1. Department of Dental Medicine , Karolinska Institute , Huddinge , Sweden
2. Pain Center , Academic Hospital of Uppsala , Uppsala , Sweden
3. Falu lasarett , Falun , Sweden
4. Physiotherapy Department and Pain Clinic , Karolinska University Hospital , Stockholm , Sweden
5. Fysiocenter , Odenplan , Stockholm , Sweden
6. Pain Center, Department of Anesthesia and Intensive Care , Akademiska sjukhuset , Uppsala , Sweden