1. Department of Orthopaedics, University of New Mexico Health Sciences University, ACC-2 West Albuquerque, New Mexico 87120, USA.
2. Emanuel Hospital and Health Center, 501 North Graham Street, Suite 200, Portland, Oregon 97227, USA.
3. Division of Orthopaedics and Rehabilitation, Oregon Health Sciences University, 3181 South West Sam Jackson Park Road, L477 Portland, Oregon 97201-3098, USA.