[1] Univ Gothenburg, Sahlgrenska Univ Hosp, Sahlgrenska Acad, Dept Orthopaed, S-43180 Gothenburg, Sweden
[2] Pittsburgh Med Ctr, Ctr Sports Med, Dept Orthpaed Surg, UPMC Rooney, 3200 S Water St, Pittsburgh, PA 15203 USA
[3] Kantonsspital Baselland Bruderholz LiestalLaufen, Dept Orthopaed Surg & Traumatol, CH-4101 Bruderholz, Switzerland