Physical Fitness and Safety with Mobility Service Dogs

The job description of a mobility dog can include a myriad of things. Wheelchair pulling, button pushing, flipping light switches, counter balance, bracing, item retrieval, door opening and closing and momentum pulling, just to name a few. Whatever mobility tasks a service dog is trained to do are things they should be more than physically competent to perform.

For example: an 8 lb Papillon can do light item retrieval (keys, medicine) and may be able to operate a K9 phone, certain adapted light switches, open lower, lightweight doors, but they are in no way capable of pulling a wheelchair.

Another example: a 58 lb Chesapeake Bay Retriever (I'm using Saxon in this example!) can easily tug doors, turn on/off lights, press handicapped buttons, counterbalance, item retrieval and momentum pull, but is NOT capable of bracing. I will never ask her to learn to square up or stiffen her body for bracing. She will never be large enough to support the weight I carry.

Yet another example: a 90 lb Doberman can easily do most if not all mobility tasks that could be required, including bracing. A 90 lb dog will be large enough for most adults who are of average or overweight (NOT obese) size to do brace work with.

For this post I'm not mentioning program trained mobility dogs because they generally come with their own set of trained tasks, health check up, mobility harness/gear with usage instructions and have been chosen specifically for the client. The following questions are geared at those people who have mobility issues, either diagnosed or self assessed (symptoms can still impede your overall mobility) and decide to train a mobility dog for themselves.

What mobility tasks can you not live without?

First you need to have an honest discussion with yourself and anyone who knows you and your issues well (family member, friend, doctor) and can provide insight into tasks you may need. Come up with symptoms or scenarios that make a situation challenging or limit your mobility. Then assign tasks to those things you struggle with and rank them from most important to least. Make sure to distinguish between tasks you do not think you could function well or at all without, and those that would make your life easier. (get medication when you cannot get up to get it yourself vs. turn off your light at night when you're capable, but comfy in bed).

Is the dog large enough to be able to perform all the tasks you need ESPECIALLY if you want them to bare weight?

If you have a specific breed of dog in mind you should be comparing the average height and weight of that breed to what you are hoping to have the dog someday perform as tasks. There are a lot of weight ratios thrown around. I've heard the dog is supposed to be 50% of your weight and 40% of your height (measured from their shoulder) to be deemed large enough for heavy mobility such as bracing. It's 30% weight and 30% height for counterbalance and momentum pull I think. I'm not sure where these numbers came from or if they are just arbitrary percentages. I think for bracing 50/40% is accurate. Counterbalance and momentum pull I personally disagree with as I've seen videos of Chihuahuas pulling 500+ lbs in Weight Pull. In the right harness (not on a flat collar, prong collar, head collar or front clip harness) there should be absolutely no issues with straight momentum pull. But back to the bracing percentages. If you weigh 150 lbs and are 5'6, your dog needs to weigh 75 lbs minimum and be at least 26.5" at the shoulder. If you weigh 100 lbs I still think dogs should be minimum 60 lbs, but that's my personal feelings. Most dogs under 60 lbs don't have the bone build to support significant excess weight, even if only momentarily.

And in every single case where the dog will have any weight applied it is essential to your dog's health that you get the dog's hips and elbows x-rayed and then looked at by an orthopedic vet to determine joint health. Failure to do so could cause unnecessary pain and additional issues in a dysplastic dog. Although it is possible to get with a dog with great hips, either all but guaranteed by hip scores in the dog's lineage, or purely by luck. In any case though, a dog you are asking to physically support your weight for your health should not have their health left up to luck and chance. A dysplastic dog does not need to be supporting their handler's weight if they are struggling or could at any point begin to struggle to support their own. The dog should be 2 years prior to final x-rays that will determine the mature hips and joint structures of the dog. 2 years is generally when the joint capsules have closed, though in some giant breed dogs it may take up to 3 years for all joints to close and bones to have fused. It can seriously harm a puppy or young dog, even a large or giant breed, to brace on their unfused joints.

In the 2 week old pup there are clear spaces in the joint capsule of nothing. You can see how far the bones have to grow to be able to touch each other and create strong joints. The 7 month old has most of the bone structure but the bones are still softer as they have not are not fully hardened to how they will be as adults. The last photo is an x-ray of a dog with a healthy set of adult hips with hardened bones and complete joint sockets where the bones fit well together.

There are many mobility harness makers, several of them making custom harnesses to the dog's specifications. Unless you can go to the harness maker's store front to have your dog measured personally, the handler is often left to get their dog's own measurements. A proper rigid bracing harness consists of a a piece of metal that runs horizontally across the shoulders NOT vertically up the spine. The strongest point on dog to bare weight is right across the shoulders. When bracing on the shoulders it is imperative the dog be taught to square up and brace to minimize likelihood of injury for both dog and handler.

Prior to putting on any rigid handled harness, the dog must have already mastered squaring up and tensing up muscles prior. Training a mobility dog, contrary to some things I've seen floating around, is not as simple as throwing a harness over their head, buckling it up and just walking with it. The dog does not automatically know what to simply because they are now wearing a mobility harness. What I mean by this is the dog stands with both of their front feet together so the shoulders line up. The back feet are in line with the shoulders and are also square (not one significantly forward or backward). From this position the dog has the best ability to brace themselves effectively. I am using the word "Brace", but whatever you call it ("Stiff" "Hold" "Steady") the behavior is the same. The dog who has now mastered squaring their body will now need to learn how to stiffen their muscles in response to pressure being applied. This is NOT a behavior that can be introduced, learned and proofed in a single training session. This behavior also should NEVER be taught with a mobility harness. The harness should be added later once the brace behavior is solid.

Handle height is important. The proper way to measure for handle height is for you to up as straight as you can with your arms hanging loose at your side. Whichever side your dog heels on, make a loose fist with that hand. That is the height your mobility handle needs to be. Your shoulder should not raise to extend your arm nor should you be able to bend your elbow while holding the handle. When measuring for a handle you will stand as straight as you can, let your arm hang and hold it as if you are gripping a bar. It may actually help to hold a pen or marker while you are measuring from the distance from your hand to the floor. The other number needed to get a handle height is the dog's height. My dog is 23" at the shoulder. The height from my relaxed arm with a  closed fist to the floor is 30". Therefore I would need a handle height of 7".

It is not advised to do mobility with a dog for which you would require greater than a 6" handle. Although there are harness makers that will add handles of heights as high as 14", that is too high, and a dog can far more easily get harmed with the same action and force with a 10" rigid handle vs a 4" one. When a handle is too high too much pressure (such as a full force brace) or an incorrect brace (where the dog is not squared and the handler may not be completely next to or parallel to the dog and handle) it creates something called torque. Torque for those who aren't mechanics or into physics, is defined as: a twisting force that tends to cause rotation.

Naturally any twisting force repeatedly applied to the spine and shoulders of a dog of any size is as dangerous as it sounds. Since to my knowledge none of the rigid handle harnesses on the market come with a detailed instruction manual including safe, proper usage, the handler/owner of their service dog's new harness must now choose between trying to figure out what to do on their own or rely on the sometimes misguided advice of trainers or the internet. Bracing as carried out ideally will have the handler cue to the dog to stop or the dog auto stops. The handler asks the dog to square up if the dog has not already done so. The handler puts pressure on the handle to lever themselves up, usually from lower to higher ground (curb or stair) or from seated to rising such as standing from a chair. The dog remains still with muscles stiffened while the handler has hands on the handle. This is momentary pressure. The dog's back is not meant to sustain the prolonged pressure of an adult's body weight.

A dog should not be asked to brace while they are standing. The handle may be used for steadying purposes, such as reaching out to hold it or reorient in space, but at that point it is unsafe to apply any weight or downward force as the dog is not squared or prepared to brace. A rigid handle should not be used as a crutch or cane. Even a dog large enough to handle temporary bracing should not be subjected to step by step partial or full adult weight with downward force. If every step needs physical support above steadying simply by way of the handle simply being held, another mobility aid (cane, crutch, walker) may need to be added so the dog's safety can be ensured.

On the note of discussing bracing in motion, a dog cannot square their body in motion, so bracing with a handle of any height cannot and should not be done in motion. The handle is NEVER meant to be pushed forward or backward. It is NOT a guide handle. There are a multitude of other harnesses that have guiding handles or pull straps if that is what is needed. There are also harness makers who combine a mobility harness with a rigid handle with a guide handle or pull strap attached so the harness can serve both functions.

One thing I see frequently in some of the service dog gear groups targeted toward mobility harnesses is that people will buy a rigid handle thinking they need it or that their disability manifests itself far more physically than it actually does. I see a lot of people trying desperately to downgrade their rigid handle for a soft handled balance harness. One of the only real differences between a rigid handle and a non rigid one is that a non rigid handle cannot be used for bracing at all. It can however be pulled up on to help yourself up or to hold the handle while the dog leans the opposite way, providing momentum to help you right yourself. A non rigid can double as a leading harness and can be used for momentum pulling and counter balance.

With one final comment, if you require an 85 lb dog, a dog who would at peak fitness be 70 lbs should not be used because it weighs at or in excess of the necessary 85 lbs. A dog who carries a good deal of excess weight should not be used as a mobility dog. There is simply no selfless way to ask a dog, even a trained dog, to support your weight and many multiple excess pounds of their own. I'm not talking a 3-5 lbs too many. There are so many dogs I've seen who weigh probably 20-30 lbs overweight, and I've seen some who may even be 40+ lbs overweight working as bracing mobility dogs. It's just not fair. After a diet if they are healthy and fit (and evaluated by a vet to be cleared after a large weight loss) sure, but until then, the dog doesn't need to carry more than his own share of weight and yours too.

Just for kicks, here is my little Mochi dog wearing a mobility harness. She is a retired service dog, but she never was a mobility dog.

"Hey Mochi! What are your thoughts on small dogs, unhealthy dogs, other unsuited dogs being used as bracing mobility dogs? I'll make this tougher, contemplate this quandary! What if it's not an issue with the dog, but how the handler uses the harness? Mochi, think about this, what if it's both?"

That above is Mochi's response. She says USE COMMON SENSE! I concur. Wisely spoken, Little One, wisely spoken.