1. Department of Orthopedics Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine Shanghai Jiao Tong University Shanghai 200233 P. R. China
2. Department of Ultrasound in Medicine Shanghai Institute of Ultrasound in Medicine Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine Shanghai Jiao Tong University Shanghai 200233 P. R. China
3. Department of Gynecology Obstetrics and Gynecology Hospital of Fudan University Fudan University Shanghai 200090 P. R. China
4. Department of Clinical Laboratory Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine Shanghai Jiao Tong University Shanghai 200233 P. R. China