This article, written by Derek Levy, an above knee amputee, was published in Coasting Together, the Website of the dynamic Sussex Rehabilitation Centre User Group of the same name, on March 29th, 2015.
We are very grateful to Coasting Together for allowing us to use this excellent and informative article on our own Website.
There appears to be a rapidly growing interest in paracycling. 2 of our Ambassadors are enthusiastic road cyclists both now taking part very successfully in Time Trials and it’s good to be able to publish something from a keen mountain biker. We’re sure you’ll find Derek’s article helpful and inspiring…
“…On yer bike!”
Cycling as an Amputee
by Derek Levy
What are the issues for an above knee amputee that wants to do more than flat towpaths?
I have cycled forever and was an early follower of mountain biking, starting some 25 years ago. After I lost my leg I was frustrated at not being able to do what I did before. I used to participate in an annual boys’ cycling trip typically a 3 day pub crawl over such routes as the Trans-Pennine, South Downs Way etc., with diversions would aim for about 200 miles. The first event after the amputation was a Dutch tour – The Netherlands is flat with lots of cycle paths and I became very optimistic thereafter. Suffolk /Norfolk was hilly (they are meant to be flat); Welsh borders are too hilly, just did the pubs and drove; Thames Valley; my stump was too sore with broken skin. For the Essex tour, I was too unfit and pulled out after a day. 2013 was north to south Devon – a great success! This year Northern Ireland, also a success.
The success of the Devon trip was in a large part due to the fact that I had made changes to the bike which cured all the issues I had cycling post-amputation. What are the issues for an above knee amputee that wants to do more than flat towpaths? The issues I had were:
Getting on and off the bike/starting
When cycling correctly at the bottom of the stroke the foot should be slightly toes-down and the knee will still have a slight bend – it should not be locking out. This requires quite a high saddle height, such that when I initially returned to cycling the only way to get on the bike was to lean against a free car or lamp-post. This has surprising limitations and I found the process quite confidence-sapping. At least two heights are needed. A relatively new invention for serious able-bodied off-road cyclists is the dropper post. This allows for control of the saddle height from the handle bar. For a fast technical down hill, the rider will move their weight back – placing ones bottom over the rear wheel whilst lying over the saddle, and when in a climb the saddle will be fully up. There are two main designs mechanical and hydraulic and as with all such add-ons there is a range of quality, precision and reliability. Being an above knee amputee I struggle to have much fore and aft movement, the huge benefit is being able to ride….normally and get on and off safely without assistance. I do however reduce the saddle height in a bumpy descent to reduce impacts- not being able to stand on the pedals.
Keeping a Prosthetic Foot on a Pedal
With a standard pedal the foot will just fall off the pedal, there being no feedback loop. I used a standard toe-clip and pushed the foot in by hand at the top of the stroke whilst leaning against a free car or lamppost. Awkward. I now use an SPD type clip. This requires a special shoe and pedal that are available at all cycle stores. The sole of the shoe incorporates a male clip that bayonets into a spring cleat on the pedal; the foot is then positively attached. This allows greater security and control. Power transmission is also more efficient. To unclip requires the foot to be rotated by around 20°, I do this by moving my knee in.
A prosthetic knee does not have the same articulation as your natural one; another reason to have a high saddle. I use a Mauch knee when cycling; I like the ease at which it can go into free mode (a couple of weeks back I appreciated being able to lock it when the path turned into a steep and unexpected sand dune for 200+m). It does however have a much smaller bend angle than a natural knee and is happier with a smaller rotation diameter for the pedal. With a standard rotation the knee tends to hit the stop and that in turn tends to make the socket move on the stump. To overcome this problem I have fitted a crank reducer.
Socket Fit on Stump
For me there are two main issues: the security of the socket on the stump and skin abrasion Cycling in hot weather can be problematic when the sweat builds up and the socket can piston down the stump; not good. My socket is held on by suction only and my socket is an unusual shape. I keep my stump hair-free; that helps with minimising wet blisters/abrasions. I use bandages such as Hypafix and Medipore in areas where I know the socket will dig into the skin. Applying a deodorant over the whole stump can also help. My first leg had a belt to keep it in place, it helps a little.
I recently rode with some new able-bodied neighbours, very fit etc. on serious kit (£4k carbon frames etc.) who have raced…I kept up!
Best wishes and bike safe.
You can visit the Coasting Together Website by clicking on the banner at the top of this article.Tags: above-knee amputee, Coasting Together, mountain bike, Time Trials