1. European League Against Pain, Zurich and Rome, Switzerland and Italy;
2. Analgesics and Pain Research Unit (APRU), King’s College Hospital, London, UK;
3. 4th Orthopaedic Department, KAT Hospital, Athens, Greece;
4. Anaesthesiology & Surgery Department, Hospital Arnau de Vilanova, Lleida, Spain;
5. Anaesthesiology Department, Hospitales Mar-Eseranza, Barcelona, Spain; ;
6. Universitat Autonoma de Barcelona;
7. Department of Anaesthesiology and Intensive Care, Jena University Hospital, Jena, Germany;
8. Centre de la Douleur, Université Paris Descartes, INSERM U987, Hopital Cochin, Paris, France;
9. Clinical Pharmacology & Digestive Pathophysiology Unit, Department of Clinical & Experimental Pharmacology, University of Parma, Parma, Italy