[1] Wakayama Med Univ, Dept Orthopaed Surg, Wakayama 6410012, Japan
[2] Keio Univ, Dept Orthopaed Surg, Tokyo, Japan
[3] Kawasaki Med Coll, Dept Orthopaed Surg, Okayama, Japan
[4] Hokkaido Univ, Dept Orthopaed Surg, Sapporo, Hokkaido, Japan
[5] Tohoku Univ, Dept Orthopaed Surg, Sendai, Miyagi 980, Japan
[6] Fukushima Med Univ, Dept Orthopaed Surg, Fukushima, Japan
[7] Chiba Rosai Hosp, Dept Orthopaed Surg, Chiba, Japan
[8] Chigasaki Tokushukai Med Ctr, Dept Orthopaed Surg, Kanagawa, Japan
[9] Hachiya Orthopaed Hosp, Dept Orthopaed Surg, Aichi, Japan
[10] Osaka City Univ, Dept Orthopaed Surg, Osaka 558, Japan
[11] Takamatsu Red Cross Hosp, Dept Orthopaed Surg, Takamatsu, Kagawa, Japan
[12] Kurume Univ, Dept Orthopaed Surg, Fukuoka, Japan
[13] Teikyo Univ, Mizonokuchi Hosp, Dept Orthopaed Surg, Tokyo 173, Japan
[14] Tokyo Med & Dent Univ, Dept Orthopaed Surg, Tokyo, Japan
[15] Gifu Univ, Dept Orthopaed Surg, Gifu, Japan