Prosthetic Leg Connector

Votes: 0
Views: 12921

This is a device to aid those who wear prosthetic limbs. The current state of the art is a multilayer system that consists of a cotton sock and a silicone rubber sock that fits over the limb. The prosthesis can attach to the silicone sock by means of a rod and ratchet device. In the case of an artificial leg the user places the rod into a receptacle in the leg and steps into it. The ratchet then holds onto the rod. However this can cause problems for patients who are physically weak or who suffer from tenderness in the remaining upper leg. The stump may be swollen and tender after amputation. That is enough to stop the patient from trying to use the prosthesis and perhaps remain wheelchair bound as a result. My dad got MRSA and ended up losing his leg. He ended up with a lower leg prosthesis. It took almost two years before he was able to walk with a cane. This was due to the discomfort and his inability to pull the thick silicone sock or cup over his stump. It took that much time to build up strength and get used to the pain from the silicone sock. This device replaces the silicone sock and allows for much easier “application” and better comfort.

This device consists of a donut shaped chamber on the bottom of a special designed silicon sock which has several vertical expansion chambers. The donut shaped chamber is a reservoir for fluid. When pressure ie from standing is placed on the socket it compresses the donut/toroid which pumps fluid into the vertical expansion chambers which then grips the limb. When the weight is removed the fluid returns to the chamber and the grip loosens as result of the actions of a person walking and putting their weight onto the leg.

This will provide multiple beneficial effects. The most important is the increased comfort level. Second is the massaging action. This will also provide tactile feedback that lets the patient know when he is putting weight on the limb. A new amputee goes through a long course of multiple fittings in order to get the leg to fit right and be able to walk on it. In the early stages there can be changes in size and shape of the stump. An improper fit or discomfort may inhibit the patient’s confidence in using the new limb. As there is no feedback from nerves in the foot it may feel to the patient like his upper leg is balancing on a stick or stepping off into mid air. To get the typical cuff on and keep it on the patient can end up with chaffing on the stump which also inhibits his desire to use the new artificial leg. This device will help eliminate these kinds of problems and enable the amputee to wear it longer from the beginning thus learning to use the artificial limb quicker.

  • Awards

  • 2012 Medical Category Winner
  • 2012 Top 100 Entries


Voting is closed!


  • Name:
    Dave King
  • Type of entry:
  • Profession:
  • Number of times previously entering contest:
  • Dave's favorite design and analysis tools:
    Pencil and paper and solidworks
  • Dave's hobbies and activities:
    private pilot built airplane autocross racing.
  • Dave belongs to these online communities:
  • Dave is inspired by:
    I just watch and look. When inspiration hits all the bits of information begin to fit together. I have watched and listened to the problems people have and want to help. Sometimes that add more incentive than if you just got paid to do the job.
  • Software used for this entry:
    Comsol 3.3 + Solidworks 2009
  • Patent status: