OBJECTIVE: To determine the reliability of quantitative measures of the long head of the biceps tendon using an ultrasound-imaging system. DESIGN: Intra- and inter-rater reliability study. SUBJECTS/PATIENTS: Thirty-one participants without shoulder pain. METHODS: All participants took part in 3 ultrasound imaging sessions; they were assessed by 2 evaluators (inter-rater reliability), one of whom assessed them twice (intra-rater reliability). All measurements were taken at the widest identified part of the tendon using longitudinal and transverse views. Measurements of the long head of the biceps tendon included width, thickness and cross-sectional area. Intraclass correlation coefficients and minimal detectable change were used to characterize reliability. RESULTS: Intra- and inter-rater reliabilities were excellent for all measures when the mean of 2 measures were considered, except for inter-rater reliability of the width, for which it ranged from 0.76 to 0.86. Minimal detectable change ranged from 0.3 to 1.6 mm for width and thickness, and from 2.8 to 4.9 mm2 for cross-sectional area. CONCLUSION: Ultrasound measurement of the long head of the biceps tendon is a highly reliable method, except for the width. When measuring the long head of the biceps tendon, a mean of 2 measurements is recommended. Now that reliability has been shown in healthy individuals, the next step will be to determine the validity/reliability of these quantitative measures in symptomatic shoulders.
OBJECTIVE: To determine the reliability of quantitative measures of the long head of the biceps tendon using an ultrasound-imaging system. DESIGN: Intra- and inter-rater reliability study. SUBJECTS/PATIENTS: Thirty-one participants without shoulder pain. METHODS: All participants took part in 3 ultrasound imaging sessions; they were assessed by 2 evaluators (inter-rater reliability), one of whom assessed them twice (intra-rater reliability). All measurements were taken at the widest identified part of the tendon using longitudinal and transverse views. Measurements of the long head of the biceps tendon included width, thickness and cross-sectional area. Intraclass correlation coefficients and minimal detectable change were used to characterize reliability. RESULTS: Intra- and inter-rater reliabilities were excellent for all measures when the mean of 2 measures were considered, except for inter-rater reliability of the width, for which it ranged from 0.76 to 0.86. Minimal detectable change ranged from 0.3 to 1.6 mm for width and thickness, and from 2.8 to 4.9 mm2 for cross-sectional area. CONCLUSION: Ultrasound measurement of the long head of the biceps tendon is a highly reliable method, except for the width. When measuring the long head of the biceps tendon, a mean of 2 measurements is recommended. Now that reliability has been shown in healthy individuals, the next step will be to determine the validity/reliability of these quantitative measures in symptomatic shoulders.