Ultrasound Assessment of the Coracohumeral Ligament and Rotator Interval and Its Association With Physical Function in Patients With Adhesive Capsulitis of the Shoulder: A Scoping Review

In adhesive capsulitis (AC), ultrasound (US) assessment of the coracohumeral ligament (CHL) and rotator interval (RI) is widely performed, but the relationship between these imaging findings and clinical symptoms has not been adequately synthesized.This scoping review aimed to map the evidence on associations between US findings of the CHL and RI and clinical assessments (range of motion (ROM), pain, and patient-reported outcomes) in AC, and to identify implications for clinical practice and future research.Following the Joanna Briggs Institute (JBI) methodology and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) (protocol registered on the Open Science Framework), four bibliographic databases (PubMed, Scopus, Ichushi-Web, and PEDro) and two trial registries (International Clinical Trials Registry Platform (ICTRP) and ClinicalTrials.gov)were searched through January 2026 for English-or Japanese-language records.Studies were eligible if they investigated patients with AC and examined associations between US findings of the CHL or RI and physical function.Two reviewers independently screened studies and charted data on study characteristics, US assessments, physical function, and key findings, with disagreements resolved by consensus, and data were synthesized descriptively.Of 2,488 records identified, 17 met the eligibility criteria (16 studies and one trial registration).CHL thickness, the most frequently assessed parameter, was associated with limited external rotation ROM in most studies, whereas the association between RI vascularity and pain was inconsistent; substantial heterogeneity was observed in staging, US measurement, and outcome assessment methods, and an author-developed, hypothesis-generating clinical reasoning matrix was proposed.CHL thickness appears to be a promising US indicator of external rotation limitation in AC, whereas evidence for the clinical significance of RI vascularity remains insufficient, and standardized staging and US protocols are needed to clarify the utility of US-based assessment for treatment decision-making.