[1] Int Univ Hlth & Welf IUHW, Sch Med, Dept Orthopaed Surg, Chiba 2868686, Japan
[2] Int Univ Hlth & Welf IUHW, Dept Orthopaed Surg, Spine & Spinal Cord Ctr, Mita Hosp, Tokyo 1088329, Japan
[3] Int Univ Hlth & Welf IUHW, Dept Orthopaed Surg, Mita Hosp, Chiba 2868520, Japan
[4] Sapporo Spine Clin, Sapporo, Hokkaido 0600042, Japan
[5] Aomori Prefectural Cent Hosp, Dept Orthopaed Surg, Aomori 0308553, Japan
[6] Fukushima Med Univ, Dept Orthopaed Surg, Sch Med, Fukushima 9601295, Japan
[7] Kitasato Univ, Dept Orthopaed Surg, Kitasato Inst Hosp, Tokyo 1088642, Japan
[8] Jikei Univ, Dept Orthopaed Surg, Sch Med, Tokyo 1058471, Japan
[9] Takaoka City Hosp, Dept Orthopaed Surg, Takaoka, Toyama 9338550, Japan
[10] Kansai Med Univ, Dept Orthopaed Surg, Osaka 5731191, Japan
[11] Kawasaki Med Sch, Dept Orthopaed Traumatol & Spine Surg, Okayama 7010192, Japan
[12] Saga Univ, Dept Orthopaed Surg, Sch Med, Saga 8498501, Japan
[13] Okayama Rosai Hosp, Dept Orthopaed Surg, Okayama 7028055, Japan
[14] Kansai Med Univ, Dept Orthopaed Surg, Med Ctr, Osaka 5731010, Japan
[15] Kyushu Cent Hosp, Dept Orthopaed Surg, Fukuoka 8150032, Japan
[16] Tokyo Spine Ctr, Dept Orthopaed Surg, Sonoda Med Inst, Tokyo 1210807, Japan
[17] Nagoya Daini Hosp, Dept Orthopaed Surg, Japanese Red Cross Aichi Med Ctr, Nagoya, Aichi 4668650, Japan