The Limb Symmetry Index (LSI) provides you with useful information about your leg strength, by using the simple math equation after completing your thigh girth measurements: circumference of the injured leg divided by the circumference of the uninjured leg times 100

For more information on thigh girth measurements and the LSI check out our blog here.

Check out our blog with a video about thigh girth measurements here and a step-by-step video on how to complete the measurement here.

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1. ARC Seminars LLC. ARC Seminars: Lower Extremity Girth Measurement [Video]. YouTube. Published January 10, 2018. Accessed September 13, 2022.

2. Lee JH, Cheon S, Jun HP, Huang YL, & Chang E. Bilateral Comparisons of Quadriceps Thickness after Anterior Cruciate Ligament Reconstruction. Medicina. 2020;56(7):335.

3. Konrath GA, Chen D, Lock T, et al. Outcomes Following Repair of Quadriceps Tendon Ruptures. Journal of Orthopaedic Trauma. 1998;12(4):273-279.

4. Soderberg GL, Ballantyne BT, & Kestel LL. Reliability of lower extremity girth measurements after anterior cruciate ligament reconstruction. Physiotherapy Research International. 1996;1(1):7-16.

5. Perry BD, Levinger P, Morris HG, et al. The effects of knee injury on skeletal muscle function, Na+, K+-ATPase content, and isoform abundance. Physiological reports. 2015;3(2):e12294.

6. Chan DK, Lonsdale C, Ho PY, Yung PS, & Chan KM. Patient motivation and adherence to postsurgery rehabilitation exercise recommendations: the influence of physiotherapists' autonomy-supportive behaviors. Archives of physical medicine and rehabilitation. 2009;90(12):1977-1982.

7. Drzezo. Measurement in rehabilitation. Musculoskeletal Key. Published April 13, 2019. Accessed September 13, 2022.

8. Kuenze C, & Kelly A. Quadriceps symmetry after ACL reconstruction. Lower Extremity Review. Published December 21, 2015. Accessed September 13, 2022.