1. Department of Orthopaedic Surgery; Graduate School of Medicine; Tohoku University; Sendai Japan
2. Tohoku Fukushi University; Sendai Japan
3. Department of Otrhopaedic Surgery; Takeda General Hospital; Aizuwakamatsu Japan
4. Division of Advanced Prosthetic Dentistry; Graduate School of Dentistry; Tohoku University; Sendai Japan