Musculoskeletal Simulation Based Optimization of Rehabilitation Program


Rehabilitation is a complex multifaceted process with complexity and variability that depends not only on human patients and/or specialized equipment but also on the nature of their functional interaction. Rapid and effective customization of the functional interactions between the patient and the rehabilitation device thus becomes critical for any rehabilitation program. Two principal dimensions govern the effectiveness of such functional interactions: geometric placement of user-device (ergonomics) and exercise selection and performance (regimen). In this paper, we discuss aspects of creation of a Virtual Design Environment, leveraging tools from musculoskeletal analysis, optimization, and simulation-based design, which will permit a therapist to rapidly evaluate and systematically customize various candidate rehabilitation programs. Specifically, this framework: (i) permits study of parametric performance variability due to ergonomic or regimen variability; and (ii) facilitates use of all design tools such as optimization to determine the best program. We illustrate various aspects of this customization using an illustrative case-study of a motor-rehabilitation haptic virtual driving environment.

In this work, we present the use of musculoskeletal analysis for designing an upper-limb exoskeleton.  Four different case studies are performed to study the effect of using a simplified exoskeleton on the muscle loading for arm curl with dumbbell. The simulation results showed that with the use of exoskeleton significant reductions in both, individual muscle forces and elbow flexion moment are achievable. The results also showed that the exoskeleton applied-torque synchronization with the required torque is important for the performance of the device. Prior approaches to exoskeleton designs used a more qualitative designer assessment to describe performance and/or fit. This engenders the usual limitations inherent to any semi- quantitative/qualitative design methodology including lack of invariances etc. In contrast, musculoskeletal analysis provide rational basis for biomechanically quantifying the performance of a candidate exoskeleton design and thus in turn provides a means for quantitatively comparing alternate designs. Nevertheless, the resulting copious amounts of raw quantitative data need to be further processed to extract useful metrics. Careful assessment of the quality, sensitivity and most importantly usability, of both the raw information and extracted metrics, is the focus of our current research.


 Students Involved:

- Leng-Feng Lee, Ph.D. Student.

- Madusudanan Narayan, Ph.D. Student.



 Movies :


1. Musculoskeletal Simulation based Optimization of Rehabilitation Program

- A video explain the idea, analysis, and results of this work.

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 Related Publications - Conference Proceedings:


Lee, L-F, Narayanan, M.S., Kannan, S., Mendel, F., Krovi, V.N. "Case Studies of Musculoskeletal-Simulation-Based Rehabilitation Program Evaluation", IEEE Transactions on Robotics, Vol. 25, No. 3, pp.634-638, June 2009.



Lee, L-F., and Krovi, V., “Musculoskeletal Simulation Based Optimization of Rehabilitation Programs,” Proceedings of the 2006 IEEE International Workshop on Virtual Rehabilitation, pp. 36-41, New York, NY, August 29 -30, 2006.


Sponsor: This project was funded by Research Foundation of State University of New York, National Science Foundation CAREER Award (IIS-0347653) and CNS-0751132.

Last Updated: August 28, 2010