[1] Univ Med Ctr, Dept Pathol, Leiden, Netherlands
[2] Univ Oxford, Oxford, England
[3] Olga Hosp, Stuttgart, Germany
[4] Osped Civile, Treviso, Italy
[5] Ist Ortoped Rizzoli, Bologna, Italy
[6] Royal Orthopaed Hosp, Birmingham B31 2AP, W Midlands, England
[7] Norwegian Radium Hosp, Oslo, Norway
[8] Weatherall Inst Mol Med, Oxford, England
[9] Univ Klinikum, Munster, Germany
[10] Univ Childrens Hosp Basel, Basel, Switzerland
[11] Univ Coll London Hosp, London, England