1. Department of Orthopedic Surgery; Nara Medical University; Kashihara Nara Prefecture 634-8522 Japan
2. Department of Physical Therapy; Osaka Yukioka College of Health Science; Osaka Japan
3. Department of Orthopedics; Osaka University School of Medicine; Osaka Japan
4. Department of Orthopedics; Sapporo Daiichi Hospital; Sapporo Japan
5. Department of Orthopedics; Sapporo Medical University; Sapporo Japan
6. Department of Anatomy; Sapporo Medical University; Sapporo Japan