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Is This a Good Idea?

  1. Dec 20, 2009 #1
    Imagine a device that allows athletes with knee injuries (or anyone for that matter) to be able to walk, run, jump or play any type of sport without ever putting pressure on the knee. I would like to know what you think.
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  3. Dec 20, 2009 #2
    Well, the force would have to go somewhere and who knows what problems might arise from that. Since the knee is already designed to handle the what it goes through, it doesn't seem useful.
  4. Dec 20, 2009 #3
    Based on what some in this forum have said before, you'd just be taking concepts that already exist and putting them together in a unique way (knee injuries and device are found separately in books). Those individuals from the forum would say "Not from a book". However, a reasonable and prudent person would say it shouldn't matter and all ideas come from combining ideas which already exist.

    The idea sounds impractical and not something easily created, but if it helps some with bad knee injuries while they're recovering, it'd be useful.
  5. Dec 20, 2009 #4
    What about the same idea but for the ankle? I think it might be more practical.
  6. Dec 20, 2009 #5
    What are some ideas of how you may do it?
  7. Dec 21, 2009 #6
    I don't know how it might be done, but I want to know if it was done whether or not it would be used. For example, if a soccer player was to sprain their ankle and used this device, can they play with the sprained ankle?
  8. Dec 21, 2009 #7


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    Depending on how the device is arranged, relieving force/pressure from ankle or knee would cause an increase somewhere else. Ostensibly the device has some mass, so more force would apply to the foot perhaps, unless one is thinking of replacing the entire leg with some exoskeleton system, in which case the hip might have to deal with more stress.

    Anyway, I believe such devices already exist for those who are paralyzed from the waist down.

    For knees and ankles, there are bands/braces that one can wear for support, but circulation can be an issue.
  9. Dec 21, 2009 #8
    Yes. You should check out some of the stuff the Honda has come up with over the years of developing Osimo. They have a lot of great stuff for those with trouble walking or climbing stairs; most of an exo-skeletal nature.
  10. Dec 21, 2009 #9
    Astronuc, if what you say is true than the honda walking assist wouldn't help because it's putting pressure elswhere.
  11. Dec 21, 2009 #10
    If it were possible, it is unlikely that the player would be able to compete at the same level he was before the injury.
  12. Dec 21, 2009 #11


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    More pressure on the behind - as is the case with a wheel chair, which basically replaces the function of the legs.

    Looks like Honda has a product - but for folks with weak muscles.

    Perhaps it could be extended (even to artifial feet) to protect joints.
    Last edited: Dec 21, 2009
  13. Dec 21, 2009 #12


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    Yes, relieving pressure from the ankle or knee increases the pressure on the ace bandage (or the brace for more sophisticated devices).

    They do provide "help" when the person has a minor injury or is recovering from an injury. They lessen the pressure on the body part, but they don't eliminate all pressure and strain.

    I actually think you might be right about a device that took all pressure and strain off an injured body part. In order to do that, it seems like there would have to be a constant low level stress applied to the point where the brace integrates itself in place of the body part. But the other body parts aren't experiencing any more of the forces from movement than they naturally would.

    But, even an Ace bandage can be a huge help to players with injuries. The support probably comes with a cost, since there's more resistance to bending the knee, for example, but it's a lot better than having a knee that just feels "sloppy" and isn't responding well. Of course, since an Ace bandage is only reducing strain instead of eliminating the strain, the injured body part might be taking enough strain that the injury gets worse. From personal experience, by the fourth straight night of relying on an Ace bandage, the results just aren't that great. I got four more games in spite of an injury, but couldn't play for two months after that week (but, the extra games I played in were playoff games at the end of the season and the games I missed during those two months were pick-up games).
    Last edited: Dec 21, 2009
  14. Dec 21, 2009 #13
    Can the pressure taken off be applied not to a body part but to a mechanical device? But i do like the idea of taking pressure off an injured body part and putting it on a stronger part of the body. Isn't that how a seat belt works. If applies force to a more durable part of the body instead of a more vulnerable part such as the head?
  15. Dec 21, 2009 #14


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    No. The pressure/force will be applied on the parts of the body in contact with the device. It may be possible to redistribute force/pressure to a larger area.

    Seat belts are restraints to prevent a body from slamming into the steering wheel, dashboard or window in the event of a rapid deceleration of the vehicle, or the door in the case of lateral acceleration. The seat provides support for driver and passengers, and the seal belt applies only in the event of an accident or emergency maneuver (e.g., rapid breaking).
  16. Dec 21, 2009 #15
    I still don't understand this.
  17. Dec 21, 2009 #16


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    A mechanical device must be attached somewhere to the human body in order for the body to use it.

    If a device it designed to relieve pressure on the knee (or add support) it must, at a minimum, be attached to the leg above and below the knee, which is what a mechanical knee brace will do. The interface above and below the knee will then bear the load that would otherwise be transferred to the knee.

    One could build an exoskeleton for each leg, or both legs, in which the mechanical interface might be the thigh or lower abdomen/behind. In those cases, the weight of the body is supported at the thigh or lower abdomen/behind, rather than foot, ankle or knee.
  18. Dec 22, 2009 #17
    Oh, okay then
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