Systematic Review of Shoulder Imaging Abnormalities in Asymptomatic Adult Shoulders (SCRUTINY): Abnormalities of the glenohumeral joint.

Objective: The primary objective was to determine the population prevalence of glenohumeral joint imaging abnormalities in asymptomatic adults.

Method: We systematically reviewed studies reporting the prevalence of X-ray, ultrasound (US), computed tomography, and magnetic resonance imaging (MRI) abnormalities in adults without shoulder symptoms (PROSPERO registration number CRD42018090041). This report presents the glenohumeral joint imaging findings. We searched Ovid MEDLINE, Embase, CINAHL and Web of Science from inception to June 2023 and assessed risk of bias using a tool designed for prevalence studies. The primary analysis was planned for the general population. The certainty of evidence was assessed using a modified Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) for prognostic studies.

Results: Thirty-five studies (4 X-ray, 10 US, 20 MRI, 1 X-ray and MRI) reported useable prevalence data. Two studies were population-based (846 shoulders), 15 studies included miscellaneous study populations (1715 shoulders) and 18 included athletes (727 shoulders). All were judged to be at high risk of bias. Clinical diversity precluded pooling. Population prevalence of glenohumeral osteoarthritis ranged from 15% to 75% (2 studies, 846 shoulders, 1 X-ray, 1 X-ray and MRI; low certainty evidence). Prevalence of labral abnormalities, humeral head cysts and long head of biceps tendon abnormalities were 20%, 5%, 30% respectively (1 study, 20 shoulders, X-ray and MRI; very low certainty evidence).

Conclusion: The population-based prevalence of glenohumeral joint imaging abnormalities in asymptomatic individuals remains uncertain, but may range between 30% and 75%. Better estimates are needed to inform best evidence-based management of people with shoulder pain.