Functional leg length discrepancy
 

I have been having around my right side sit bone for a long time. As I got more fit and tried longer climbs and longer distances, the pain has gotten more noticeable. When I revisited the bike fit specialist last week, he said that I have a functional leg length discrepancy from what he could tell. Basically when I lie flat, my legs have identical length but when I go to a sitting position, my right leg is about 3-5 mm longer.

He referred to me see a PT to get this checked out which I will go do when I have the time and the money.

I have no problems with this either walking or running or any other activity, so I am tempted to ask.

Why can't I just buy a 3mm shim kit from Bike Fit and then shim the left cleat by 3 mm? Has anyone tried this and resolved this kind of an issue?

Any comments and pointers would be appreciated.

Thanks in advance,

Bora

Good question. I recently visited a chiropractor for lower back pain and had x-rays done. The chiro observed in passing that my right leg is 7 mm shorter than the left. Again not observable lying flat and caused by hip rotation I guess. He was somewhat surprised no one had picked this up before though it does explain why my right shoe from childhood has always worn out on the outside of the heel. He suggested getting an orthotic insert. He said a heel insert might work but a full orthotic is preferable. Since I'm having major issues with my right knee I'm going to try this....nothing else seems to have fixed it.

i believe that even x-rays have an error of +/- 5mm.

at least i read something like that on the steve hogg website.

google steve hogg and ask him.

If you put a 3mm shim kit in your left cleat then you'll effectively have your saddle 3mm too low on wrt your left leg at the top and bottom of the stroke. May not be a big issue, but might be enough to give you knee issues...?

I think my problem is that my saddle is 3mm too high for the left leg, so if I shim it, it may end up being just right ;)

Thanks, if I read his website right, it looks like functional leg length discrepancy does not show up in X-rays but shows up on the bike.

I get that, I suspect I have something similar, the issue is that the effective leg length is correct currently at the bottom of your pedal stroke but not elsewhere. If I'm understanding your situation you might have a longer left femur, but that is compensated by a shorter tibia/fibula - as if your knee joint is 5mm lower on the left. Does that make sense?

I understand what you mean now. There are three pieces in the geometry. I guess I may have to go see that PT after all sooner than I had planned.
In my case, I think it has something to do with my right pelvis and SI joint but who knows.

i would have another fitter or someone experienced and knowledgeable check out your fit as well. being a "certified fitter" does not make someone good at fitting.

double check basic stuff:
-saddle straight
-no uneven flaws in saddle
-cleat location (remember, feet are typically not the same exact measurements.)
-flexibility (any muscle tightness?)
-making sure you are choosing efficient gearing to pedal
-no functional flaws in shoes
-saddle height

again, check the steve hogg site regarding saddle height.

3-5mm functional LL discrepency? hah.

that is way within the margin of error for measuring that (which should be taken from navel to malleolus). Heck, you have a bigger quad on one side, that will give you 3mm when measuring.

Even a 3mm true discrepency (taken by measuing an xray).... I havent read any research lately, but there have been arguments for several years at what level does it even play a role (last I heard it was 1-2cm).

Do as you wish. But go find a good PT, let them check you out. You have quite a few structures on/around your 'sit bones'. if you are downtown seattle, I know of a good one. I also know one that is very unimpressive who many cyclists go to.

disclosure - I am a physical therapist and a competitive cyclist.

Thanks. I am on the east side. I made a pt appointment for tomorrow.
This pt is also a cyclist so I'm hoping that I will get a resolution on this after a few visits.

Or you could spend $20 and 20 minutes installing the shims and try it. If it hurts, stop.

After all, it's not like the therapist is going to give your short ankle a tug and say, "There. That should even them out."

At the very least, buy a Dr. Scholls insert and shove it in your left shoe and try it.

I did what your thinking about doing and it worked out great. I wasn't about to put out $300 for a fit, so I kept playing with it myself. I went a half mm at a time and ended up with 2mm. It sounds like 3mm is a lot, but if that what it takes, so be it.

I've had chaffing and knee problems for years until I decided to try the shims. I wish I did it sooner. I really don't know how many saddles and bibs I've gone through, to find this out. I hope it works out OK for you. Good luck.

I'm reluctant to listen to a word he says after this trainwreck.

I went and saw the PT today. Very knowledgeable and it helped that he is a serious cyclist. It looks like I need to take my stretching and core exercises more seriously. He said I may still need a 1/8th of an inch shim on the left side. We shall see.

See a chiropractor.

Thanks. The pt I'm seeing is also an osteopath.

After almost two weeks of PT, it looks like it is in fact my right leg that is shorter but only when I am on the bike. The PT gave me some exercises to do and they did some deep tissue massage (which actually hurt like hell for days afterward), I have a follow up appt this week, hopefully I can put this behind me. It has been very frustrating not riding my bike with the nice weather we have been having.

Wish me luck.

use a foam roller for pain. its hurts soooooo gooooooood

Which one do you prefer? The hollow core one, or the ones made completely out of foam?

I just got the book "Complete Medical Guide for Cyclists" by Andy Pruitt. It might be worthwhile to buy this book, and maybe a few others. Surely, the cost is minimal. Anyway, he does discuss the problem of different leg lengths. He indicates that a difference in leg lengths usually shows up as lower back pain. To quote the book, pg 69:

"When should I shim a cleat?
If you have a leg length inequality of 3mm or greater accompanied by back pain, you may need a shim... In cycling, if the LLI is less than 6mm, I don't use a shim. Instead, I move the cleat on the side with the short leg forward on the shoe sole 1-2mm... If the LLI is over 6mm, it requires a shim."

I got the book used on Amazon for probably $6, may as well try it!

24hr fitness sells one inside for about $20-25. its awesome.

before that, i tried (and returned w/in one day) foams rollers from sports authority and the like...they were crap: too soft.

Had a friend that due to an accident had a left 1.5 cm shorter, he was telling me that he was setting the saddle height as if he had both legs equal then lower the saddle 7 to 10 mm to compensate the shorter one. The next thing was that at the beginning he said he had a lot of pain obviosly but he sucked up until the pain was gone forever.

Another friend had a similar problem, when he seats his hip rotates, 5 mm shorter right away. He sets the saddle considering the shorter leg. so if you look at him from one side he is ok, from the other side he look kinda too low in the saddle. He live with that.