1. Orthopaedic and Injury Biomechanics Group, Departments of Orthopaedics and Mechanical Engineering, University of Pennsylvania, Philadelphia, Pennsylvania.
2. International Collaboration on Repair Discoveries, University of Pennsylvania, Philadelphia, Pennsylvania.
3. Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania.
4. Division of Spine, Department of Orthopaedics, University of British Columbia, British Columbia, Canada.