Sumanont S, et al. - Corticosteroid injection (CI) into the subacromial space is a palliative treatment option for subacromial impingement syndrome (SIS). This study investigated if high volume (< 5 ml) better than low volume (≥ 5 ml) of CI injection with respect to pain reduction. It was evident that corticosteroid injection had acceptable pain and functional outcomes and, higher volume vs. lower volume had a lower American shoulder and elbow surgeons (ASES), visual analog score (VAS), and risk of complication. However, no statistically significant differences were observed between groups.