Having a difference in the length of your legs causes your body to work harder to clear the ground when walking, which can lead to pain and problems.
Also known as a limb length discrepancy, a leg length difference describes a physical difference in the length between a person’s legs when two anatomical points are measured. While it’s not surprising that many people have a small difference given that our bodies are not perfectly symmetrical, significant differences in length have the potential to cause pain and other problems not just at the legs but the hips and back, affecting a person’s daily comfort, movement and their quality of life.
Having a leg length difference can create a tilt at the hips and various joints in the feet and legs, and may even adversely affect your spine too. It can result in other joints and structures being overloaded, stressed, stretched and restricted in their function. This can present in a variety of symptoms, from a limping gait to shorter steps and walking speed, to overuse injuries, stress fractures - and hip, knee and back pain. As such, the signs of a leg length difference can include everything from:
In order to understand the cause of a leg length difference, we need to understand the two types of length differences you can have: structural and functional.
A structural leg length difference is measured when a person is not bearing any weight on their feet, such as when they’re laying down. Finding a difference in the structural length reflects directly on there being a difference in the length of the femurs (thigh bones) or tibias (shin bones). This difference may well be a natural difference you were born with, or could be related to a previous injury, disease, or a byproduct of a former surgery like a knee replacement.
A functional difference is measured when a person is standing and bearing weight on their feet - hence when their feet and legs are “functional”. Those with a functional leg length difference may have the same structural leg length when anatomical measurements are taken laying down, but due to the way the muscles, bones, connective tissues and joints work together when standing or walking, a leg length difference is created. We often see functional differences linked to tight, contracted muscles, such as at the hips. We also see it when ligament laxity or tendon dysfunction affects one foot more than the other. Neurological diseases are another common cause for functional differences. A common example is when posterior tibial tendon dysfunction causes one foot to become flatter than the opposite foot. The hip and knee of the flatter foot are more likely to be sitting lower to the ground than that of the other leg, creating a leg length difference.
Simply having a leg length difference, especially a small one, doesn’t necessarily warrant treatment - especially if it is from a natural length variation that you’ve had for decades and hasn’t bothered you. Studies have shown that up to 90% of people will have a 5mm difference, and many will remain asymptomatic. If a leg length difference is paired with pain or other symptoms, however, this does warrant further investigation and treatment. In this case, at home, you may try:
Here at Matt Raden Podiatry, our trusted and experienced podiatrists listen to the concerns, goals and needs of our patients with leg length differences, and utilise a range of evidence-based treatment methods to help you get the best outcome.
Every appointment starts with a comprehensive assessment to measure a suspected leg length difference, determine whether it is structural or functional in nature, and understand the impact that it is having on the biomechanics of your ankles, feet and legs. We’ll then create a tailored treatment plan based on your results that focuses on bringing the legs into greater balance and alignment. To achieve this, we may use:
If you’re concerned about a leg length difference, our team is here to help - and to ensure you have the best experience doing so. We’re proud to go above and beyond for our patients, focusing not only on managing your pain and symptoms, but helping you get the best long-term outcomes.