1. Department of Orthopaedic Surgery; Tohoku University School of Medicine; Sendai 980-8574 Japan
2. Division of Craniofacial Function Engineering; Tohoku University Graduate School of Dentistry; Sendai 980-8575 Japan
3. Tohoku Orthopaedic Clinic; Sendai 981-3121 Japan
4. Department of Orthopedic Surgery; Osaki Citizen Hospital; Osaki 989-6183 Japan