1. a Department of Mechanical Engineering, University of Louisville, Room 200 Sackett Hall, Louisville, KY 40292, USA
2. b Division of Physical Therapy, Ohio State University, 1583 Perry Street, Columbus, OH 43210, USA
3. c Systems Analysis and Engineering Department, Battelle Memorial Institute, 505 King Avenue, Columbus, OH 43201, USA
4. d Division of Orthopaedics, Ohio State University, 410 West Ninth Avenue, Columbus, OH 43210, USA