Cycling, suction socket.

[allenuk]

I was being measured for my suction socket yesterday, and noticed that it was v.hard to bend my knee backwards as far as I can with my liner and pinlock system.

Anybody else use a bka suction socket and ride a bike? If so, do you find the lump of liners behind your knee a problem, or will it subside given time?


Allen, bka.

[billf]

Allen: I am making the assumption that the suction system you refer to is an elevated vacuum system that includes a sleeve to complete the vacuum seal. I do not cycle, but invision driving a clutch type truck/auto with a similar system in place. Shifting gears requires flexing the knee to operate the clutch. I could not safely perform that action with a vacuum/sleeve system. I moved on to a 5 ring seal in liner system (suction but no elevated vacuum) that is working out very well for me. My only dislike is when i get down on my knees, I can break the suction, leading to difficulty getting upright without the leg secured.

[allenuk]

Thanks Bill.

Yes, that does describe my new system - unfortunately!

Allen.

[ann58]

'billf' is your system like the one STAN PATTERSON {out of Florida} makes?

[billf]

Ann: I have heard many good things said of Stan Patterson and his vacuum socket fabrication skills, but I live far away from his location and use a local leg man. My arrangement is pretty conventional, using a Ossur 5 ring seal in liner and a socket that is fabricated for the liner. The socket is actually cast while the liner is on the limb. The inside of the socket has a mirror like surface finish to allow the 5 seal in rings to seal to the socket. Some sort of lubricant must be used to don the socket to permit the liner to "slip inside" the socket without damaging the 5 seal rings, which seems to be fabricated from a soft silicon type material that could be torn or damaged easily, preventing the rings from sealing the limb to the socket. BillF

[paralympiccyclist]

I've written a blog post about my cycling leg, which uses a suction system: 637daystogo.blogspot.com/2011/06/winning-is-all-about-your-pace.html

Essentially - a dedicated cycling leg will be cut lower int he back than a walking leg, to allow for more bending at the knees, etc.

Have a look and see if it's a similar system to what you're using...

[allenuk]

Colin: I will have a look at your blog, but my prosthetist and me took the decision to shelve the suction version for the time being and concentrate on trying to improve the pinlock instead. We might go back to suction, but from a lifestyle point of view, pinlock suits me better - and it means that I can stick to just one leg for cycling/walking/generally getting on with, rather than a series of differently modified ones for different activities.

I asked a similar question on the LLIC board, and the suction cyclists there said they all had pinlocks as spares for use as cycling legs! All except Margaret Biggs (another paralympian cyclist) who just uses her ordinary suction leg when cycling, but doesn't roll up the outer sleeve. Which means that when she dismounts, the leg falls off, unless she remembers to grab hold of the top. Extraordinary woman that she is...


Allen.