title: Identification of the Position and Thickness of the First Annular Pulley in Sonographic Images.
abstract: The purpose was to identify the A1 pulley's exact location and thickness by comparing measurements from a clinical high-frequency ultrasound scanner system (CHUS), a customized high-frequency ultrasound imaging research system (HURS) and a digital caliper. Ten cadaveric hands were used. We explored the pulley by layers, inserted guide pins and scanned it with the CHUS. After identifying the pulley, we measured each long finger's thickness using the CHUS and excised the pulley to measure its thickness with a digital caliper and the HURS. The thin hypo-echoic layer was revealed to be the synovial fluid space, and the pulley appears hyper-echoic regardless of scan direction. We also defined the pulley's boundaries. Moreover, the CHUS provided a significantly lower measurement of the pulley's thickness than the digital caliper and HURS. Likewise, based on the digital caliper's measurement, the HURS had significantly lower mean absolute and relative errors than the CHUS.
authors.affiliation: Department of Biomedical Engineering, National Cheng Kung University, Tainan, Taiwan; Orthopedic Biomechanics Laboratory, Division of Orthopedic Research, Mayo Clinic, Rochester, MN, USA; Department of Orthopedics, China Medical University Hospital, Taichung, Taiwan.
authors.forename: Tai-Hua
authors.initials: TH
authors.lastname: Yang
authors.affiliation: Department of Computer Science & Information Engineering, National Cheng Kung University, Tainan, Taiwan.
authors.forename: Yi-Hsun
authors.initials: YH
authors.lastname: Lin
authors.affiliation: Department of Computer Science & Information Engineering, National Cheng Kung University, Tainan, Taiwan.
authors.forename: Bo-I
authors.initials: BI
authors.lastname: Chuang
authors.affiliation: Department of Radiation Oncology, Washington University in Saint Louis, Saint Louis, MO, USA.
authors.forename: Hsin-Chen
authors.initials: HC
authors.lastname: Chen
authors.affiliation: Department of Biomedical Engineering, National Cheng Kung University, Tainan, Taiwan; Medical Device Innovation Center, National Cheng Kung University, Tainan, Taiwan.
authors.forename: Wei-Jr
authors.initials: WJ
authors.lastname: Lin
authors.affiliation: Department of Orthopedic Surgery, Ton-Yen General Hospital, Hsinchu, Taiwan.
authors.forename: Dee-Shan
authors.initials: DS
authors.lastname: Yang
authors.affiliation: Department of Computer Science & Information Engineering, National Cheng Kung University, Tainan, Taiwan; Medical Device Innovation Center, National Cheng Kung University, Tainan, Taiwan.
authors.forename: Shyh-Hau
authors.initials: SH
authors.lastname: Wang
authors.affiliation: Department of Computer Science & Information Engineering, National Cheng Kung University, Tainan, Taiwan; Medical Device Innovation Center, National Cheng Kung University, Tainan, Taiwan.
authors.forename: Yung-Nien
authors.initials: YN
authors.lastname: Sun
authors.affiliation: Department of Orthopedics, National Cheng Kung University, Tainan, Taiwan.
authors.forename: I-Ming
authors.initials: IM
authors.lastname: Jou
authors.affiliation: Department of Occupational Therapy, National Cheng Kung University, Tainan, Taiwan. Electronic address: jkkuo@mail.ncku.edu.tw.
authors.forename: Li-Chieh
authors.initials: LC
authors.lastname: Kuo
authors.affiliation: Department of Biomedical Engineering, National Cheng Kung University, Tainan, Taiwan; Medical Device Innovation Center, National Cheng Kung University, Tainan, Taiwan. Electronic address: fcsu@mail.ncku.edu.tw.
authors.forename: Fong-Chin
authors.initials: FC
authors.lastname: Su
mesh_terms: D059925:Anatomic Landmarks / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D002102:Cadaver; D005260:Female; D005384:Finger Joint / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008297:Male; D008875:Middle Aged; D010808:Physical Examination / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013624:Taiwan; D013710:Tendons / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D014463:Ultrasonography / Q000379:methods*
keywords: Flexor tendon pulley; High frequency ultrasound; Pulley thickness; Sonographic image; Trigger finger