1. American Hip Institute Research Foundation, 999 E Touhy Ave Ste 450, Des Plaines, IL 60018, USA
2. American Hip Institute, 999 E Touhy Ave Ste 450, Des Plaines, IL 60018, USA
3. Des Moines University, Desert Orthopaedic Center, 2800 E, Desert Inn Rd, Las Vegas, NV 89121, USA
4. Centro Medico Decente La Trinidad (Trinity Medical Center), Av. Principal de El Hatillo, Caracas 1080, Metropolitan District of Caracas, Venezuela
5. Atlantis Orthopaedics, 4560 Lantana Rd Suite 100, Lake Worth, Atlantis, FL 33463, USA
6. Footbridge Centre for Integrated Orthopaedic Care, 181 Keefer Pl #221, Vancouver, BC V6B 6C1, Canada
7. Croydon University Hospital, 530 London Rd, Thornton Heath CR7 7YE, London, UK
8. Hospital Distrital de Santarém, Av. Bernardo Santareno 3737B, 2005-177 Santarém, Portugal
9. Hospital Clinica Mompia, Av. de los Condes, s/n, 39108 Mompía, Cantabria, Spain
10. University Hospital Infanta Leonor, Av. Gran Vía del Este, 80, 28031 Madrid, Spain and
11. Warwick Medical School, University of Warwick and University Hospitals of Coventry and Warwickshire, Coventry CV4 7AL, UK