1. Department of Pediatric Orthopaedics, Sanatorio Allende, Córdoba, Argentina
2. Hospital Roberto del Río
3. Clínica Alemana, Santiago
4. Universidad Austral de Chile, Valdivia, Chile
5. Hospital del Trabalhador, Curitiba, Brazil
6. Division of Orthopaedic Surgery, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA