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Heel Lifts - Anatomical Leg Length Discreppancy

Have you been told you need a heel lift? Have you been diagnosed with Scoliosis or a Leg Length Discrepancy? Have you been told your hips aren’t level, or one shoulder is higher than the other? Take a look at your arches. If one arch is significantly lower than the other, chances are that your feet are trying to compensate for a problem that could be related to your hips but can also be an Anatomical Leg Length Discrepancy.

Before you start wearing a heel lift in one shoe, let’s explore the root cause of what might be happening with your muscles and bones.
A difference in leg length causes pelvic instability. For people with an Anatomical Leg Length Discrepancy, the bones are uneven lengths, and this is most accurately documented by taking appropriate x-rays. Heel lifts are helpful when the ALLD is relatively small. If your ALLD is minimal, you can use our separately packaged Heel Lifts. They are made of polyurethane and measure 3mm each. They are sold in pairs, and are designed to be worn underneath the ProKinetics insole, in the bottom of the shoe, not next to the foot. You would start with ½ the discrepancy, building up to the full ALLD, but if it is over 1/4 - 3/8 inch the whole shoe should be built up from heel to toe.

Functional Leg Length Discrepancy (FLLD)   •   •   •   •   •   • 

When a practitioner has you lay down on the examining table and pulls your feet to see if your legs look the same length, this may confirm you have a difference in your leg lengths, BUT, the bones may be the same length. What is happening? This is very common for people who overpronate. The muscles on one side of your body are often stronger, or tighter than on the other. It may cause misalignments in the spine that can be adjusted, but once you stand up, you go out of adjustment again.

One foot oftentimes pronates more than the other. When this occurs, it performs as if it’s shorter than the other because the arch falls in and the knee moves inward more on one side than the other. This is more specifically diagnosed as a “Functional Leg Length Discrepancy”, and is muscle related not bone related because the body tries to compensate.

A good way to check if you may have a functional Leg Length Discrepancy is to test yourself for over pronation.

Up to two lifts can be placed in one shoe, compensating for a 1/4 in Anatomical Leg Length Discrepancy (ALLD).


Anatomical Leg Length Discrepancy (ALLD) should be established by x-ray to actually make direct measurements. Estimates by observation either standing or lying down is inaccurate and is more likely to reflect a Functional Leg Length Discrepancy (FLLD).