1. From the Department of Radiology (C.S., J.G., R.S.), Sports Medical Research Group, Department of Orthopedics (S.F., L.P., J.S.), and University Centre for Prevention and Sports Medicine (S.F., L.P., J.S.), Balgrist University Hospital, Forchstrasse 340, CH-8008, Zürich, Switzerland; and Faculty of Medicine, University of Zurich, Zurich, Switzerland (C.S., J.G., R.S.).