I’ve worked with a lot of runners who have leg length discrepancies, which can certainly wreak havoc on an athlete. However, leg length differences can result from a few problems and cause a variety of symptoms. Here are some answers for those questioning their leg length and potential solutions for those struggling with an uneven gait.
What is a leg length discrepancy and where does it come from?
Generally, we see differences in leg length coming from two different sources. The first is a true leg length difference where the long bones have grown into two different lengths. This is pretty rare, as I haven’t seen a lot of people with a true difference in leg lengths. The gold standard method to diagnose this problem is with certain imagery, where a doctor actually measures your bones after a scan and compares each leg side-by-side.
The second and more common way that we see leg length differences is by looking at the pelvis. Sometimes, one side of the pelvis can be rotated forward, effectively lengthening that leg relative to the other. I’ve seen this a lot, and it can definitely set someone up for potential problems down the line.
What are the symptoms when someone has a leg length difference?
When we talk about the symptoms of someone who has a leg length difference that is truly anatomical, they might experience more low back pain and knee pain on the side that is longer, as well as a feeling of having to “swing” their leg around out to the side in order to clear their foot while walking and running. Because one leg is longer, that will propagate up to their pelvis, basically giving them a hip hike on the same side, making their low back muscles tight and leading to pain. Because the leg is longer, they will also have to whip their leg around and out to avoid tripping, which is called circumduction. This is pretty common with people who have a true leg length discrepancy.
Those who have an asymmetrical pelvis leading to a leg length difference may have similar symptoms as someone with true anatomical differences. However, there are other things the person may feel that indicate an anterior rotation of the pelvis as the main culprit. Because the pelvis is rotated forward, we see changes in the muscle dynamic across the pelvic and lumbar regions. For simplicity’s sake, let’s say a person is anteriorly rotated on the right. Because the pelvis is rotated forward on the right, all the structures on the front of the leg are dropped down, making the leg appear longer. The back of the pelvis will also be higher because of that rotation.
This downward rotation at the front and upward rotation at the back will tighten and lengthen certain muscles. People will often complain of a tight and painful low back, tight and painful hip flexors, tight quads and knee pain. In this position, the gluteal muscles are long and weak, so the person might start to get an angry Piriformis as it tries to compensate for the weak butt. The hamstring will be more stretched out because of the rotation, and the person will report chronically “tight” hamstrings.
Some of the running injuries that we see when people have leg length differences include: low back pain, Piriformis syndrome, knee pain, hamstring strains, calf strains, Achilles tendonitis, Illiopsoas pain and foot problems, almost exclusively on one side.
Lastly, one of the big things that helps me find the source of leg length difference: duration of symptoms. If someone has been dealing with their problems since they were a kid, I might lean toward true anatomical difference in leg length. If there was a specific event where the hip was loaded excessively in the not-so-distant past, or, if it was a woman who is post-partum and the symptoms started shortly after, then I’m going to lean more toward a pelvic asymmetry.
What can be done for leg length differences?
If you have a true anatomical leg length difference, the treatment is pretty straightforward. A lift in your shoe on the shorter side will even out your legs and pelvis, helping to alleviate your symptoms. Strengthening your core and glutes and making sure your walking and running gait are spot-on will also help.
If you have an anterior rotation to the pelvic innominate leading to a leg length discrepancy, there are a couple of things to work with. The first thing I do is correct the asymmetry. This is done through a variety of manual therapy techniques to bring the pelvis into alignment. I typically use what are called muscle energy techniques to adjust things. This is a combination of me pushing and pulling and you pushing and pulling in specific directions to move the pelvis. I really like these techniques, as they are gentler than a true pelvic manipulation, though I sometimes need to do this if someone is really “stuck.”
Once the pelvis is symmetrical, the leg length discrepancy is gone and we can get started on learning how to engage your core and glutes again, strengthen those areas, change gait patterns if need be and get back to running (hopefully) without any issues.
These are a few of the ways we see leg length differences and what can be done to keep you running. To get back to the original question: Is it worth investigating whether or not my legs are the same length? I’d say if you are experiencing any of the above symptoms or have some of those injuries on one side, it would be worth seeing if leg length is a contributing factor to your issues. Until next time, see you on the trails!
Medical Disclaimer: What I write here in no way substitutes for an in-person, thorough evaluation by a licensed physical therapist. As with many body issues, there can be multiple factors involved with your aches and pains, and, in some cases, more serious underlying conditions that can be manifesting as physical symptoms. It is always best to have a PT that you can see when you have concerns, so that you can make sure your personal situation is being addressed appropriately and safely. This column should, in no way, serve as a substitute for seeing a licensed medical practitioner.
The question above was submitted by @restdaysarebestdays. Please email [email protected] with your question for Ultra PT, Dave Cieslowski.