There is so much to write about, that this is becoming a daily blog again. I'm sure that won't last for long.
I woke up at 8 after a good night sleep. (drug assisted).
I decided to make the day a leg only day. No Wheelchair.
The leg went on in record time. It is getting easier every time. There is still the problem of it not going in far enough, but it will settle as the day goes on, and the leg will get shorter.
Last night my Texas buddy and I were chatting about how the brain never really knows where the prosthetic leg is. Like when you get out of a chair and find your leg is numb and asleep. There is no feeling, and no feedback of what it is doing. So you sit down and massage it till the feeling comes back. I live with that "no feeling" every day.
All the modern prosthesis, whether mechanical like mine, or computerized bionic ones, all leave the human brain out of the loop. I never KNOW positively what is happening. I simply eventually build up trust that the leg will be, where it should be. The position of the leg is always a probability. We strive for 100%, but it never will be.
I used to walk about 10,000 steps a day. If the leg is 99.99% always in the correct position, that still means I will fall once every day. That falling will probably be at the worst time, when something important distracts me. (Like a coming train, or an attacking dog)
A fall a day means, an injury a day.
I found online about some guys that are working on this exact problem. They are trying to incorporate some means of telling the brain what is happening.
http://www.amazon.com/Neuro-Robotics-Interfaces-Rehabilitation-Augmentation-Performance-ebook/dp/B00S16PTL0
They are wanting the prosthesis to be a robot controlled by the human brain.
One thing I found interesting in the excerpt from this book, was that they used many force sensors to measure everything on a prosthetic leg. One thing they measured was the force applied by the human muscle to push the stump downward when rising from sitting.
They found that more force was applied when using a power servo assisted knee than with a non assisted knee. The more assistance in getting up, the more force from the human. Exactly backwards from the way you would think.
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11:30
Whew. I just walked to the big gate down the street like I did when learning the crutches. Only a few hundred meters, but it is a start. I can walk much faster than I can crutch. When going fast, I can feel the leg snap straight better. I was keeping the good leg, and prosthesis leg length of stride the same. This knee does that kind of walking well.
As usual I used the two crutches, but the left one never touches the ground. It is for fall stopping only.
The knee doesn't do busy standing well. While cooking my breakfast it collapsed twice, but I stand with the leg almost against the cabinet, so the knee hits the cabinet, and stops, and that also warns me.
I need a warning buzzer when the leg is not locked, and weight is on the heel. The only time this condition exists, is when sitting down, or falling down.
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13:00
I decided to play with the adjustment on the leg. I want to make it have more resistance when collapsing to give me more time to catch myself. I call it stumble recovery. The official manual calls it "Stance phase resistance to knee flexion when the prosthesis is loaded." I guess that would be "sprtkfwtpil" for short.
The sprtkfwtpil adjustment is a tiny Allen screw that is hidden, and hard to reach. Not like the swing phase adjustment that are big easy knobs.
I get a mirror, and have to bend way over to reach, and see the back of the knee. I struggle to get the Allen head wrench in the sprtkfwtpil hole while upside down using a mirror. The mirror makes the upside down, upside up but backwards, so everything is upside up, except my head. Now...I have to turn the screw which way?
I take my leg off, and put it on my lap.
I find that the screw is all the way at maximum resistance already. I wish it could go much farther.
Oh well...That was a total waste of a half an hour.
I put the leg back on, but it is a bit skew, so when I stand I look like a duck (well half a duck).
I take it off and try again. Now I am pigeon toed.
I try again, and third time I am lucky.
I wasn't quite as skewed as this guy.
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17:00
I have walked to the gate twice more. That's 600 meters for the day. On the second trip I tripped. :-) But that crutch held just off the ground at the 10 O'clock position saved me. It hit the ground hard at exactly the right angle. My legs were way back behind me. I don't know what happened. I think I didn't push on the toe with enough force, and it thought I was still in stance mode, and starting to sit, so the hydraulics were tight to lower me into a chair slowly, and what I wanted was zero hydraulics to swing the leg forward.
A simple thing like that means a bad fall. Without that crutch, I probably would have been hurt bad. There is nothing to break your fall except the one hand. That is why there are so many broken wrists from leg prosthesis.
Usually when a two legged person trips, a knee is first to hit the ground. But with a prosthetic, the good leg is behind you with the bad leg. Both feet are together behind you as you fall. Similar to being tackled in football or rugby.
That old man at the pharmacy had it right. If I make a 3 page list of the important things to do when walking on a prosthesis. Top of the list is "DON'T FALL". Now got to page three and you will see the things that Bradley talks about.
"Keep the strides the same between prosthetic and the good leg" That is on page 3.
"Keep your hips forward so the hip flexors can be used to put pressure on the toe." That is on page 3.
Everything listed on page one and page two is "DON'T FALL!"
That old man, when he got to work, he locked the knee straight. On a R230,000 bionic knee, and his first and only thought was "DON'T FALL!".
Maybe a young athletic person can handle a fall, and the injury that goes with it. But for an old man with cancer, an injury can last for the rest of their life.
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