1. 1Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana, USA; email: chand@purdue.edu
2. 2School of Mechanical Engineering, Purdue University, West Lafayette, Indiana, USA
3. 3Department of Orthopaedic Surgery, Washington University in St. Louis, St. Louis, Missouri, USA
4. 4Shriners Hospitals for Children–St. Louis, St. Louis, Missouri, USA
5. 5Shu Chien-Gene Lay Department of Bioengineering, University of California San Diego, La Jolla, California, USA
6. 6Paul M. Rady Department of Mechanical Engineering, University of Colorado Boulder, Boulder, Colorado, USA