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This project holds all the files necessary for a SIMM-based musculoskeletal model of deformable human femur that can be used to easily model rotational deformities. In order to respect the time and effort put in by the original developers please carefully read accompanying publications and cite appropriate references in future work. The links to the left contain all the files (Downloads) and documentation (Documents) related to the model.

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Please cite the following paper:
- Arnold and Delp. Rotational moment arms of the hamstrings and adductors vary with femoral geometry and limb position: implications for the treatment of internally-rotated gait. Journal of Biomechanics, 2001.

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About the model:
Originally developed by Scott Delp and Alison Arnold to examine the effects of bony deformities of the femur, this model characterizes the geometry of the pelvis, femur, and proximal tibia, the kinematics of the hip and tibiofemoral joints, and the paths of the medial hamstrings, iliopsoas, and adductor muscles for an average-sized adult male. The femur of the model can be altered to represent anteversion angles of 0-60°, neck-shaft angles of 110-150°, and/or neck lengths of 35-60 mm. The lesser trochanter torsion angle of the model can be adjusted by as much as 30° anteriorly or 10° posteriorly. Hence, this model enables rapid and accurate estimation of muscle-tendon lengths and moment arms for individuals with a wide range of movement abnormalities and femoral deformities.

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