1. Department of Orthopaedic Surgery, Yokohama City University , Yokohama , Japan
2. Department of Orthopaedic Surgery, Yokohama City University Medical Center , Yokohama , Japan
3. Department of Diagnostic Pathology, Yokohama City University Hospital , Yokohama , Japan
4. Department of Molecular Pathology, Yokohama City University Graduate School of Medicine , Yokohama , Japan
5. Department of Diagnostic Pathology, Yokohama City University Medical Center , Yokohama , Japan