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  1. #1
    Be the Bike BikeZen.org's Avatar
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    Short leg

    One of my legs is about 2cm shorter than the other. (This wasn't so until March, when a bike accident and the surgery that followed change my femur length -- see the picture below.) I'm looking for ideas about how to ride "normally" again.

    Options:
    -- Orthotics. The problem with these is that adding 2cm inside the shoe means my shoes don't fit comfortably. Perhaps I need different shoes with taller heel boxes?
    -- Change cleat location. I've moved the cleats on my short leg several mm forward (towards my toes) and on my long leg slightly back. It just doesn't feel right, though.
    -- Consult a professional. I'm seeing PT folks now. They gave me heel lifters, which have the same challenges as orthotics (shoe fit is problematic). I'm considering seeing other folks, like Dr. Pruitt.
    -- Do nothing. This means rotating my pelvis and/or plantarflexion to compensate. I've tried this, and it doesn't feel good. I enjoy long rides (I was planning to do 600k this summer), so a tilted pelvis or foot is a poor solution.
    -- Cleat risers? Perhaps increasing the distance from the peddle spindle to the base of the shoe would work?
    -- Other suggestions?
    Attached Images Attached Images
    Last edited by BikeZen.org; 07-13-07 at 08:38 PM.

  2. #2
    Senior Member BlazingPedals's Avatar
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    If your left thigh is shorter, you can put a 2cm shorter crank on the left side. I know you can get 155 mms, because I have a set.

  3. #3
    Be the Bike BikeZen.org's Avatar
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    I thought about that. It kinda' works, because then when the peddle is farthest away, it won't be as far as it would be otherwise. But it's still a bit awkward. The idea is that I'd like to somehow virtually "lengthen" my shorter leg so the crank feel and rhythm is the same as it used to be, regardless of where my feet are in the stroke.

    With a shorter crank, then I would have to reach FARTHER to get to it when the crank is turned TOWARD me. To compensate, I would need a longer crank on the upstroke. But if the crank is LONGER, then I would have to reach FATHER to get to it when the crank is turned AWAY from me. Of the two options, clearly the shorter crank is the better option, though still not ideal.

    Keep those ideas coming!
    Last edited by BikeZen.org; 07-13-07 at 11:07 PM.

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    Pedal block

    Cut a piece of wood or plastic large enough to make up most if the leg-length difference, bolt it to the pedal, attache your cleat atop that. If there's no way to use a cleat, switch to something like PowerGrips.

    Maybe that's what you meant by a "cleat riser?" I called it a pedal block because that's what we called them when we were very little kids - and many of us rode hand-me-down bikes that didn't quite fit.

  5. #5
    Senior Member BlazingPedals's Avatar
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    My brother lost a couple of inches of shin bone in a motorcycle accident. He has specially built-up shoes. If you get a thicker sole, you want it to be thicker on the outside, because as you stated, it'll change the fit of the shoe if you put it on the inside.

  6. #6
    Recumbent Evangelist
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    Maybe you could clamp one "donor" pedal onto the existing pedal. They're about 2cm high, aren't they? Talk to a machinist instead of a doctor.
    www.rebel-cycles.com

    The official Canadian dealer of TW-Bents recumbent bicycles!

  7. #7
    POWERCRANK addict markhr's Avatar
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    Previous leg length thread

    Leg lenght discrepency

    Quote Originally Posted by markhr
    powercranks adjustable "adjustable length crank which easily changes from 85mm to 220mm"

    www.powercranks.com

    much less stress on your knees as you're reliant on a lot more muscles and the power is spread smoothly across the whole pedal stroke rather than just mashing or pedalling squares

    http://www.pezcyclingnews.com/defaul...lstory&id=4331

    shameless POWERCRANK plug
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    Don't run red lights, wear a helmet, use hand signals, get some cycle lights(front and rear) and, FFS, don't run red lights!

  8. #8
    Greybiker
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    According to your note, your bone loss was in the femur, but your picture seems to show a length difference at the knees. Where was your loss? if femur, was it proximal (near the hip) or distal (knee)? how has this affected function at your hip and knee?

    The issue in recovering "normal" biomechanics is that it is difficult to compensate for loss in the length of the thigh. Adding length at the foot effectively lengthens the lower leg during the upper half of the pedal stroke and the entire leg during the lower half. There's no way that the stroke effects of a shortened femur can be effectively normalized. Lifting the buttock above the unaffected leg could get the knees closer to the same axis but the discomfort coudl be substantial. A recumbent with the seat slightly angled so as to bring the shortened leg closer and the longer further away would seem to me to be a reasonbly good possibility. You need a capable mechanic with lots of parts -- cranks, saddles, etc. -- and some patience. And please, let us all know what you find out.

  9. #9
    Be the Bike BikeZen.org's Avatar
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    AWESOME INPUT everyone. I knew the Internet was good for something!

    I have some specific responses and questions, then a summary of where I am today...

    Quote Originally Posted by edgross208 View Post
    According to your note, your bone loss was in the femur, but your picture seems to show a length difference at the knees. Where was your loss? if femur, was it proximal (near the hip) or distal (knee)? how has this affected function at your hip and knee?
    My femur is shorter due to bone loss near the hip -- just below the superior trochanter. Pre- and post-op x-rays appear below.

    Quote Originally Posted by edgross208 View Post
    The issue in recovering "normal" biomechanics is that it is difficult to compensate for loss in the length of the thigh. Adding length at the foot effectively lengthens the lower leg during the upper half of the pedal stroke and the entire leg during the lower half. There's no way that the stroke effects of a shortened femur can be effectively normalized.
    I get the gist of what you are saying but don't understand the specifics. Please elaborate.

    --------------------

    Other generous contributors to this thread have given me some good ideas to explore. In general, I'm tending towards the idea of adding a custom-made shim/block between my shoe and my cleat, just to see how it feels. If it works out, then I'll explore buying a professional shim/block -- but that will mean changing my pedal system. (I currently use bebop, but used speedplay for many years and so could switch back to them without much resistance.)

    Here's a summary of my findings to date, based on this thread and related threads suggested above:

    1) increase length from pedal to shoe on the short leg:
    -- speedplay shims: http://www.speedplay.com/index.cfm?f...home.zeroshims
    -- cleat block: http://www.hscycle.com/Pages/cantsandwedges.html
    -- get creative and make something (clamp on a pedal; manufacture a block; etc.)
    CHALLENGES: either custom-made, or specific to certain pedal manufacturers

    2) get shorter cranks on both sides and add "drop pedals" to the crank on my longer leg
    -- drop pedals: http://www.hscycle.com/Pages/cantsandwedges.html
    CHALLENGES: drops are hinged (?) so can't pull up "normally" on the pedals. I may call them to discuss: 800-438-4399

    3) consider having a shorter crank on the side with my short leg
    -- buy one shorter crank on the left side
    -- get an adjustable-length crank (powercranks.com) which is adjustable from 85mm to 220mm [markhr, 11-1-06]
    review: http://www.pezcyclingnews.com/defaul...lstory&id=4331
    problem: cost is $1100
    CHALLENGES: different length crank on one side not recommended (see bokes 10-29-06 at Leg lenght discrepency)

    4) reading recommendations:
    Andy Pruitt's Complete Medical Guide for Cyclists: http://www.amazon.com/Pruitts-Comple.../dp/1931382808

    Keep those ideas coming!
    Attached Images Attached Images

  10. #10
    POWERCRANK addict markhr's Avatar
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    Quote Originally Posted by BikeZen.org View Post
    ...3) consider having a shorter crank on the side with my short leg
    -- buy one shorter crank on the left side
    -- get an adjustable-length crank (powercranks.com) which is adjustable from 85mm to 220mm [markhr, 11-1-06]
    review: http://www.pezcyclingnews.com/defaul...lstory&id=4331
    problem: cost is $1100
    CHALLENGES: different length crank on one side not recommended (see bokes 10-29-06 at Leg lenght discrepency)
    ...
    Powercranks have a very healthy second hand market - you don't have to buy new - as I type there are 2 pairs on the US version of E-bay for substantially less than new.


    While I may be a powercrank addict not everyone else is so the cheaper option would be just buy 2 pairs of cheap cranks (one short pair and one long pair). Try to get the exact difference so you don't have to do ridiculous things with shims but

    more random examples of cranks with 20mm difference

    160mm isis cranks http://www.trialsman.co.uk/products.asp?cat=24

    180mm isis cranks http://www.raceface.com/components/c...deus-crank.htm


    another expensive option but it is a silver bullet

    fully custom crankset http://www.zinncycles.com/cranks.aspx



    google is your friend
    shameless POWERCRANK plug
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    Don't run red lights, wear a helmet, use hand signals, get some cycle lights(front and rear) and, FFS, don't run red lights!

  11. #11
    Be the Bike BikeZen.org's Avatar
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    Solution obtained: self-made shim!

    Cheap and fast method: install an electrical conduit nipple (similar to this) between the shoe and cleat. Use two 25mm screws to secure. Cost: less than $2. Time: less than 2 minutes.

    Problems with cheap and fast method:
    -- hot spot on the sole of the shoe, owing to the smaller surface area pressing into the shoe
    -- cleat rotates on its own during riding

    Cheap and slower method: same as above, but use these layers (starting at the sole of the shoe) with the 25mm screws running through all 5 layers.
    1) face plate of old belt buckle. This is a dress-pant buckle, not a yee-haw 2 lb. western rodeo buckle! Use a Dremel tool to cut off everything except the face plate. Drill two holes for the cleat screws. Flip the buckle so it curves the same way as the sole of the shoe.
    2) double-sided tape on the buttom of the nipple (see below). This discourages nipple rotation.
    3) aforementioned electrical conduit nipple. Dremel the side of the nipple that presses against the cleat so that it has the same curvature as the cleat. Also, use the Dremel tool to notch the nipple so the cleat grips fit into the nipple like a jigsaw piece.
    4) small square of industrial strength velcro (the bristly side, not the fuzzy side) taped to the back of the Bebop cleat. This discourages cleat rotation.
    5) the cleat itself

    All problems solved! Only challenges that remain (as with all shim solutions):
    -- difficult to walk in the shoes (imaging walking in high heels, except the heel is in the front, not the heel)
    -- added weight. Good for strength training, though! (Possible solution: substitute a PVC pipe for the electrical conduit nipple. This may not be as robust, however.)

    Thanks for your ideas, folks!

  12. #12
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    Explanation of my previous post re: femoral shortening

    I hope this will be a bit clearer: When your leg is flexed, from the top of the pedal stroke to the point where your knee forms a 90 degree angle, the difference in the length of your thighs affects the position of your knee and not the length of the entire leg (assuming that the lower leg lengths are the same). Further clarification: when your cranks are exactly horizontal, the distance from your pelvis to your feet is about the same but the distance from your pelvis to your knees is less on the short side. So a shim at the foot end will not compensate for the difference; only something that moves the hip on the short side a little bit forward will put the knees in the same place.

    Once you get past that horizontal point (actually, to be precise, the point where the pedal position is more than 90 degrees from the mean position of the thighs) the thigh length contributes increasingly to overall leg length and when your legs are nearly straight, at the nadir of the pedal stroke, the difference is most expressed. Here a shim is helpful but, if you follow the picture, the extra length required to equalize the two legs becomes greater as the leg gets straighter -- a dynamic variable you can't really compensate for readily (without, say, an eccentric crank -- not me -- or some other varying-length drive lever).

    The best way I can figure to offset the shortened leg would be to place a support that puts the hip of the affected side a little bit forward of its normal position on the seat. This should be calibrated so it will have the effect of moving the knees to the same position when each is at the 90 degree mark (cranks perpendicular to the axis of the legs) and also should equalize the distance from hip (back, not side) to crank in the fully extended, bottom of the stroke position.

    Try putting a piece of 1 inch wood behind your seat cushion just to see if you can get into the position. It might turn out to be uncomfortable to keep your torso and neck slightly turned while riding but it's worth a try. If you can't get the piece of wood under padding, you could just wrap a piece of 1x2 or 1x3 in something soft and put it into your short just below the waist on the shortened side: like sitting on a thick wallet. This should give you information at least, maybe some help in resolving the problems.

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