Reliability of sonographic muscle thickness measurements of the thenar and hypothenar muscles.

Introduction This study was undertaken to assess the intra- and interrater reliability of sonographic thickness measurements of the thenar and hypothenar muscles.

METHODS: The thickness of the thenar and hypothenar muscles of both hands of 15 volunteers (7 male, 8 female) were evaluated with a 4-13-MHz linear probe by 2 examiners who were blinded to each other's measurements. Interrater reliability was then evaluated. To assess intrarater reliability, the first examiner also performed a second measurement after an interval of at least 1 day.

RESULTS: Mean age of the subjects was 31.1 ± 9.0 years. Test-retest reliability showed excellent intrarater reliability (intraclass correlation coefficient range: 0.889-0.963) and substantial to excellent results for interrater reliability (intraclass correlation coefficient range: 0.692-0.937).

DISCUSSION: We found that ultrasound is a reliable method for thickness measurements of the thenar and hypothenar muscles. Muscle Nerve 57: E14-E17, 2018.