DOES IT REALLY MATTER IF YOUR LEGS ARE DIFFERENT LENGTHS?
By Christophe Champs, founder of PODO Clinic and Workshop
More than 50% of people have a difference in the lengths of their legs – it is known as limb length discrepancy. But for most people—whether they’re a one-leg-shorter or one-leg-longer type of person—the good news is that the difference is rarely very big and is usually only a few millimetres. A limb length discrepancy, or LLD, can also affect arms, but at PODO we specialise in all types of locomotion, including the gait, so let’s look specifically at leg length discrepancy.
Why do we have one leg shorter than the other?
An LLD can develop at any stage in life. It can be visible at birth (congenital) or acquired later while growing as a child and/or adolescent, or it can happen as an adult. An LLD can be post-traumatic, resulting from surgery or from a severe fracture affecting your thigh bone, tibia, fibula, foot or ankle. It can also be caused by a fracture that has poorly healed, an infection, a bone cyst, a bone tumour, and so on.
Our bodies always keep our eyes level on the horizon; from head to toe, every joint, at every level (ankle, knee, pelvis, shoulder, etc.) adapts in every body plane in order to ensure our eyes remain level. This sounds like an obviously good thing, but it can result in problems. For example, it can lead to an antalgic gait, where we walk differently to avoid discomfort, which manifests as a limp.
At that point, it is a good idea to see an expert in Biomechanics who can look at your gait and help you to avoid unnecessary body pain, now and in the future.
When it comes to biomechanics, focusing on your alignment, balance, and posture—both static and dynamic—allows us to measure the risks associated with a leg length discrepancy, in terms of direct damages or risks of developing osteoarthritis in the future.
However, be assured that an LLD is not a condition that automatically requires medical treatment. Sometimes it’s not even a problem.
What you do need to do if you have LLD is to start understanding why you have it, to notice how it impacts your quality of life, comfort, or performance and, most importantly, to find out how to deal with it.
Measuring a leg length discrepancy
A standing X-ray is the most common procedure to measure an LLD. However, this is also where I see the most inconsistency in results. Let’s be clear, X-rays are a phenomenal tool to help us assess our bones and joints, but they remain two-dimensional pictures trying to illustrate a three-dimensional reality.
For example, drop one of your arches by over-pronating (inward rolling) on one foot only, and your hip on the same side will probably drop as well – following your knee, of course. Structurally (in terms of bone size) you will be fine, but the drop of this arch would make that leg appear shorter. Now, if you imagine in this case that this postural short leg was diagnosed and addressed with a heel lift, not only will you not be helping your body to work better, but you might actually increase this overpronation and make things worse. In 2D it looks like a great idea to compensate for that frontal LLD – in reality, it is not.
Surgery or conservative treatments?
The main factors to take into consideration when addressing our fantastic human body are, firstly, the structural factors (bones’ lengths and shapes), and then the postural factors (positions and adaptations of bones and joints).
You will best address the postural problems with conservative treatments (non-surgical / non-invasive) or radical treatments (ones that aim to cure the disease rather than merely relieve symptoms). But you will only alter the structural factors by getting an orthopaedic surgeon onboard, to either lengthen the shorter leg or shorten the longer one. This is rarely necessary but sometimes it is. I cannot recommend enough getting opinions from two different consultants and making sure all conservative solutions have been tried and unsuccessful before going down this route.
Do NOT try to address an LLD alone. It is not always the source of your problems, it takes knowledge and skill to properly diagnose it, addressing it is a tricky task and, most importantly, the wrong solution will worsen the problem.
Heel lifts and wedges can be added as a conservative treatment, or a pair of orthotics or insoles within, or on, your shoes can be added straight away. Remember, they will only work when you wear them. This can be enough if you wear shoes a lot but becomes useless if you spend most of your time barefoot.
Keep an eye on your shoes, as they will wear unevenly, increase your asymmetry, affect your biomechanics and aggravate many symptoms.
Remember that it rarely matters whether you have one leg shorter/longer than the other. Up to a certain level of asymmetry or discomfort, we might not even address it with a heel lift or wedge.
ABOUT THE AUTHOR
Christophe Champs is an expert in Biomechanics and the founder of the PODO Clinic and Workshop. Christophe works with clients to help correct postural and biomechanical issues that are causing pain or putting a client at risk of injury. By testing both the moving gait and the still posture Christophe can correct misalignment and asymmetry by creating custom-made orthotics to suit the exact needs of each individual client.
This is not paid for or sponsored in any way.