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-   -   Any BKA's on BF (

Nate552 03-05-10 10:01 AM


Originally Posted by ElJamoquio (Post 10483494)
you guys rule.


botto 03-05-10 12:39 PM


roboleg 09-18-11 11:22 AM

My name is Brent and am a below the knee amputee as of Sept 2010. Oct 2010 i received my first prosthesis and rode 100 feet the first day. Worked through the winter and started riding with a local club May of 2011 and am now up to 100-150 mi/wk.
Completed benefit ride yesterday of 50 miles with average of 18 mph.
I ride 2009 Trek 2.1 and 1982 Motobecane. I use Mtn bike shoes with spd pedals as mtn bike shoes are safer to walk in especially when you can feel one foot.
I started riding for rehab only but have now developed an enjoyment for the sport due largely to the support of riding club. I will always remember the day one on the riders, a rehab Dr., literally pushed me up my first killer hill.:cry:
It's not all about me but what we can do for others as this this good friend demonstrated that morning. By the way he was on a fixie.:)

Juan Foote 09-18-11 01:00 PM

Great to hear Brent. My name is Martin, I have been an LBKA since 07 (in case that wasn't in the first post).

I was wondering, what do you do about your trimline in order to keep from rubbing the skin raw there?
Any special mods to the anterior side of the socket to make space for the tendons there?

roboleg 09-19-11 04:14 AM

Got your message punkncat. Dont have enough post to reply privately.
I am right bk as of Sept 2010

roboleg 09-19-11 09:18 AM

Hi Martin,

Usually I have to use a hand grinder, 41/2 in, to remove one to two incheson my new sockets. (still not in my final one yet but hope to be in a carbonfiber one this month). Neosporin helps all across the back where the top of thesocket rubs behind the knee. I only use a little and it does not affect theoverall grip of the liner. Besides, with only downward pressure while riding it’snot like it’s going anywhere.

Juan Foote 09-19-11 07:12 PM

Be careful of using products with petroleum in them if you are using a silicone locking liner. Those products will degrade the liner and cause it to form a hole in the area effected. It ruins a very expensive component, and really blows to have a hole come up mid think that liner rubs you raw, wait till you get skin on the exterior cloth. I ended up being off bike for over a year due to a lesion that formed from this same issue, aggrivated by a poor "cycling" trimline.

gbcb 10-02-11 08:08 AM


Originally Posted by benajah (Post 10482940)
The first is that you have a more direct power transfer to the pedal, and also without the springiness of a foot you dont lose as much power. The second advantage is that the cleat is effectively where your heel would be, meaning you don't have to bend your knee as much, cutting back on skin breakdown on the back of your knee

Wow. I want a cycling peg now! The second advantage in particular sounds great. My situation's a bit different since I've got a rotationplasty rather than a standard BKA, but I've definitely had problems with skin breakdown related to "knee"-bending on long rides (my newest leg minimizes this, but it's still something I need to be aware of).

I wonder how much it would cost to get my previous leg converted, since it's just gathering dust in my closet. I've found that getting prosthetic stuff done in China is relatively cheap, but I don't see much in the way of experimentation. Unfortunately I don't have benajah's skills or friends to rely on :)

Juan Foote 10-03-11 06:56 PM

I have been working with my prosthesist to make a "peg" like that, with the cleat on bottom. I just purchased some new cleats and aquired an old MTB shoe to use as a guide. My doc says he thinks there are enough random bits of various metals back in the workshop to make it out of what would otherwise be scrap.

ctstarnes 01-05-14 10:42 PM

I'm a new double bka ... 37 yo previous cat 3 road who lost his feet from cancer ... Long story .., amputation was sept 15 ... Getting my first pair of prosthetics next week. I have a neuropathy I am recovering from as well and it's gonna take me weeks to learn to walk. Then I want to be back on the bike. Are you a double amputee? I am wondering balance issues and interested in your models for peg legs.

Juan Foote 01-06-14 09:03 PM

ct, I don't believe that any of us are double BKA. My biggest concern for you is how you will unclip. It requires a twisting of the heel that we cannot perform when using clipless and platforms have obvious limitations for us. I am sure that where there is a will there is a way and will be glad to help with any specific concerns that I can.

joe bag o donut 02-01-14 05:22 PM

I am currently studying prosthetics in grad school and stumbled across this post. A question I have for benajah is would you find any advantages in a rigid lever(no flex) that advances the cleat a few inches in front of the pedal for a more traditional forefoot placement? Or is the skin irritation behind the knee enough to warrant sticking with the peg leg?


roboleg 02-03-14 01:20 PM

Biking leg
4 Attachment(s)
I am right leg below the knee amputee and have been riding for about 3 years at 150+ miles/wk. I am currently in my third generation prosthetic riding leg. While the are several options that an amputee can choose I can only speak as to what works for me and why. My first riding leg was my walking leg with a riding shoe on it with an spd cleat so I could clip in. This was good for starters but the mechanics that make a flex carbon fiber foot work actually causes extra work for a bicyclist. When walking the weight of the walker "loads" the foot and it lightly springs forward just when you push off. With biking, downward pressure on the pedal loads the foot but there is not a return effect as the loaded energy in the foot is lost at the bottom of the pedal stride and there is no kick off. The end result is that the rider expends the energy to load the foot on the downward stroke but there is no return. Additionally, many amputee riders have difficulty in "pulling up" the pedal on their prosthetic side for a variety of reasons. What is working best for me is a straight leg no flex foot. The pedal cleat is recessed into the foot that allows me to walk on it if I need too. I am trying to attach pics and I hope this explains what works for me. I literally have to use three different legs, one to walk, one to run(25mi/wk), one to ride(150mi/wk).

esther-L 02-28-14 06:02 PM

One of the executives at Soldier Ride is a bilateral below knee amputee. During the 1 Soldier Ride I went to (that was open to public participation) it looked like he uses SPD pedals and MTB shoes.

There is a retired crit racer named Duane Wagner who's a Vietnam-era bilateral BKA. You could try looking for him and asking him which pedal system he uses and how he unclips.

esther-L 03-01-14 12:03 PM

Awesome setup, benajah! I also use frog cleats.

Everyone is different. I am a very long-term amputee. I don't have any issue with trimline on my socket for biking - it's cut low and I don't have prominent tendons/ligaments.
I have not tried peg leg yet, because I don't know if I could walk on one off the bike, since the bathroom is usually at the far corner of a convenience store. I do commuting and recreational rides and a little bit of supported touring.

I have tried mounting the cleat in the toe-most position on biking shoe, but I get more comfort and power with it closer to under the
middle of the foot. Due to being long-term, and having amputation as a child, I do not have much muscle mass padding around the distal end of tibia. Applying force on a lever to a point that is out forward on the foot does not feel comfortable to me.

Like I said, every amputee is unique.

I did put my heel on the pedal before I used clipless pedals.

Originally Posted by joe bag o donut (Post 16459748)
I am currently studying prosthetics in grad school and stumbled across this post. A question I have for benajah is would you find any advantages in a rigid lever(no flex) that advances the cleat a few inches in front of the pedal for a more traditional forefoot placement? ......

riadahmed3624 04-12-14 07:21 AM

I've always wondered how that works... thanks for the post.

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