Quantitative MSK ultrasound of long head of biceps brachii

Rotator cuff deficiency increases superior translation of the humeral head in relation to the glenoid fossa, causing the the long head of the biceps brachii tendon (LHBT), a humeral head depressor, to be subject to overuse injury. Next to this, the LHBT passes through the anterior-superior portion of the rotator cuff tendons, the most prevalent site for tears. Among all the biceps pathology concomitant with torn rotator cuffs, tendinopathy is the most common. Clinical symptoms and physical examinations have shown poor sensitivity for detecting biceps tendinopathy and MSK ultrasound hasbeen recommended as the first-line diagnostic image modality.

The present study aimed to explore the morphological differences of the LHBT in shoulders with and without deficient rotator cuffs by using quantitative ultrasound and to investigate the utility of the LHBT morphology in discriminating supraspinatus full thickness tears (SSFT).

SSFT was associated with the morphology changes of the extraarticular LHBT examined using ultrasound, comprising an increase in the thickness and cross-sectional area and a reduction in the flattening ratio. Age, gender, biceps peritendinous effusion, and medial subluxation were shown to modify the LHBT appearance, but the difference between shoulders with small-tomedium and large-sized tears were not significant. Among the morphological parameters of the LHBT, the flattening ratio was the best discriminator of SSFT and may be utilized in future largescale studies for detection of supraspinatus tendon deficiency of different grades.

> From: Chang et al., PLoS ONE 9 (2014) e113803(Epub ahead of print). All rights reserved to The Author(s). Click here for the Pubmed summary.