Inter- and intra-observer reproducibility of ultrasound analysis of the long head of the biceps

Abstract

IntroductionUltrasound assessment of the long head of the biceps (LHB) is difficult. The aim of the present study was to analyze the inter- and intra-observer reproducibility of 2 ultrasound cross-sections not previously assessed: humeral head apex (image 1) and bicipital groove entrance (image 2). HypothesisThese ultrasound cross-sectional images allow reliable and reproducible analysis of the intra-articular LHB. Material and methodsA single-center prospective study was conducted. Inter-observer reproducibility was assessed between 2 radiologists in 20 healthy shoulders (asymptomatic group) and 35 painful shoulders (symptomatic group); intra-observer reproducibility was assessed for 1 observer in 10 healthy shoulders. Quantitative parameters comprised short and long axes and transverse area, and qualitative parameters comprise echogenicity and LHB position. ResultsOn images 1 and 2, inter-observer agreement on the 3 quantitative parameters was good to excellent in both subject groups (p<0.05), and more precise and highly reproducible for image 1. Agreement on the 2 qualitative parameters was excellent (p<0.001). Intra-observer reproducibility results were non-significant on all parameters. DiscussionThe 2 intra-articular LHB cross-sections proved reliable and reproducible in painful and in healthy shoulders. A standardized ultrasound protocol could thus enhance the precision of LHB assessment and treatment. The difficulties of LHB measurement, often related to shoulder pathology, may, however, hinder interpretation. Level of evidenceIII, prospective intra- and inter-observer study.