[1] Niigata Univ, Grad Sch Med & Dent Sci, Dept Regenerat & Transplant Med, Div Orthoped Surg, 1-757 Asahimachi Dori,Chuo Ku, Niigata, Niigata 9518510, Japan
[2] Niigata Univ, Med & Dent Hosp, Uonuma Inst Community Med, Dept Orthoped Surg, Minami Uonuma, Niigata, Japan
[3] Niigata Rosai Hosp, Dept Orthoped Surg, Joetsu, Niigata, Japan
[4] Kameda Daiichi Hosp, Niigata Spine Ctr, Niigata, Niigata, Japan
[5] Univ Niigata Prefecture, Fac Human Life Studies, Dept Hlth & Nutr, Niigata, Niigata, Japan