title: Reliability of automatic vibratory equipment for ultrasonic strain measurement of the median nerve.
abstract: The objective of this study was to test the reliability of ultrasonic median nerve strain measurements using automatic vibratory equipment. Strain ratios of the median nerve in the carpal tunnel model and the reference coupler were measured at three different settings of the transducer: 0, +2 and +4 mm (+ = compressing the model down 2-4 mm initially). After measurement of the carpal tunnel model, a +4-mm setting was chosen for in vivo measurement. The median nerve strains of 30 wrists were measured by two examiners using the equipment. Intra- and inter-examiner correlation coefficients (CCs) for the strain ratios were calculated. The closest ratio was found in the +4-mm placement (strain ratio: 0.73, Young's modulus ratio: 0.79). The intra-examiner CC was 0.91 (p < 0.01), and the inter-examiner CCs were 0.72-0.78 (p < 0.01). The automatic vibratory equipment was useful in quantifying median nerve strain at the wrist.
authors.affiliation: Department of Orthopaedic Surgery, Endowed Department of Human Resources Development for Community Medicine, Tokyo Medical University Ibaraki Medical Center, Ami, Japan. Electronic address: yy12721@yahoo.co.jp.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Yoshii
authors.affiliation: Department of Orthopaedic Surgery, Endowed Department of Human Resources Development for Community Medicine, Tokyo Medical University Ibaraki Medical Center, Ami, Japan.
authors.forename: Tomoo
authors.initials: T
authors.lastname: Ishii
authors.affiliation: Department of Orthopaedic Surgery, Endowed Department of Human Resources Development for Community Medicine, Tokyo Medical University Ibaraki Medical Center, Ami, Japan.
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Etou
authors.affiliation: Department of Orthopaedic Surgery, Endowed Department of Human Resources Development for Community Medicine, Tokyo Medical University Ibaraki Medical Center, Ami, Japan.
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Sakai
authors.affiliation: Department of Orthopaedic Surgery, Kikkoman General Hospital, Noda, Japan.
authors.forename: Toshikazu
authors.initials: T
authors.lastname: Tanaka
authors.affiliation: Department of Orthopaedic Surgery, Kikkoman General Hospital, Noda, Japan.
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Ochiai
mesh_terms: D002349:Carpal Tunnel Syndrome / Q000000981:diagnostic imaging / Q000503:physiopathology; D055119:Elastic Modulus; D004867:Equipment Design; D006801:Humans; D008475:Median Nerve / Q000000981:diagnostic imaging* / Q000502:physiology; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D014159:Transducers; D014463:Ultrasonography; D014732:Vibration
keywords: Deformation; Elastography; Median nerve; Strain; Ultrasound