A Model of the Lower Limb for Analysis of Human Movement


Computer models that estimate the force generation capacity of lower limb muscles have become widely used to simulate the effects of musculoskeletal surgeries and create dynamic simulations of movement. Previous lower limb models are based on severely limited data describing limb muscle architecture (i.e., muscle fiber lengths, pennation angles, and physiological cross-sectional areas). Here, we describe a new model of the lower limb based on data that quantifies the muscle architecture of 21 cadavers. The model includes geometric representations of the bones, kinematic descriptions of the joints, and Hill-type models of 44 muscle–tendon compartments. The model allows calculation of muscle–tendon lengths and moment arms over a wide range of body positions. The model also allows detailed examination of the force and moment generation capacities of muscles about the ankle, knee, and hip and is freely available at www.simtk.org.

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We thank Carolyn Eng, Trevor Kingsbury, Kristin Lieber, Jaqueline Braun, Laura Smallwood, and Taylor Winters and the Anatomical Services Department at the University of California San Diego for their work collecting this cadaver data. Funding for this work was provided by the National Institutes of Health Grants HD048501, HD050837, EB006735, U54 GM072970 and a Stanford Bio-X Graduate Student Fellowship.

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Correspondence to Scott L. Delp.

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Arnold, E.M., Ward, S.R., Lieber, R.L. et al. A Model of the Lower Limb for Analysis of Human Movement. Ann Biomed Eng 38, 269–279 (2010). https://doi.org/10.1007/s10439-009-9852-5

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  • Lower extremity
  • Hill-type model
  • Muscle architecture
  • Maximum isometric moment
  • Muscle strength