1. WM Glasoe, PT, ATC, is Staff Physical Therapist and Research Therapist, Physiotherapy Associates, 600 7th St SE, Cedar Rapids, IA 52401 (USA).
2. HJ Yack, PhD, PT, is Associate Professor, Physical Therapy Graduate Program, College of Medicine, The University of Iowa, Iowa City, Iowa
3. CL Saltzman, MD, is Associate Professor, Department of Orthopaedic Surgery and Biomedical Engineering, University of Iowa Hospitals and Clinics, Iowa City, Iowa