Musculoskeletal Models

Oct 04, 2022

Just as interactive graphics have enhanced engineering analysis and design, graphics-based musculoskeletal models are effective tools for visualizing human movement, analyzing the functional capacity of muscles, and designing improved surgical procedures. The OpenSim team, along with researchers in the wider community, have created computer models of many different musculoskeletal structures. Learn more about these models below:

1 OpenSim Core Models
2 OpenSim Example Models
3 User-Contributed Models
4 SIMM Models

MODEL AUTHORS: Please feel free to update the model matrix with improved information. If you have an OpenSim model that you'd like to add to the list, please contact us at opensim@stanford.edu.

OpenSim Core Models

Models included with the OpenSim distribution and supported by the OpenSim team.

Model		Brief Description	Author(s)	Intended Uses and Known Limitations	License	Last Updated	Included Materials	Model Forerunners

Model	Brief Description	Author(s)	Intended Uses and Known Limitations	License	Last Updated	Included Materials	Model Forerunners
gait2392_simbody Get the Model: Included with OpenSim Learn More: Model Description	Primarily lower extremity model with two legs and a lumped torso segment. Includes 23 degrees of freedom and 92 muscle-tendon actuators.	Ajay Seth, Darryl Thelen, Frank C. Anderson, Scott L. Delp	Simulating and analyzing human movement that is dominated by lower extremity muscles. Results may be inaccurate during motions with high degrees of knee flexion. The model can be used for both kinematics and dynamics analyses.	Creative Commons CCBBY 3.0	Jul-13	Walking data, example set-up files	Delp Leg Model (SIMM)
gait2354_simbody Get the Model: Included with OpenSim Learn More: Model Description	Primarily lower extremity model with two legs and a lumped torso segment. Includes 23 degrees of freedom and 54 muscle-tendon actuators.	Ajay Seth, Darryl Thelen, Frank C. Anderson, Scott L. Delp	Simulating and analyzing human movement that is dominated by lower extremity muscles. The model can be used for both kinematics and dynamics analyses.Results may be inaccurate during motions with high degrees of knee flexion. The number of muscles in the model was reduced to speed simulation time for education and initial simulation prototyping. The model is used in Tutorial 3 - Scaling, Inverse Kinematics, and Inverse Dynamics	Creative Commons CCBBY 3.0	Jul-13	Walking data, example set-up files, reference simulation results	gait2392_simbody.osim
gait10dof18musc Get the Model: Included with OpenSim	Trunk, pelvis and leg segments. 10 degrees of freedom, 18 muscles	Ajay Seth, Darryl Thelen, Frank C. Anderson, Scott L. Delp	This model is a simplified model focused on the lower extremity. It demonstrates the use of the new Millard muscles in OpenSim. It is intended for education, demonstration, and for initial prototyping of simulations when fast simulation times are needed.	Creative Commons CCBBY 3.0	Jul-13	Walking data, example set-up files, reference simulation results	gait2392_simbody.osim
leg6dof9musc Get the Model: Included with OpenSim	Single leg, pelvis, femur, tibia, foot. 6 Degrees of Freedom, 9 muscles	Ajay Seth, Darryl Thelen, Frank C. Anderson, Scott L. Delp	This model is a simplified model focused on the lower extremity. It demonstrates the use of the new Millard muscles in OpenSim. It is intended for use in examples, including The Strength of Simulation: Estimating Leg Muscle Forces in Stance and Swing	Creative Commons CCBBY 3.0	Jul-13	Walking data, example set-up files, reference simulation results	gait2392_simbody.osim
ToyLandingModel Get the Model: Included with OpenSim	Trunk, pelvis leg and AFO segments. 23 degrees of freedom, 34 muscles. AFO model can be provide bushing forces and stiffness properties	Ajay Seth, Matt DeMars, John Rogers, Scott L. Delp	This model is intended for education and demonstrations. It shows how to define contact surfaces and define an AFO and controllers as part of a model. See Simulation-Based Design to Prevent Ankle Injuries	Creative Commons CCBBY 3.0	Jul-13	Example set-up files and detailed instructions	gait2354_simbody.osim
Arm26 Get the Model: Included with OpenSim	A right upper extremity model with 2 degrees of freedom and 6 muscles	Jeff Reinbolt, Ajay Seth, Sam Hamner, Ayman Habib	This is a simplified model of the extremity, intended primarily for education and demonstrations.	Creative Commons CCBBY 3.0	Jul-08	Movement data, instructions for use, and example scripts	Stanford VA Upper Limb Model
Tug_of_War Get the Model: Included with OpenSim	Simple model with two muscles pulling on a 1-dof block for a simulated tug of war. Models that implement both Thelen and Millard muscle types are provided	The OpenSim team	Simulation for students to explore differential equations that describe muscle activation and muscle–tendon contraction dynamics of Hill-type muscle model. See Pulling Out the Stops: Designing a Muscle for a Tug-of-War Competition	Creative Commons CCBBY 3.0	Jul-13	Movement data and example set-up files
wrist Get the Model: Included with OpenSim	A 10 degree of freedom, 23 muscle actuators, model of the lower arm.	Robert Gonzalez, Thomas Buchanan, Scott Delp	This is a simplified model of the wrist, intended primarily for education and demonstrations. See Tutorial 2 - Simulation and Analysis of a Tendon Transfer Surgery.	Creative Commons CCBBY 3.0	Jul-08	Movement data and instructions for use
bouncing_block Get the Model: Included with OpenSim	Simulation of a block with a 'leg' like spring attached.	Matt Demers	Simple model for education and demonstrations showing how to define contact and bushings.	Creative Commons CCBBY 3.0	Jul-13	Example set-up files

OpenSim Example Models

Additional models used in examples and tutorials not included with the OpenSim distribution. These models are also maintained by the OpenSim team at Stanford.

Model		Brief Description	Author(s)	Intended Uses and Known Limitations	License	Last Updated	Included Material	Model Forerunners

Model	Brief Description	Author(s)	Intended Uses and Known Limitations	License	Last Updated	Included Material	Model Forerunners
double_pendulum	A two body linkage system	Ajay Seth	Demonstrates how to analyze the trajectory of a point on a body. See Point Kinematics Example	Creative Commons CCBBY 3.0	Jul-13	Example set-up and motion files
Dynamic Walker Starter and Dynamic Walker Builder	Model of a basic dynamic walker	Daniel Jacobs	Demonstrates how to build a dynamic walker, add many OpenSim model components, and run a simulation via Matlab scripting. See Dynamic Walking Challenge: Go the Distance! and Depreciated_CPP_From the Ground Up: Building a Passive Dynamic Walker Model	Creative Commons CCBBY 3.0	Jul-13	Example data and model building scripts
Dynamic Jumper Model	Modified gait2354 model for jumping simulations	Daniel Jacobs, Jeff Reinbolt, B.J. Fregly, Clay Anderson, Allison Arnold, Silvia Blemker, Darryl Thelen, and Scott Delp	Used to demonstrate dynamic optimization with OpenSim. The example additionally analyzes the effects of excitation signals on performance. See Sky High: Coordinating Muscles for Optimal Jump Performance	Creative Commons CCBBY 3.0	Jul-13	Example controls and motion data	gait2354_simbody.osim
SeperateLegs	Two legs. 17 Degrees of freedom, 24 muscles	Scott L. Delp	This model was used in Tutorial 1 prior to OpenSim 3.2. As of OpenSim 3.2 it is no longer distributed and supported.	Creative Commons CCBBY 3.0	Jul-13	Walking data	Delp Leg Model (SIMM)
BothLegs	Trunk, pelvis and leg segments. 10 degrees of freedom, 18 muscles	Scott L. Delp	This model was used in Tutorial 1 prior to OpenSim 3.2. As of OpenSim 3.2 it is no longer distributed and supported.	Creative Commons CCBBY 3.0	Jul-13	Walking data	Delp Leg Model (SIMM)

User-Contributed Models

Models contributed by members of the OpenSim community. These models are developed and maintained by the authors listed, NOT the Stanford OpenSim team.

Model		Brief Description	Author(s)	Intended Uses and Known Limitations	License	Updated	Included Material	Model Forerunners

Model	Brief Description	Author(s)	Intended Uses and Known Limitations	License	Updated	Included Material	Model Forerunners
Upper Extremity Dynamic Model	A right upper extremity dynamic model representing the anthropometry and force-generating capacity of the 50th percentile male.	Katherine Saul, Xiao Hu, Craig Goehler Meghan Vidt, Melissa Daly, Anca Velisar, Wendy Murray	Research-grade kinematics and dynamic simulation of shoulder and arm movement.	MIT	July2014	Detailed description of the model, two versions of the model (OpenSim and SIMM/SDFast compatible)	Stanford VA Upper Limb Model
Lower limb model 2010 Learn More: Model Description	Lower limb model with updated musculoskeletal geometry for the lower limb based on experimental measurements of muscle architecture in 21 cadavers.	Edith Arnold, Richard Lieber, Scott Ward, Scott Delp	Research-grade kinematics analysis, and simulation of 3-D locomotion and other movements. Results may be inaccurate during motions with high degrees of knee flexion. The model can be used for dynamics analyses, but computation speed will be slow due to the large number of wrapping surfaces.	Custom	Sep-11	Detailed description of model and adequate instructions for use. Custom Matlab code for generating SIMM muscle model.	Arnoldetal2010_2Legsv2.1.osim, Arnoldetal2009OneLeg (SIMM) Delp leg Model (SIMM)
Full Body Running Model Learn More: Model Description	Legs, trunk and arm segments (with inertial properties). 37 degrees of freedom, 30 muscles of the lower body, torque actuated arms	Sam Hamner, Ajay Seth, Scott Delp	Research-grade kinematics analysis, dynamic analysis, and simulation of 3-D locomotion and other movements. Knee joint load estimates are known to be inaccurate during motions with high degrees of knee flexion. The upper body is simplified (minimal muscle actuation and torque-actuated arms).	Custom. See the model's Simtk project page.	Jul-10	Detailed description of model and detailed instructions for use.	gait2392_simbody.osim
Upper and Lower Body Model	Combination of the Delp Leg Model and Holzbaur Upper Limb Model	Andrea Menegolo	Provide a starting model to those interested in a full body model.	none	Sep-11	Model and brief description	Delp Leg Model, Stanford VA upper limb Model
London Lower Limb model	Unilateral lower limb model based on the data set published by Klein Horsman et al., Clin Biomech, 2007. Includes pelvis and right leg bodies (with inertia) and 38 muscles (represented as 163 muscle actuators)	Luca Modenese, Andrew Phillips	Lower limb model implemented to estimate the contact forces occurring at the hip joint during activities of daily living. The model can be used for static optimization simulations without including the muscle force-length-velocity relation.	Creative Commons CCBBY 3.0	Jul-11	Description and adequate instructional material.
Custom Hip Model	Model based on Gait2392, Lower and trunk bodies (with inertia), updated muscle parameters matching previously published research.	Kevin Shelburne	Research on motion and muscle function at the hip joint. Can be used for dynamics analysis	Creative Commons CCBBY 3.0	Aug-10	Instructional material	Gait2392_simbody
Thoracolumbar spine and rib cage.	Male and female versions of fully articulated thoracolumbar spine (T1 through L5) and rib cage, plus pelvis, lumped head and neck, and upper extremities, includes 93 degrees of freedom, and 552 muscle-tendon actuators.	Alexander Bruno, Dennis Anderson, Mary Bouxsein, Hossein Mokhtarzadeh, Katelyn Burkhart.	The model is validated for determining estimations of spine loading and muscle activations via Static Optimization.	MIT	July-2017	Models, geometry files, example motion file, description of differences between male and female models.	Lumbar Spine Model, Neck Mechanics Model, Stanford VA upper limb model
Lumbar Spine Model	Lumbar bodies and torso containing 3Dof and 238 muscle fascicles.	Miguel Christophy, Nur Adila Faruk Senan, Moe Curtin	Research-grade kinematics analysis, and simulation. Due to no inertial properties for the bodies, this model is inappropriate for dynamics analysis. Only LumbarSpineC4 is usable in OpenSim 3.1.	Creative Commons CCBBY 3.0	Nov-10	Geometry, examples, editing instructions and Matlab code.	LumbarSpineC210, LumbarSpineC4
Rat Hindlimb Model	A rat hindlimb musculoskeletal model including geometry (with interia) and muscle physiology.	Will Johnson	Research on Rat musculoskeletal kinematics and muscle function	Commons CCBBY 3.0	Jan-09
Chimpanzee Hindlimb	A unilateral three dimensional musculoskeletal model of the chimpanzee pelvis and hind limb.	Brian Umberger, Mathew O'Neill, Leng-Feng Lee	Model used to estimate the force- and moment-generating capacity of the major pelvis and hind limb muscles in the chimpanzee.	MIT license	Nov- 13	Model, Geometry files.
Full Upper and Lower Body Model	A refined human musculoskeletal model suitable for analysing movements involving substantial hip and knee flexion such as cycling, sprinting and rowing.	Adrian Lai, Allison Arnold, James Wakeling	The model was generated when we encountered anomalous co-activation in the hip and knee flexors during muscle-driven simulations of pedaling due primarily to excessive passive fibre forces in the extensor muscles.	MIT license	Oct-17	Three models (lower limb only, torso, torso + arms), Geometry files	Rajagopal2015
Oculomotor Model	A biomechanical model of the human eye containing 3 degrees-of-freedom and 6 muscles. The muscle activation patterns of saccadic movements are calculated using a closed-loop fixation controller.	Konstantinos Filip, Dimitar Stanev, Konstantinos Moustakas	Research-grade kinematics and dynamics analysis, investigation of muscle activation patterns during saccadic movements and static fixation, simulation of eye disorders. The model is based only on the passive and not the active pulley hypothesis.	Creative Commons CC BY 4.0	Apr-20	Models, geometry and texture files, detailed documentation, plugin release of the fixation controller, source code, simulation results.
Kinematic Arm Model with Articulated Hand	A right upper extremity kinematic model adapted from the “Upper Extremity Dynamic Model” with 20 degrees of freedom added to the hand. The model is scaled to a 50^th percentile human being.	Matthew Yough, Russell Hardesty, Matthew Boots, Sergiy Yakovenko, Valeriya Gritsenko	Research-grade kinematics of shoulder, arm, and hand movement. The model contains no muscles.	None	Oct-21	Model, geometry files, and description of the model and its uses.	Saul et al. 2015: Upper Extremity Dynamic Model

SIMM Models

Models contributed by members of the SIMM community as SimTK projects. These models are maintained by the authors listed.

Model(s) name

Model(s) name

OpenSim is supported by the Mobilize Center , an NIH Biomedical Technology Resource Center (grant P41 EB027060); the Restore Center , an NIH-funded Medical Rehabilitation Research Resource Network Center (grant P2C HD101913); and the Wu Tsai Human Performance Alliance through the Joe and Clara Tsai Foundation. See the People page for a list of the many people who have contributed to the OpenSim project over the years. ©2010-2024 OpenSim. All rights reserved.