Corticosteroid injection for carpal tunnel syndrome: A meta-analysis comparing ultrasound guided approach with landmark approach

Objective: To assess and compare the clinical and functional outcomes of corticosteroid injections in patients with carpal tunnel syndrome, focusing on two different approaches: ultrasound -guided and landmark -guided. Methods: A systematic search was conducted in PubMed, Scopus and Embase databases for relevant studies published prior to 30th April 2023. Studies that were either randomized controlled trials or had a cohort design were included. The review assessed symptom severity, functional status, electrodiagnostic parameters, complications, need for surgical intervention, visual analogue score, and grip strength. Pooled effect sizes were reported as relative risk (RR) or weighted mean difference (WMD). Results: A total of 8 articles were included. Compared to those that received steroid injection using landmark approach, those with ultrasound guided approach had lower symptom severity scale (SSS) score on Boston Carpal Tunnel Questionnaire (BCTQ) [WMD -0.50, 95% CI: -0.94, -0.07; I2=78.0%, N=7], lower risk of "any complications" [RR 0.58, 95% CI: 0.36, 0.93; I2= 22.9%, N=3] and lower risk of need for surgical intervention [RR 0.55, 95% CI: 0.34, 0.89; I2= 3.0%, N=2]. All other parameters were similar in the two groups i.e., functional status scale (FSS) score, visual analogue score (VAS) and grip strength. The electrophysiological findings were similar in the two groups. Conclusion: Findings suggest that ultrasound guided approach may be better than landmark guided approach especially in terms of alleviation of symptoms, reducing the risk of complications and need for surgical intervention. However, larger trials with long term follow up may provide conclusive evidence.