A limb length discrepancy is a difference in the length of the limbs. In the lower extremity it is referred to as a Leg Length Discrepancy. There are three categories of leg length discrepancy; structural, functional and environmental. All three categories can result in pain in the foot, ankle, knee, hip and back.
Structural leg length discrepancies are a true shortening of the bones of one leg. Structural leg length discrepancy has many causes and include; congenital, infection or injury to a child’s bone, and trauma or surgery to a mature bone or joint resulting in a shortened position. Structural leg length discrepancies can be treated with a Scott Heel Lift to balance the discrepancy. Up to a 1cm lift can be put in a shoe if needed.
In a functional leg length discrepancy one leg appears shorter but there actually is no difference in the length of the bones. Function leg length discrepancy can be caused by positional deformities of the foot such as excessive pronation. Functional leg length discrepancies due to excessive pronation of the foot are treated with functional orthotics like those made by Ortho-Dynamics.
Environmental leg length discrepancies are a result of an external cause. Running or walking on a banked track will cause an unequal leg length. Treatment in this case is simply to change the environment in which you exercise. The use of a walking boot after an injury of surgery will also cause an environmental leg length discrepancy. Treatment in this case is to use a Scott Heel Lift on the uninjured leg to balance the discrepancy.