1. Physical Medicine and Rehabilitation Department, Northwestern University, Chicago, IL, USA
2. Mechanical Engineering department, Australian College of Kuwait, Kuwait City, Kuwait
3. Department of Mechanical Engineering, University of Louisiana at Lafayette, Lafayette, LA, USA
4. Department of Physical Medicine and Rehabilitation, University of Texas Southwest, Dallas, TX, USA
5. Department of Orthopedic Surgery, University of Texas Southwest, Dallas, TX, USA
6. Bioengineering, University of Texas Southwest, Dallas, TX, USA