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Measuring Leg Length Discrepancy

Leg length discrepancyIf you consider that there is any possibility that you are suffering from a leg length discrepancy it's essential to assess the difference in leg length with very high accuracy. As you may know, leg length discrepancies can potentially cause a range of health problems including permanent spinal deformation and therefore by rectifying the problem through simple correction methods the chance of you suffering from these irreversible health problems is reduced considerably.

Clinical Methods

The most commonly use methods for measuring leg length discrepancy are the apparent and true leg length measurements as outlined below. Both of these methods require someone to help you in order to achieve the most accurate measurement.

True leg length measurements
This method involves measuring from the protuding pelvis bone, anterior superior illiac (see red points on the diagram below) to the ankle joint, medial malleoli. The use of a tailors tape measure is accepted. You should be able to easily feel the protruding bone on your pelvis, either at the front of back of your body. These points are a good point of reference for the measurement. With a tailor's type tape measure, simply measure from this bone to your ankle bone - it's best to do this whilst lying flat and have someone do it for you. By comparing the results for each leg the discrepancy can easily be found.

Apparent leg length measurement
This method is similar to the above, however it usually gives slight less accurate results. To measure a leg length discrepancy using this technique, measure from the belly button (umbilicus) to the ankle joint, medial malleoli.


methods of measuring leg length discrepancy


Scanogram method
Scanogram methodThis scanogram (or x-ray) is another method of measuring a leg length discrepancy, however it is clearly not available without profressional medical equipment. This methods involves scanning the pelvis and legs and with the use of computer technology, the images are enlarged to measure the distance between reference points (again, usually the pelvis and ankle joints), with very high accuracy.
This way of measuring is quite rare, as some physicians believe that the True and Apparent Leg Length Discrepancy methods as described above are accurate enough, as well as being quicker and cheaper to carry out.
Some health professionals stress that the more traditional methods of measuring such as the apparant and true methods (as above) are accurate enough without the need for a scan, which is expensive and time consuming and can even expose you to unnecessary radiation. It is therefore recommended that people try the easier and harmless methods first as clinical evidence suggests these are highly accurate when done carried out correctly and should suffice in the determination of your differences in leg length. Remember to ask someone to help you and always take more than one reading to find an average in case of any major errors.

I now know the discrepancy measurement, what next?

The most common solution to rectify the difference in your leg lengths is to compensate for the short fall in your shortest leg, thereby making both of your legs structurally the same length. Surgery is a drastic option and extremely rare, mainly because the results are not guaranteed aswell as the risks associated with surgery, not to mention the inconvenience of waiting until your broken bones are healed. Instead, orthopediatrician's will almost always advise on the use of "heel lifts for leg length discrepancy". These are a quick, simple and costs effective solution. They sit under your heel, inside your shoe and elevate your shorter leg by the same amount as the discrepancy. Most heel lifts are adjustable and come in a range of sizes. An example is shown below.

Such lifts can instantly correct a leg length discrepancy and prevent the cause of associate risks.

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