# Leg length discrepencies



## zoikz (Sep 5, 2003)

I've got relatively mild scoliosis which has resulted in a leg length discrepency around 1.5 inches. During times of heavy training I get lower back pain on the shorter side. Can I shim this problem in my shoes or should I use different length cranks?


----------



## sprocketjockey9 (Sep 16, 2008)

I'd recommend that you go get a real bike fitting from a professional. They know what they are doing and can help solve your problem. Dealing with something that can cause an injury is something you want to leave up to professionals


----------



## zoikz (Sep 5, 2003)

I've already had the local guys do it. Once on a fit system and then tweaked it on a fitting session by a trained technician on my bike. One of the problems is that it is not that apparent when I'm on a trainer, but became really apparent when I'm loggin a lot of hours in the saddle. I ended having to go back to my old specs. I was just wondering if there is a particular length of discrepency when you consider shims versus changing the crank arms. How much of a discrepency will shims compensate for? I'd rather just try one or the other and see if things improve. Another problem is my shoes are pretty snug and the toe box is way too tight when I tried some shims. I'd prob have to get customs to be able to use them (I already have the wide models).


----------



## ukbloke (Sep 1, 2007)

Are you using the wedges that go between the cleats and the bottom of the shoe? I don't see how they would make the toe box too tight. I have 6 of the wedges stacked up to a height of about 8mm on one shoe. You need to use long bolts and really tighten them up, but that has worked out well for me. You can get the bolts at Home Depot or similar. For me they were metric 6mm bolts I think (SPD-SL pedals).

Another tip is to adjust the fore/aft position of the cleat on the shoe so that the shoe on the longer leg is all the way forward (ie. towards the front wheel) while the shoe on the short leg is all the way backwards (ie. towards the back wheel). The cleat position on the shoe has to move in the opposite direction of course. This compensates for leg length discrepancy in the *upper* leg (between hip and knee), while the wedges compensate for a total leg length discrepancy.

If you are trying to address 1.5 inches of discrepancy you will probably need to do both the wedges and the fore/aft.

I'd say that assymmetric crank lengths is the last resort as that involves much more money! Personally I don't think that I would get on with the assymmetry at all, but you never know until you try. After a couple of weeks of tweaking I got everything adjusted perfectly and I don't worry about the discrepancy any more. I've also heard that you only need to put in enough adjustment to account for half of the leg length discrepancy, and that you body and riding style will deal with the rest.

Finally, when you make these changes your saddle height and fore/aft may need to be adjusted too. Record your original settings and make the changes gradually. Watch out for any knee/back pain, and definitely back out changes (and rest) if your knees start hurting.


----------



## zoikz (Sep 5, 2003)

thanks for the great response. I had tried shims in the shoe but it does make sense to put them under the cleat. I'm sure I can rig something at home depot.


----------



## Alex_Simmons/RST (Jan 12, 2008)

You may need custom shoes, one with a much thicker insole than the other.
It is possible and I know of one rider who has done this.

A thing to watch for with lots of shims between the shoes and the cleat is it tends to accentuate the for/aft rocking around the pedal axle (as your foot moves further away from the pedal axle), so the cleat position on that side can become a bit more sensitive than for others.

for some ideas, have a look at some of the items here:
http://www.cyclefitcentre.com/further reading.htm


----------



## velogirl (Oct 14, 2005)

if your discrepancy is dynamic (ie not bone structure in your leg) then you don't want to correct with shims. shim correction is for tibia discrepancy. for femur or dynamic discrepancy, you would correct with cleat positioning. fit your saddle height and fore/aft for your shorter leg. then position your other cleat behind the ball of your foot. 

I'm happy to answer more specific questions if you want to email me off-line.


----------



## iliveonnitro (Feb 19, 2006)

velogirl said:


> if your discrepancy is dynamic (ie not bone structure in your leg) then you don't want to correct with shims. shim correction is for tibia discrepancy. for femur or dynamic discrepancy, you would correct with cleat positioning. fit your saddle height and fore/aft for your shorter leg. then position your other cleat behind the ball of your foot.
> 
> I'm happy to answer more specific questions if you want to email me off-line.


OK I'll bite, since I'm still not great with bike fit.

When would you want to use a shorter crank arm on one side? It almost sounds like this would help in this case.


----------



## velogirl (Oct 14, 2005)

iliveonnitro said:


> OK I'll bite, since I'm still not great with bike fit.
> 
> When would you want to use a shorter crank arm on one side? It almost sounds like this would help in this case.


Never. Although there is one fitter in the US who designs variable length cranks. In my opinion, that is never the solution.


----------



## iliveonnitro (Feb 19, 2006)

velogirl said:


> Never. Although there is one fitter in the US who designs variable length cranks. In my opinion, that is never the solution.


I misinterpreted the OP and thought of Blount's disease, for some reason.

If someone physically has a shorter leg length by 1.5" due to a short femur or tibia, how would you fix it? 1.5" is a little much for spacers on a tibia discrepancy.

Also, how would you adjust a right cleat if a person's quad and soleus are sore on rides? I forgot to mark my new (fixed LOOK-style) cleats and my right side isn't quite right compared to the old setup. There is a slight pain in the inside-posterior part of my knee.

Sorry to hijack the thread between your posts zoikz


----------



## velogirl (Oct 14, 2005)

typically you only correct 1/2 the discrepancy. so, if his difference is 1.5" we would correct to 0.75".

tibia discrepancy = shims

femur discrepancy = cleat offset.

dymanic discrepancy (ie flexibility, scoliosis) = clear offset.

Nitro, could the discomfort be attributed to a difference in float? New cleats have less wear and less float than old cleats. That's where I'd place my money.

Lorri




iliveonnitro said:


> I misinterpreted the OP and thought of Blount's disease, for some reason.
> 
> If someone physically has a shorter leg length by 1.5" due to a short femur or tibia, how would you fix it? 1.5" is a little much for spacers on a tibia discrepancy.
> 
> ...


----------



## iliveonnitro (Feb 19, 2006)

velogirl said:


> Nitro, could the discomfort be attributed to a difference in float? New cleats have less wear and less float than old cleats. That's where I'd place my money.


Nope. I've been running fixed cleats for 1.5 years and have replaced them at least 3-4 times before this. I always marked them, though, but I forgot this time around. Never have I had this problem before.

It was really bad at first, but some manipulation and it's getting better. My next attempt is to angle the toe outward (heel-in) some to rid myself of the inside-posterior knee pain. Then I have to figure out left/right/forward/back for the lower calf pain. It feels like I need to put more pressure on the outside part of my foot, so I'll try that next. One adjustment at a time, though . Just wondering if you had suggestions on that one.

If you don't have the answer to the above problem, maybe you can help with this one. My left phalanges hurts on rides over 2hrs. I'm getting better at dealing with the pain (it used to only be 1 hour). This has been going on since I got my bike a few years ago. It's spread over 2 different pedal setups, 2 pairs of shoes, numerous cleats (fixed and float). I've had custom orthotics as well as SOLE's put in my shoes. It helps with thick wool socks, but does not eliminate it. No idea where to go with this one.


----------



## velogirl (Oct 14, 2005)

I'd refer you to your original bike fitter. S/he probably has a record of your original cleat position and can duplicate that for you.

Now, for the phalanges. I assume you're referring to toes (not fingers)? The toes on your left foot? Which toes in particular (1 = big toe, 5 = little toe)? Do you have this discomfort at any time besides when you're riding? Can you describe the discomfort? Burning? Numbness? Tingling? Does the discomfort continue after you're off the bike? On a scale of 1 (no pain) to 10 (debilitating pain), how would you rate this discomfort?

Lorri


----------



## Alex_Simmons/RST (Jan 12, 2008)

velogirl said:


> Never. Although there is one fitter in the US who designs variable length cranks. In my opinion, that is never the solution.


Never say never.

On my return to riding 4 months ago, I required a short crank (100mm) to start with on my left side before being able to gradually return to a full length crank.

But making a comeback after a busted bones, a trans tibial amputation and riding with a prosthetic will do that  

Fortunately, I can now make my leg any length I like


----------



## velogirl (Oct 14, 2005)

wow! that's quite a story, Alex. I'll have to read your blog to learn more about you.

and, yes, nothing in this world is black & white.


----------



## ukbloke (Sep 1, 2007)

This is my first time hanging out in the coaching forum. You guys are just awesome. If I ever need a bike fit or other coaching advice, I know where to go. Thanks!


----------



## empty_set (Nov 1, 2006)

I began having serious knee and hip pain and went to a physical therapist first. I've got a leg length discrepancy due to a broken back and it made a 3cm difference. I use a thick insole in my right shoe with my mtb shoes and a shim on my road shoes. I've also dropped my saddle a bit. All of the combined have helped out. I'd say the physical therapy helped the most in helping to strengthen and improve flexibility.


----------



## iliveonnitro (Feb 19, 2006)

velogirl said:


> I'd refer you to your original bike fitter. S/he probably has a record of your original cleat position and can duplicate that for you.
> 
> Now, for the phalanges. I assume you're referring to toes (not fingers)? The toes on your left foot? Which toes in particular (1 = big toe, 5 = little toe)? Do you have this discomfort at any time besides when you're riding? Can you describe the discomfort? Burning? Numbness? Tingling? Does the discomfort continue after you're off the bike? On a scale of 1 (no pain) to 10 (debilitating pain), how would you rate this discomfort?
> 
> Lorri


1 - big toe. Only happens on long rides on the bike. Feels like someone took a ball peen hammer and smashed the underside of my big toe. Pain lasts for an hour or so after I get off the bike. On any given day it will be a 2-3 up to a 8-9. It probably averages a 5-6, though.

I don't have an original bike fitter, nor the money to use a professional. Money is tight in college.


----------



## velogirl (Oct 14, 2005)

nitro, has this always happened since you began riding? or since you've been riding a specific bike? or with specific shoes?

what shoes are you wearing? how old are they?

what insoles are you wearing? how old are they?

which pedal system do you ride? how old are they?


----------



## iliveonnitro (Feb 19, 2006)

velogirl said:


> nitro, has this always happened since you began riding? or since you've been riding a specific bike? or with specific shoes?
> 
> what shoes are you wearing? how old are they?
> 
> ...


Old ones were ...actually, I don't remember. They were only like $70 though. The new ones are Deodora labeled under Cannondale Carbon's, which were much nicer. It has happened since the beginning a few years ago, regardless of bike, shoes, or cleats. My current shoes are only one season old. The insoles are maybe 7mo.

Look Keo sprints, new for this season. Happened on my old Look 585's though, too, which was a completely different setup.

I'm glad you are as puzzled as I am on this one. Usually I can nail down the problem, even if it's slow. This one has even my orthopedic surgeon mystified. He was a tool, though, who didn't seem to care much about his patients.


----------



## gh1 (Jun 7, 2008)

my leg length diff is in the femur and cleat position has taken care of any issues with the short leg. good luck


----------



## velogirl (Oct 14, 2005)

how about saddles? now? other bikes?


----------



## iliveonnitro (Feb 19, 2006)

velogirl said:


> how about saddles? now? other bikes?


The saddle wouldn't do it. Happens regardless. I'll just live with the pain


----------



## velogirl (Oct 14, 2005)

iliveonnitro said:


> The saddle wouldn't do it. Happens regardless. I'll just live with the pain


Actually, the saddle could be impinging and causing numbness in your toes.

Or maybe you're just a genetic freak destined to live with it!


----------



## ukbloke (Sep 1, 2007)

iliveonnitro said:


> ... It feels like I need to put more pressure on the outside part of my foot, so I'll try that next. One adjustment at a time, though  ... My left phalanges hurts on rides over 2hrs. ...


The comment about needing to apply more pressure to the outside of the foot plus your tingling in the big toe, makes me think that this is forefoot valgus. Have you tried inserting one or more cleat wedges with the thicker part on the outside of the foot? Take a look at http://www.bikefit.com/index.php.


----------

