1. Faculty of Dentistry McGill University Montreal Quebec Canada
2. The Alan Edwards Centre for Research on Pain McGill University Montreal Quebec Canada
3. Department of Orthopaedic Surgery, Graduate School of Medicine Chiba University Chiba Japan
4. Departments of Anesthesiology, Pharmacology and Therapeutics, Neurology and Neurosurgery, Faculty of Medicine McGill University Montreal Quebec Canada
5. Faculty of Medicine, Department of Anesthesiology University of Minnesota Minneapolis Minnesota USA