Static and Dynamic Shoulder Imaging to Predict Initial Effectiveness and Recurrence After Ultrasound-Guided Subacromial Corticosteroid Injections.

OBJECTIVE: To explore factors contributing to initial effectiveness and recurrence after ultrasound (US)-guided subacromial corticosteroid injections by assessing clinical measurements and static and dynamic shoulder US images.

DESIGN: Retrospective cohort study.

SETTING: Rehabilitation outpatient clinic.

PARTICIPANTS: Adults with shoulder pain referred for injection therapy (N=164).

INTERVENTION: US-guided subacromial corticosteroid injection.

MAIN OUTCOME MEASURES: The association of initial effectiveness (defined as >50% decrease in any of the 3 pain subdomains after the first injection) and recurrent shoulder pain that required repeated intervention with record-based clinical measurements and static/dynamic shoulder US.

RESULTS: This study included 164 patients, 106 of whom were responsive to a first injection. Among the 106 participants, 42 received a second injection because of recurrent shoulder pain. By using the multivariate logistic regression analysis, initial effectiveness was positively associated with right handedness, grade 2 subacromial impingement during the dynamic US examination, and bicipital groove tenderness. However, these patients had a negative association with subdeltoid bursitis, grade 3 subacromial impingement, and shoulder stiffness. Subdeltoid bursitis and a positive painful arc test were predictors of recurrent shoulder pain that necessitated a repeated injection in the Cox proportional hazards model.

CONCLUSIONS: The initial effectiveness and recurrence after US-guided subacromial corticosteroid injection were associated with certain clinical measurements and static and dynamic shoulder US, which should be carefully evaluated (and can be used) to guide the best treatment outcomes.