1. Department of Orthopaedic Surgery, Spine and Scoliosis Service, Hospital for Special Surgery, Weill Cornell Medical College, New York, New York, United States
2. 1st Orthopaedic Clinic, Cisanello Hospital, University of Pisa, Pisa, Italy
3. Department of Epidemiology and Biostatistics, Hospital for Special Surgery, Weill Cornell Medical College, New York, New York, United States