Ultrasound Guidance Is Not Superior in Subacromial Bursa and Intraarticular Injections but Superior in Bicipital Groove: A Meta-analysis of Randomized Controlled Trials

Purpose: To perform a meta-analysis comparing the clinical and functional outcomes of ultrasound-guided (USG) and blind injections for shoulder pain. Method: The Embase, Cochrane Library, and PubMed databases were searched from database inception to April 7, 2021. Clinical and functional outcomes included the visual analog scale (VAS) pain score, abduction, flexion, American Shoulder and Elbow Surgeons Assessment Form (ASES) score, Constant-Murley Shoulder (CMS) score, Shoulder Pain and Disability Index (SPADI), Shoulder Disability Questionnaire (SDQ) score, and Shorted Disabilities of the Arm, Shoulder and Hand (Quick DASH) score. Dichotomous outcomes were assessed with mean differences (MDs) and 95% confidence intervals (95% CIs). Results: Fifteen studies that compared USG and blind injections were included. No significant difference was found in the VAS score between the blind group and USG group (MD 0.41 [-0.02, 0.84]; I-2 = 79%; P = .06). Subgroup analysis of the brachial bicipital groove indicated that the USG group had less pain than the blind group (MD 1.50 [0.54, 2.46]; I-2 = 64; P = .002). The USG injection patients had better postoperative abduction (MD -3.08 [-5.19, -0.98], I-2 = 0, P = .004) and flexion (MD -3.36 [-5.56, -1.16]; I-2 = 0; P= .003) than the blind group. Additionally, the USG injection patients had better CMS scores than the blind injection patients (MD -12.95 [-25.60, -0.29]; I-2 = 96; P = .04). However, subgroup analysis showed no significant difference in the subacromial bursas and glenohumeral joints of CMS score (MD -13.22 [-29.93, 3.94]; I-2 = 97; P < .0001). No significant difference was found in the SPADI, ASES score, or SDQ score between the groups. Conclusions: Ultrasound guidance is not superior in the subacromial bursa and glenohumeral joint injections in pain or function. However, injection in the brachial bicipital groove, is still superior to blind injection of pain relief.