Many patients whom we examine for conditions such as lower back pain, knee pain or hip pain find out for the first time after their initial examination that their issues stem from a discrepancy in their leg length. A leg length discrepancy occurs when one leg is longer than the other. This isn’t as rare as you may expect. Discrepancies of up to 5 or about 2 inches are regularly seen in patient’s whom before their examination are completely unaware that this exists.
Our true leg length is measured from the anterior superior iliac spine (ASIS) (a bony prominence just above the hip joint on each leg) to the medial malleolus (the bone on the inside of the ankle joint). Each side is compared to assess for differences. Apparent leg length is then measured from the umbilicus (belly button) to the same point on each ankle. This allows us to assess what compensatory techniques are being used by patients to account for true leg length discrepancies.
Leg length discrepancy is only significant when it’s associated with symptoms such as lower back pain, knee pain or hip pain. If identified in individuals with no symptoms it can be left untreated. Where symptoms arise, it may be an underlying cause of the condition and various techniques such as stretching, heel lifts, strengthening exercises may be employed to remedy the discrepancy.