A walking device trial

One HSPer’s experience

 

Malin Dollinger, Board Member of the SP Foundation in the US, medical doctor and HSPer himself, recently trialled a device to assist people with spinal cord injury to walk.

Malin writes:

Many of you may have heard of / be familiar with a robotic walking device, that was originally created for the military, so soldiers could carry heavy loads, but has lately been adapted to allow paraplegics to walk.  It is controlled by its own internal computer, which is programmed for each individual patient. If you do a Google search for “Ekso” you will find information/ see the video. It is an exoskeleton, that is it fits around the legs and feet, and straps to your chest and abdomen, and weights about 50 pounds.  When fitted and working properly, the machine recognizes from your body movement/ leaning/ posture what you want it to do, and will stand you up from a sitting position, and will tell your legs to move in a walking mode, with your continuous instructions by body posture and leaning, to enable you to walk.  The device bears its own weight, so you don’t need to lift anything. There have been some amazing and important successes with paraplegics, in particular with spinal cord injuries.

Ekso exoskeleton

That being said, this device looked so interesting, important, and practical, not to mention useful, that I began a correspondence with the company in Northern California with the aim of trying out the device.  It is currently not being sold commercially, but remains in clinical trial. A few weeks ago I spent an hour with a designated physiatrist [physical medicine physician], to see if I would qualify for a formal trial.  He took many measurements of range of motion and strength [everywhere!], and I was subsequently accepted for the trial.

I was greeted by a team of six physical therapists, including one from the Ekso company, who spent an hour making even more complete and elaborate measurements of my strength and range of motion, my legs in particular. There were some limitations of range of motion of my right lower leg. The device wrapped around my legs, needed to have many adjustments made to fit my body, and had knee pads, foot plates, abdominal binder, shoulder straps, and various other fastening devices, all tailored to me. Once the apparatus and my body were “assembled,” there was no voluntary movement possible unless the on-board computer was told to do so, either by the therapist or by me, via leaning/shifting weight/etc. They placed a large heavy-duty walker around me, to hold onto.  After much time was spent making adjustments, it was time for me to stand up. They told me what to do, and what not to do, and in phase #1 they control the computer. The told the device to “stand up!” and so it did, with me inside. Then, in the standing position, they made more measurements of range of motion of my lower legs.  It seems that the initial evaluation showed that I lacked about 7 degrees of [backward] knee flexion in the right leg, thus when you walk, you put one forward while the other is “behind” you, then you take the behind foot and put that forward, etc. The 7 degree flexion lacking was slightly less when I was “inside” the device, but this became a major problem. If I could not tell the machine to “walk,” not having sufficient flexion in both legs to correspond to my taking successive steps, the machine’s computer could not be programmed to recognize that the back foot now needed to step forward and become the front foot, etc. This is somewhat analogous to “training” the WalkAide device, a little box worn below the knee, that tells the lower leg muscle to lift the foot up [prevent foot drop] whenever you start to take a step. By comparison, the WalkAide is immensely simpler; you’re moving only one muscle to make the toes go up, alternately.  The Ekso is extremely complex, moving your ankles, your knees, your hips, and your entire body, and it knows when your torso/chest is upright and aligned. It keeps track of the angle of every one of those areas/joints, and responds appropriately.

At that moment, I realized, and they confirmed, that because of the slight limitation of the range of motion of my lower legs, I would not be able to use the device, since I could not make its computer understand and respond to my too-limited motions. I give them great credit and appreciation for their time, energy, and expertise. They were kind, courteous, and always reminded me that they were there to help me and to protect me from any injury [what happens if I fall in this contraption during the test] ..not possible: the whole thing is fastened to a steel track overhead, like a rock climber or a gymnast or diver practicing, so if I would start to tip, it would catch me.

Conclusions:  I’ve had HSP for some 20 years, which is enough time for scarring in the muscles to occur, with limitation of the range of motion. This is the telling reason why this did not work for me. And this seconds the common admonition about getting regular physical therapy that keeps your muscles “loose” and non-contracted. So people need to try this device much earlier, before chronic contractures and limited range of motion occur. Of course no one was thinking of HSP or PLS when this was invented; spinal cord injury was the rationale. Spinal cord injury has the attribute that the date/ moment of the injury/ beginning of paraplegia is precisely known, and once the healing has occurred from the injury, there could be a trial of this device at a time when it could do the most good, before scarring and contractures.
Related article
http://www.nytimes.com/2012/09/12/technology/wearable-robots-that-can-help-people-walk-again.html?_r=0

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