[1] Univ Tsukuba, Dept Orthopaed Surg, Fac Med, 1-1-1 Tennodai, Tsukuba, Ibaraki 3058575, Japan
[2] Univ Tsukuba Hosp, Dept Rehabil Med, Fac Med, 1-1-1 Tennodai, Tsukuba, Ibaraki 3058575, Japan
[3] Tsukuba Univ Hosp, Mito Clin Educ & Training Ctr, Dept Orthopaed Surg & Sports Med, 3-2-7 Miya Machi, Mito, Ibaraki 3100015, Japan
[4] Moriya Daiichi Gen Hosp, Dept Orthopaed Surg, 1-17 Matsumaedai, Ibaraki 3020102, Japan