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Methods for Assessing Leg Length Discrepancy

Clinical Orthopaedics and Related Research volume 466, pages 2910–2922 (2008)Cite this article

Abstract

The use of accurate and reliable clinical and imaging modalities for quantifying leg-length discrepancy (LLD) is vital for planning appropriate treatment. While there are several methods for assessing LLD, we questioned how these compared. We therefore evaluated the reliability and accuracy of the different methods and explored the advantages and limitations of each method. Based on a systematic literature search, we identified 42 articles dealing with various assessment tools for measuring LLD. Clinical methods such as use of a tape measure and standing blocks were noted as useful screening tools, but not as accurate as imaging modalities. While several studies noted that the scanogram provided reliable measurements with minimal magnification, a full-length standing AP computed radiograph (teleoroentgenogram) is a more comprehensive assessment technique, with similar costs at less radiation exposure. We recommend use of a CT scanogram, especially the lateral scout view in patients with flexion deformities at the knee. Newer modalities such as MRI are promising but need further investigation before being routinely employed for assessment of LLD.

Level of Evidence: Level IV, diagnostic study. See the Guidelines for Authors for a complete description of levels of evidence.

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Acknowledgments

We thank Dr. Caixia Zhao and Ms. Emily McClemens, PA-C, for their assistance in preparing this manuscript.

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Authors and Affiliations

  1. Division of Pediatric Orthopaedics, Department of Orthopaedics, UMDNJ—New Jersey Medical School, Newark, NJ, USA

    Sanjeev Sabharwal MD & Ajay Kumar MD

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  1. Sanjeev Sabharwal MD
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  2. Ajay Kumar MD
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Correspondence to Sanjeev Sabharwal MD.

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Each author certifies that he or she has no commercial associations (eg, consultancies, stock ownership, equity interest, patent/licensing arrangements, etc) that might pose a conflict of interest in connection with the submitted article.

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Sabharwal, S., Kumar, A. Methods for Assessing Leg Length Discrepancy. Clin Orthop Relat Res 466, 2910–2922 (2008). https://doi.org/10.1007/s11999-008-0524-9

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  • DOI: https://doi.org/10.1007/s11999-008-0524-9

Keywords

  • Intraclass Correlation Coefficient
  • Compute Radiography
  • Anterior Superior Iliac Spine
  • Medial Malleolus
  • Angular Deformity