1. University of New Mexico School of Medicine, Albuquerque, NM
2. Department of Orthopaedics, University of New Mexico School of Medicine, MSC 10 5600, Albuquerque, NM
3. Departamento de Aparelho Locomotor Universidade Federal de Minas Gerais Belo Horizonte, Brazil
4. Department of Orthopaedics,University of Cape Town
5. Clínica de Traumatología y Ortopedia, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay