Affiliation: | 1.Department of Orthopedics, University Medical Center Groningen, University of Groningen, P.O. Box 30.001, 9700 RB, Groningen, The Netherlands ;2.Department of Health Sciences, Community and Occupational Medicine, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands ;3.Department of Orthopedics, R?pcke-Zweers Hospital Hardenberg, Hardenberg, The Netherlands ;4.Department of Orthopedics, Medical Center Leeuwarden, Leeuwarden, The Netherlands ;5.Department of Orthopedics, Martini Hospital Groningen, Groningen, The Netherlands ; |