1. Department of Orthopedic Surgery, Joint Surgery, Sports Clinic Ishinomaki, Ishinomaki 986-0850, Japan
2. Department of Orthopaedic Surgery, Tohoku University School of Medicine, Sendai 980-8547, Japan
3. Department of Orthopedic Surgery, Iwaki Medical Center, Iwaki 973-8402, Japan
4. Division of Gastroenterology, Tohoku University School of Medicine, Sendai 980-8574, Japan