Leg injury - leg size difference?

I’ve been dealing with right leg injuries for the better part of three years. Thinking back on all my training and racing I’ve pretty much had some sort of injury to this leg since I started…every time I do a long (100+ miles) bike ride my knee blows up, any time I do a big cycling week I’ve been hurt, increasing distance on the run leads to knee injuries…and through it all the leg always feels ‘off’.

I’ve been to a number of ortho’s and PT’s with no success, and I’ve been seeing a chiro for 3+ months which doesn’t seem to be leading anywhere. My bikes have been fit a few different times from different shops and I’ve had multiple running gait analyses done to improve any form/imbalance/stability issues. Now, I can keep my training volume low–runs of 6 miles or less, no more than two days in a row running, short and/or low intensity bike rides, etc–but that’s no fun and no way to improve.

So all that said, here’s my latest crazy idea as to what might be causing this: during a gait analysis a few months back a running coach had what sounded like a throw-away line: ‘you’re right thigh is bigger than your left, I’ve heard that happens alot with cyclists’. I thought nothing of it but maybe…

My right thigh–measured mid thigh–is 22.5"; the left is 21.4". 1.1 inches…is that much of a difference? Might I be relying too much on my right leg, overtaxing/overtraining it in relation to the left?

Keep in mind that it’s not a ‘knee’ injury per se. As I type this the right groin/upper thigh area is tender and my ankle’s been a bit sore. The leg is always ‘hurt’, top to bottom, but what ultimately keeps me off the bike and out of running shoes is when the knee finally blows up.

Any thoughts on any of this? I’m desperate here, I told myself 2011 was the year I’d finally figure this injury out and I’m still without a solution a month into 2012. The last thing I want to do–I don’t even want to think about it–is give up the sport and the training, it basically keeps me sane. But I can’t keep up this roller coaster of getting hurt every three months and feeling injured the rest of the time, it sucks.

It sounds to me like you’ve got a muscular imbalance, contributing to that size difference in your right v. left Quads. The right side like you said is exerting more force than left.
Ever try to do single leg spins? Try to get your spinning leg flowing freely in a smooth cycling motion without any hinderance at the top or bottom of pedal stroke.
Have the PT’s ever had you perform single leg balance and dominance drills?

Have you ever heard of Muscle Activation Techniques? (MAT). It evaluates and treats muscular imbalances to try to create symmetry. Your right side should be same as left in theory if muscles are functioning properly. MAT evaluates for areas of compensations and then treats the weak muscles and positions.

What you need to keep in mind is that the fact your groin and ankle bother you makes perfect sense. Think about it. Your knee joint essentially does one thing, it flexes and extends. Not a lot of rotation or lateral movement happening at the knee and when there is, bad things usually happen. Therefore, if your hip muscles are not doing there job creating “tight hips” and the same thing with the foot ankle (plus the fact that most people use “stability control” shoes to limit the motion even more). Now the poor knee gets the crap kicked out of it b/c it can’t compensate really. How could it? It can’t make up for lack of control above and below it when it only has one motion! Take the ankle for instance. Most people have limitation in ankle dorsiflexion. Ok. well it can make up for that by increasing the motion in subtalar pronation. no so much with the knee… in other words, address the weaknesses above and below the knee, and it will start doing much better (how much better will be determined by how much damage has been done due to the compensatory stress being placed on it)>

It sounds to me like you’ve got a muscular imbalance, contributing to that size difference in your right v. left Quads. The right side like you said is exerting more force than left.
Ever try to do single leg spins? Try to get your spinning leg flowing freely in a smooth cycling motion without any hinderance at the top or bottom of pedal stroke.
Have the PT’s ever had you perform single leg balance and dominance drills?

I did alot of single leg spins last winter, my old coach believed they helped create a more efficient pedal stroke. I was consistently stronger on the right side–i.e. if I did 30 seconds at 180w on the right I’d generally have a tough time holding more than 160w on the left.

The PT’s did have me do single leg drills–strength and stability stuff. It was always even, though, so if I did 10 single leg squats on the right I’d do 10 on the left. Would it make sense for me to either do some of these drills focusing just on the left, or maybe start with the left, perform to failure, then do the same amount on the right?

Thanks so much for the reply, I appreciate it.

Have you ever heard of Muscle Activation Techniques? (MAT). It evaluates and treats muscular imbalances to try to create symmetry. Your right side should be same as left in theory if muscles are functioning properly. MAT evaluates for areas of compensations and then treats the weak muscles and positions.

What you need to keep in mind is that the fact your groin and ankle bother you makes perfect sense. Think about it. Your knee joint essentially does one thing, it flexes and extends. Not a lot of rotation or lateral movement happening at the knee and when there is, bad things usually happen. Therefore, if your hip muscles are not doing there job creating “tight hips” and the same thing with the foot ankle (plus the fact that most people use “stability control” shoes to limit the motion even more). Now the poor knee gets the crap kicked out of it b/c it can’t compensate really. How could it? It can’t make up for lack of control above and below it when it only has one motion! Take the ankle for instance. Most people have limitation in ankle dorsiflexion. Ok. well it can make up for that by increasing the motion in subtalar pronation. no so much with the knee… in other words, address the weaknesses above and below the knee, and it will start doing much better (how much better will be determined by how much damage has been done due to the compensatory stress being placed on it)>

I appreciate the reply, great information! I’ll have to look into MAT, sounds like a good option to explore.

The thing is, my right leg has more flexibility–the hip flexors, ankle dorsiflexion, etc. So this knee compensation should theoretically be happening on the left side, correct? But as I said, the right thigh/leg is also stronger than the left so my current theory/obsession is that the difference is putting more stress on the right side and leading to these injuries. We’ll see, maybe this MAT treatment will do the trick…

All good thoughts previously. Have you ever been analyzed for a leg length imbalance? Even a slight difference in leg length (which is quite common btw) can result in one leg being in the proper position and working effectively, while the other is “off” and thereby subject to recurring injury. If you find that you have a significant difference in leg length, you can add cleat shims to correct the imbalance on the bike, and look into custom inserts to correct the imbalance on the run. Best of luck!

I tend to look at it this way— I played soccer as a youth, and still do to this day, however not as much. I kick with my right foot, primarily, leaving my left foot to stabilize my kicking leg and entire body during the phase. That leg is a balance point, flexibility hasn’t been it’s forte for a long time, whereas conversely the right leg has had to find that ball each and every time I kick it.

Many PT’s, MD’s, DO’s and like myself, Personal Trainers, look at the body as one whole functional unit. It’s considered a Kinetic Chain. When one link is weak or broken, the rest of the chain is thrown off.
Ask a PT, maybe one on ST can reaffirm my belief that you need to independently train not only that left leg, but your entire body differently until cohesion can exist (pelvis especially). I would start with stability exercises followed by Light strength Endurance training. Keep focusing on that stability for the whole body, go back to it once or twice a week in your workouts.

Performing to failure each and every time you are working out that leg may not be the best bet. Try for -1 to failure, or even less. No need to overload the body each and every time. That leads to overtraining, and potential muscular imbalances.

Just a thought…if you are having trouble with your left quad not being what it “should be”, do you have any issues with the left hamstrings, i.e. the antagonist to the agonist? If you have misfires and pull that opposing muscle, its termed Altered Reciprocal Inhibition. One is working full power and elongates (eccentrically moves) where the other shortens (concentrically contracts) but at incorrect times, lengths, etc.

All good thoughts previously. Have you ever been analyzed for a leg length imbalance? Even a slight difference in leg length (which is quite common btw) can result in one leg being in the proper position and working effectively, while the other is “off” and thereby subject to recurring injury. If you find that you have a significant difference in leg length, you can add cleat shims to correct the imbalance on the bike, and look into custom inserts to correct the imbalance on the run. Best of luck!

Thanks for the response, and yes, I do have a leg length discrepancy. It’s not a big difference but the running coach who did my latest gait analysis mentioned using custom inserts as a last-ditch effort if all the exercises didn’t help. I’m a bit leery of getting, essentially, lifts for my bike and running shoes, though…don’t they essentially mask imbalances, and eventually lead to even worse differences? I’m certainly willing to try them–anything’s better than being hurt over and over–but I’ve kept it on the back burner because of those concerns. Am I misguided in those thoughts?

Contrary to what many people will tell you, very few people have a TRUE leg length discrepancy. The only way to tell for sure is to take a full leg X-ray and actually measure the bones. Most true leg length discrepancies of any significance were caused by a major fracture or disease.

Increased tension of muscles (due to instability) around the pelvis can change apparent leg length. Be careful with any inserts or other extrinsic changes. Your body is just doing the best it can with in it’s current state. If you do not deal with the reason for the compensations (i.e. weaknesses) then the inserts will only create more problems. The weaknesses may just get weaker and now you have limited the body’s ability to compensate.

Contrary to what many people will tell you, very few people have a TRUE leg length discrepancy. The only way to tell for sure is to take a full leg X-ray and actually measure the bones. Most true leg length discrepancies of any significance were caused by a major fracture or disease.

Increased tension of muscles (due to instability) around the pelvis can change apparent leg length. Be careful with any inserts or other extrinsic changes. Your body is just doing the best it can with in it’s current state. If you do not deal with the reason for the compensations (i.e. weaknesses) then the inserts will only create more problems. The weaknesses may just get weaker and now you have limited the body’s ability to compensate.

Yeah, that’s kinda what I was thinking, thanks for the good explanation. I’d get inserts if it’s an absolute last ditch effort to keep competing in the sport but I think I still have a few options to explore before I reach that point.

Contrary to what many people will tell you, very few people have a TRUE leg length discrepancy. The only way to tell for sure is to take a full leg X-ray and actually measure the bones. Most true leg length discrepancies of any significance were caused by a major fracture or disease.

Increased tension of muscles (due to instability) around the pelvis can change apparent leg length. Be careful with any inserts or other extrinsic changes. Your body is just doing the best it can with in it’s current state. If you do not deal with the reason for the compensations (i.e. weaknesses) then the inserts will only create more problems. The weaknesses may just get weaker and now you have limited the body’s ability to compensate.

I had full leg length x-rays in August as I was having surgery to realign my left leg due to significant arthritis. My orthopedic surgeon (Harvard Teaching Doc specializing in arthritis) measured my legs both were 86.2 cm and he thought how unusual that was as most folks are about 10 mm difference between legs. My surgery was a High Tibia Osteotomy and a Tibia Tibuclar Osteotomy which will make my left leg about 8 mm longer which should be close to length prior to loss of cartilage and the way my leg adapted to that.

Have you been to a PT that specializes in functional movement patterns?

I saw 4 PTs, 6 docs trying to get some answers with what was wrong with my knee and how to deal with it. One PT stood out as he is an IM but more than that he evaluates movement and look at the whole chain to see what is causing the issue which is often not the area the injury.

My left leg is about 1/2 cm longer than my right, and I’ve noticed that although my right leg is my stronger leg, when I’m on the trainer, I get more power from my left leg. Maybe a saddle height adjustment necessary?

Just a thought…if you are having trouble with your left quad not being what it “should be”, do you have any issues with the left hamstrings, i.e. the antagonist to the agonist? If you have misfires and pull that opposing muscle, its termed Altered Reciprocal Inhibition. One is working full power and elongates (eccentrically moves) where the other shortens (concentrically contracts) but at incorrect times, lengths, etc.

Hmm ‘Altered Reciprocal Inhibition’ sounds scary. How do you test for this?

I’ve been struggling with the same problem for 14 years.

After my cycle on Saturday I came home and walked into the kitchen and my mother asked me was my knee swollen because even through my cycling leggings she should see the size difference in the muscles of my quads.

Left leg is a lot smaller(Will measure it later). Hamstring goes on it if I ever run, so I dont unless its a triathlon. I only train the swim and cycle now, and despite that it nags at me constantly. After every triathlon(where I have to run) I cant do anything because of my left hamstring being very sore for 1-2 weeks. Even weekly pilates leave my hamstring a tiny bit sore. I do have less stability when standing on my left leg as opposed to my right. I would love to find the solution too.

I had full leg length x-rays in August as I was having surgery to realign my left leg due to significant arthritis. My orthopedic surgeon (Harvard Teaching Doc specializing in arthritis) measured my legs both were 86.2 cm and he thought how unusual that was as most folks are about 10 mm difference between legs. My surgery was a High Tibia Osteotomy and a Tibia Tibuclar Osteotomy which will make my left leg about 8 mm longer which should be close to length prior to loss of cartilage and the way my leg adapted to that.

Have you been to a PT that specializes in functional movement patterns?

I saw 4 PTs, 6 docs trying to get some answers with what was wrong with my knee and how to deal with it. One PT stood out as he is an IM but more than that he evaluates movement and look at the whole chain to see what is causing the issue which is often not the area the injury.

I’m not entirely sure if the PT’s I saw specialized in functional movement patterns but I’m the last gait analysis I had the PT definitely focused on the whole chain. My left shoulder dipped when I ran and I carried the right shoulder much higher. I’ve since ironed out imbalances with my shoulders and low back but it hasn’t alleviated the leg pain.

That’s crazy about the leg length difference, hopefully you’ve made a full recovery and the arthritis has improved. I often think all my issues stem from an injury when I was 14, my left foot was run over by a van (weird, long story), I was in a cast for four months and I don’t think I’ve ever regained the strength and flexibility of that leg and have been overcompensating with the right ever since. I just don’t know what to do about it at this point.

Hmm ‘Altered Reciprocal Inhibition’ sounds scary. How do you test for this?

I’ve been struggling with the same problem for 14 years.

After my cycle on Saturday I came home and walked into the kitchen and my mother asked me was my knee swollen because even through my cycling leggings she should see the size difference in the muscles of my quads.

Left leg is a lot smaller(Will measure it later). Hamstring goes on it if I ever run, so I dont unless its a triathlon. I only train the swim and cycle now, and despite that it nags at me constantly. After every triathlon(where I have to run) I cant do anything because of my left hamstring being very sore for 1-2 weeks. Even weekly pilates leave my hamstring a tiny bit sore. I do have less stability when standing on my left leg as opposed to my right. I would love to find the solution too.

Sorry to hear about your injuries, I know firsthand how frustrating it is to have a recurring injury that you just don’t know how to fix. If you haven’t already you should definitely find a good PT and see if they can help your rebalance things, it sounds like your issue is a general lack of strength on one side, so the left leg can’t support the same load that the right side can and ultimately leads to injury.

I’m going to look more into the MAT treatment, if it helps with this sort of strength imbalance I’ll be sure to post it here.

Increased tension of muscles (due to instability) around the pelvis can change apparent leg length.

If you are standing up straight and relaxed, and one hip bone is lower than the other, how can muscle tension cause that?

Increased tension of muscles (due to instability) around the pelvis can change apparent leg length.

If you are standing up straight and relaxed, and one hip bone is lower than the other, how can muscle tension cause that?

Please don’t take this in a demeaning manner, but how do you think we stand erect? And what do you think holds the bones in position? Muscles are always contracting, it is just a matter of how much. If they are not, we are in a lot of trouble (or dead:) The constant state of contraction is what allows us to not collapse. Even when we sleeps all the muscles are still under low level tension

Do me a favor. Stand up in a “relaxed” position preferably barefoot or in socks. Cup your hands on top of your illiac crests (top of the “pelvis” where the love handles are:) Now, raise one heel (not the foot, just the heel) up off the floor just an inch or so. What happened? The pelvis moved, did it not? What caused that? Muscle tension (or contraction… same thing essentially). Did you change the actual length of your leg by doing that? Of course not, the bone length did not change. Make sense? The body protects for weakness/instability by increasing tension where needed. Eliminate the need, and the tension goes away. Never need to stretch then. It’s a beautiful thing!:slight_smile: I don’t want to argue whether stretching is good or bad… a whole other discussion but wouldn’t it be great not to NEED to stretch? To not feel that tension? It can happen.

No doubt he probably has muscle imbalance at the pelvis, but it is likely caused by a true leg length discrepancy. A traumatic injury at the age of 14 (ran over by car!) could certainly alter bone growth. Leg length discrepancy can be measured by a skilled clinician by measuring in supine position and measuring bony landmarks so that muscle shortening is not a factor in the measurement.
So the easier intervention could be a heel lift. Spend some money on a legitimate professional clinician rather than on a one-size-fits-all muscle activation theory.

Do me a favor. Stand up in a “relaxed” position preferably barefoot or in socks. Cup your hands on top of your illiac crests (top of the “pelvis” where the love handles are:) Now, raise one heel (not the foot, just the heel) up off the floor just an inch or so. What happened? The pelvis moved, did it not? What caused that? Muscle tension (or contraction… same thing essentially). Did you change the actual length of your leg by doing that? Of course not, the bone length did not change. Make sense?

No, it does not make sense. If I raise the heel on my short leg, I can even them out, but this only proves that the lengths were different to start with.

When I’m standing on my heels, there is a continuous length of bone and joints on each side that are in as good alignment as they can be, and they are supporting the weight of my body. If my hip bones are at different heights, then this can only be caused by leg bones (or joints) being different lengths.

No, it does not make sense. If I raise the heel on my short leg, I can even them out, but this only proves that the lengths were different to start with.

When I’m standing on my heels, there is a continuous length of bone and joints on each side that are in as good alignment as they can be, and they are supporting the weight of my body. If my hip bones are at different heights, then this can only be caused by leg bones (or joints) being different lengths.

I love helping people understand this!. however, it can be challenging via written words… I wish I could evaluate your range motion and test some of the muscles to help you understand.

By raising the heel on the short leg, you didn’t actually change leg length, you changed the amount of tension on muscles along the chain and also changed the position of the pelvis. It is POSSIBLE there is a leg length issue, however unlikely. If you have a measurable diff with full length x-ray, then we can talk about a SHOE lift, but a heel lift only raises the heel up… you would want to shorten the entire leg and not put your foot in a position of plantar flexion all the time.

Now you also have to take into consideration that the problem could be related to foot/ankle motion/muscle tension (among a lot of other possibilities). But take the ankle. What if you have a big limitation in ankle dorsiflexion at the Talocrual joint? When you stand up your talocrual (ankle) joint should be at 90 degrees, otherwise you need to compensate just to stand up. When you raised your heel up you took the ankle in to plantar flexion thereby potentially decreasing the tension at the hip. So you can do a heel lift and it will “look” better at the hip and maybe feel better for a while… but this will lead to adapative shortening issues at the ankle and a whole new can of worms has just been opened that will mess with your mechanics big time.

My main point is that FAR too many people are “diagnosed” with leg length discrepancies when that was not the real problem… they are prescribed heel lifts or orthotics and never address the real causes… then they end up with a host of other issues related to this change in mechanics.