Leg length discrepancy (LLD) is a condition in which a pair of lower extremity limbs have a noticeably unequal length.
Leg length discrepancy (LLD) is a condition in which a pair of lower extremity limbs have a noticeably unequal length. This almost always occur as a result of shortening of the leg. This condition is extraordinarily common, however the clinical significance is a matter of debate.
The diagnosis is primarily clinical and can be confirmed by full length leg radiographs. It is a widely accepted clinical condition, however there is little consensus regarding treatment. Controversy among researchers and clinicians includes extent to clinical significance, prevalence, accuracy of measurement, effect of LLD on function, role in numerous MSK conditions Illustration of some of the compensatory changes.The causes of LLD can loosely be broken down into congenital and acquired.
Examples of acquired LLD include primary due to loss of bone and secondary due to trauma, infection in skeletally immature patients and paralysis from conditions like cerebral palsy or polio. Congenital causes may be considered idiopathic without always a clear cause however examples include hemihypertrophy, dysplasias, developmental dysplasia of the hip and unilateral clubfoot. Left: Double-leg stance with equal weight distribution in the presence of leg length discrepancy.
"Leg length discrepancy—treatment indications and strategies." Deutsches Ärzteblatt International 117.24: 405.[/ref]There is also a functional form that can be used to describe leg length discrepancy. In these patients, the unilateral asymmetry of the lower extremity occurs without any shortening of the osseous components. Functional causes include shortening of the soft tissues, joint contractures, ligamentous laxity, axial malalignments and abnormal foot biomechanics.
This can only be detected clinically and radiographs are typically normal. The LLD can develop as abnormal motion of the hip, knee, ankle or foot in any plane of motion Structural (Anatomical) and Functional Causes of Leg Length Discrepancy (click to enlarge)Compensatory structural changes can occur.
If you are experiencing symptoms that may be related to leg length discrepancy, it is important to see a sports medicine physician. Early evaluation and treatment typically lead to better outcomes. Do not ignore pain or symptoms that are limiting your activity.
*This article is for educational purposes only and does not substitute for professional medical advice. Always consult a qualified healthcare provider.*
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