Ultrasound-guided versus blind subacromial corticosteroid and local anesthetic injection in the treatment of subacromial impingement syndrome: A randomized study of efficacy

Abstract

Objectives: This study aims to compare the effects of ultrasound (US)-guided and blind subacromial corticosteroid and local anesthetic (LA) injection in the treatment of subacromial impingement syndrome (SIS) on shoulder pain, range of motion (ROM), and functionality.

Patients and methods: The prospective study was conducted between 01 February 2017 and 31 May 2017. A total of 29 patients with clinical findings and magnetic resonance imaging (MRI) consistent with SIS were randomized into two groups: 14 patients received US-guided subacromial corticosteroid and LA injection and 15 patients received a blind subacromial corticosteroid and LA injection. Patients were evaluated before and one month after treatment. One patient was lost to follow up. The primary outcome measure was a visual analog scale (VAS) for shoulder pain. Secondary outcomes were active shoulder ROM in flexion and abduction, the Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire and the modified Constant-Murley Score (CMS).

Results: Twenty eight patients (11 males, 17 females; mean age 39.5 in the US guided group and 42.5 in the blind group: range 20 to 64 years in both groups) completed the study. There was a significant improvement in VAS for shoulder pain, active ROM, DASH questionnaire score and modified CMS in both groups four weeks after treatment (p<0.05). There was no between-group difference in VAS, ROM or DASH questionnaire scores. Following treatment, the modified CMS in the US-guided injection group was higher than in the blind injection group (p=0.02). However, when the mean change in modified CMS in the US-guided injection group was compared to that of the blind injection group, the difference was insignificant (p=0.23).

Conclusion: Both US-guided and blind subacromial steroid injection improve shoulder pain, ROM, and functionality in SIS; one treatment option was not found to be superior to the other. Therefore, blind injection can be performed in clinical settings where US is not available. Equally, blind injection can also be performed in patients who have a definite diagnosis of SIS based on clinical and MRI findings.