pattern occurs

Bridie is still her normal joyful self - she is not gahgah or losing mental function or general interest - again can't say Anapril good or bad - same before and after

She has always carried her bushy white plumed tail high over her back

About 8 months ago she gradually stopped doing this and now keeps it low between her legs except when she is really happy when a few wags occur

Increasingly she has shown unsteadiness on her back legs especially after just getting up - she will occasionally stumble or lurch to the side in the rear when walking - this is the problem we are really worried about

She has been on Joint Care condroitin / glucosamine for 2 years just as a preventive measure

Tried Rimydil about a year ago starting when needed and then on a regular dose ( idea was that maybe she wasn't going outside because it hurt to walk ) - seemed to help comfort wise when running in the back yard etc but not with the messing - but high liver blood test numbers 2 months ago had our vet saying we should go immediately to a liver specialist for ultrasound and should be prepared for the worst - we fixed this problem by just stopping the Rimidyl after reading on the net that some people had dogs dying of liver related Rimydil toxicity - her liver numbers 1 week after stopping are back in normal or high normal ranges and stabilized

Arthritis range of motion testing has been and continues to show good, with and without Rimidyl - no protest or apparent pain when moving her legs as per a much younger dog - now we have Etogesic but have not had a chance to try it out - we are a bit afraid of the liver connection - we do give her buffered aspirin when she acts like she is sore - but this is not often

Muscle mass on back legs and over her rear end seems to be diminishing (visual impression to us who are watching her closely) but her weight remains overall normal - skinny rear end - front normal - both rear legs have same apparent problem, neither is favored

Some trembling in rear legs - rapid buzzing of muscles - will come and go - gets better after walking

Just had X-rays of spine suspecting some type of degeneration - vet came back amazed - spine looks great, like young dog - no disk bulges - vertebrae spacing even - no spurs or missing spots in the bone - hip joints normal with maybe slightly small femur heads but no degenerative changes can be seen - no evidence of tumor or cancer showing

Slightly tight abdomen - some gas - so vet says maybe Cushing's - but vet says Anapril is typical treatment for Cushings - can you get negative Cushings from too much Anapril?

Vet says rectal exam feels normal and organs seem to feel about right except for the abdominal tightness - she did a reflex test where the back paw was turned under - regular dog should immediately turn back up when released - Bridie just left it there three out of four times

Urine test normal density, no infection (she has had a few bouts of urinary infection in the past)

Hair growth has almost stopped - she is getting bald patches and the tip of her tail is now bald

Also, with just a little bit of cold she starts chattering her teeth - very fast again like a buzz - she is off Anapril for the last week - and the buzz seems better - can Anapril cause too much nerve activation? Can rear end degeneration be caused or aggravated by Anapril?

Vet has recommended Cholodin for trial - just see if it does any good

We are now looking at doing an ACTH stimulation test

If this is Cushings and Anapril doesn't affect it what then?

We are worried about her comfort and about losing her rear legs more than anything else - we can always clean the mess

Since we will be going in for more blood tests soon - what else beside the regular stuff should we look at? Any leads to try? I have read your online info - didn't see anything that was a really close fit to these symptoms though

Thanks for the interesting news letter and we appreciate your service - its been a big help

Answer: Turq-

The symptoms of the more recent problems with the rear legs sound like a neurologic disorder. The most likely diagnoses are degenerative myelopathy, a spinal tumor or a herniated disc in the spine. There are other possible problems.

The best approach to a diagnosis is probably to have a neurologist examine Bridie and to have an MRI done of her spine, if possible. In many areas of the country this is hard to arrange. An alternative is a myelogram, in which dye is injected into the area around the spinal cord to outline any areas of pressure on it. This is a good test but not nearly as good as an MRI, based on recent reporting of a high percentage of disc problems in dogs undergoing MRI exams who were previously suspected of having degenerative myelopathy based on a inability to see the disc problem on normal X-rays and with myelograms.

Anipryl (Rx) is not likely to cause Addison's disease (I know of no reports at all of this and it doesn't seem likely with the way that Anipryl is supposed to work). Some vets use if for the "old age shaking" syndrome seen in older dogs. We have tried this with one patient, for a month, but it didn't help in that time. It didn't hurt, either, though.

4.5 mg of levothyroxine would be a really large dosage. I am hoping that you mean 0.45mg. The current thinking is that even big dogs do not need more than 1mg of levothyroxine per day very often. If you are really using that high a dose, I would have to be suspicious that the levothyroxine could be a problem.

The most sensitive test for naturally occurring Cushing's disease (hyperadrenocorticism, HAC) is a low dose dexamethasone suppression test. However, an ACTH response test is still a reasonable choice. The hair loss is a common sign of HAC and some dogs do seem to get sensitive about the cold with this condition.

It would be worth rechecking the T4 levels, even if you are using 0.45 mg of thyroxine rather than 4.5 mg --- but if you are using 4.5mg, it is really important to check the T4 level to see if it is elevated.

I know that proposing even more testing doesn't sound inviting, but if there is a neurolgist or internal medicine specialist with an interest in neurology near your area, it could really be worthwhile to get a second opinion on Bridie's condition from a specialist.

Mike Richards, DVM 4/15/2000

Hind leg weakness in Maltese

Question: We have a one year old Maltese.He suddenly experienced weakness in hind legs,difficulty raising himself on these and is extremely fatigued.Vet suspected lyme and prescribed tetracycline but western lyme test came back negative,Vet then suspected joint problems and gave anti inflamatories.No improvement.Exrays done showed no joint problems.Dog placed back on tetracycline and more general blood screening done for tick borne diseases.waiting for results.Dog does not want to walk,can't jump on or off couch.Some slight improvement so far although todaystanding with right hind leg held off floor.At one point dog was struggling to walk down hall facing forward with hind quarters angled off to the right and slighthly forward..Any ideas? Regards, J.

Answer: J.

I am not going to be able to help much with this one, I'm afraid.

I would worry about spinal disc problems even in a dog this young. If this has not been considered, it may be worth checking into. Most of the time there are neurologic signs but some dogs only have pain, weakness or lameness. Radiographs are often helpful and they would also help rule out other problems, like Legg/Calve/Perthes disease (affects the hips, usually).

I think that Maltese dogs are more prone to portosystemic shunts than other breeds and fatigue or weakness is sometimes associated with these, but things like siezures, "spacing out", incoordination after eating and other signs related to central nervous system irritation are usually evident with this.

If luxating patellas are present, which is pretty likely in a small breed dog, they will sometimes cause significant weakness in the rear limbs. This would be something else to think about.

Lyme or other tick borne diseases are possible and it is good to rule them out.

It is likely to take more than one visit and possibly even a referral to a specialist, in order to get to the bottom of a severe weakness or lameness in a dog of this age. Keep working with your vet to resolve this. If a significant change for the worse occurs make sure that your vet re-examines your dog within 24 hours of the change at the latest --- and sooner is much better.

Hopefully this is improving instead of getting worse, though.

Mike Richards, DVM 10/15/99

Weakness in rear legs

Q: My pomeranian-chihauhau is 12 years old. She wobbles and sways when she walks and her rear hangs low to the ground. A specialist diagnosed her as having a brain-related problem about 2 years ago (i.e. tumor). Some of her health problems that could be related are: disc degneration (she takes prednisone every other day), complete blindness, and diabetes. If taken off of the prednisone, it gets to the point where she cannot walk at all. She can still move fairly quickly, however, it seems that recently her rear hangs lower and her hind legs are pointed outwards. Do you know what this could mean or would any other information be helpful?

A: Weakness in the rear legs can occur with injury to the spine or with central nervous system problems if they affect the areas that control the rear legs. Diabetes can lead to diabetic neuropathy, an inflammation of the nerves that can also lead to weakness in the rear legs. In addition, prednisone can cause muscular weakness as a side effect. It would be hard to tell you which was the problem currently without doing an exam and it may be hard to tell even with a good physical exam and lab testing since there are so many concurrent problems. Your best bet may be to consider returning to the specialist for a recheck.

Sorry I can't help much with this problem. Mike Richards, DVM

Osteoarthritis and nerve damage

Q: I have a 13 year old golden retriever/collie mix...weight 110 lbs. He has been diagnosed with osteoarthritis in back right hip which, as expected, is getting worse. He has been on numerous drugs to help with the pain and stiffness and most recently is taking Rimadyl along with dexazone (cortisone). He had been doing fairly well but going up steps was becoming a problem (fortunately, I have a ranch style home) so I had a ramp built to get from the outside into the house after walks. But on Jan 1, he took a fall and since that time, he is severly lame. Some days are better than others but most days he needs assistance lifting his back legs up and then he needs support under him to walk (I use a towel supporting his belly and help him walk). However, the lack of mobility has caused the muscle in his right hind leg to atrophy. When he walks, his paw is bent over in half (ie., his "toes" are bent underneath the foot) and sometimes he drags his one hind leg. My vet has said that when the weather changes, this situation should improve. He has suggested that I do range of motion exercises and messages to his leg/hip which I am doing. Obviously, I love my dog, Brandy, very much and I want to make sure that I am doing everything possible to help him. His appetite is still good (on a prescription diet food to help reduce his weight); he is alert and attentive; he does not seem depressed. Your comments and suggestions will be much appreciated.

A: The "knuckling" of the one rear leg can be a sign of nerve damage, which would be a little different than the arthritic condition previously being treated. The nerve damage could be to the sciatic nerve or possibly to the nerve roots coming from the spine. If this is the case, recovery may occur but it becomes less likely the longer the signs remain. It is sometimes very hard to tell if nerve damage is present when there is chronic degenerative joint disease since the atrophy and sometimes even the posture can also occur over time from that problem as well. There is not much else you can do if nerve damage is present, unfortunately. Some people believe that Vitamin E is beneficial in doses up to 2000 IU/day for degenerative neurologic conditions of older dogs. It is not too likely to be harmful, so we do try it pretty often. I have to admit that I really don't know if it ever helps, but sometimes it seems to. This is also a time we consider use of the "nutriceuticals" -- food products like Arthroflex (Rx) or Cosequin (Rx) which may be beneficial in chronic debilitating conditions. Weight loss might help your dog. Keeping an arthritic dog thin is one of the best things you can do to alleviate the clinical signs of arthritis but it is also a very hard thing to do, especially in a dog in which you can not encourage more exercise and are using corticosteroid medications. If it is possible, it could be beneficial. I wish I had better suggestions for you.

Mike Richards, DVM