The abstract is read at the publisher; the summary is JClub's.
Posterior deltoid muscle volume exceeds middle deltoid volume by 55.36 ml (95% CI 54.14–56.58, p<0.0001) in 5,239 UK Biobank participants’ Dixon MRI scans.
- Why it matters: Injection site selection may depend on regional muscle size, but evidence comparing middle versus posterior deltoid volumes in vaccine-eligible groups is limited.
- What they did: Deltoid muscles in 43 UK Biobank Dixon MRI scans were manually segmented into anterior, middle, and posterior regions, then a MONAI deep learning model (Dice score=0.78) produced regional volumes for 5,239 participants by UK flu vaccination eligibility (A n=1,760; B n=1,744; C n=1,735), sex, and side.
- The result: Posterior–middle differences were largest in Group A, then B, then C, were greater in men, and greater on the right side (all p<0.0001), supporting further assessment of the posterior deltoid as a potentially safer injection target.
The findingWhy it mattersWhat they didThe result
AI summary of the abstract · may contain errors · not medical advice · read the paper.