[1
]
Department of Orthopedics Surgery, Juntendo University, Hongo 2-1-1, Bunkyo-ku, Tokyo,
113-8421, Japan. si-onda@juntendo.ac.jp.
[2
]
Spine Center, Hakodate Central General Hospital, Hon-cho 33-2, Hakodate, Hokkaido,
040-8585, Japan.
[3
]
Department of Orthopedics Surgery, Juntendo University, Hongo 2-1-1, Bunkyo-ku, Tokyo,
113-8421, Japan.