Local corticosteroid injection versus physical therapy for the treatment of carpal tunnel syndrome: A systematic review and meta-analysis of randomized controlled trials

The comparative effect of commonly used conservative treatments for carpal tunnel syndrome remained controversial. The purpose of this study was to compare the clinical effect of local corticosteroid injection and physical therapy for the treatment of carpal tunnel syndrome. A systematic literature search of PubMed, EMBASE, and Cochrane library was conducted to identify relevant randomized clinical trials published before 21st Mar 2023. Two independent reviewers assayed quality of included studies using the Cochrane collaboration risk of bias tool. Relevant data were extracted and pooled analyses were conducted. Outcome measurements included Boston Carpal Tunnel Syndrome Questionnaire, visual analogue scale and some electrophysiology tests, while the former two were set as the primary outcomes. Subgroup analysis and sensitive analysis were performed and publication bias was evaluated. Heterogeneity among the included studies was examined using the I2 statistic. After selection, 12 studies were identified eligibility for inclusion. Only one study was found to have a high risk of bias. Pooled data of primary outcomes did not show any differences between treatments, and subgroup analysis supported the results. However, patients treated with local corticosteroid injection showed better improvement in distal motor latency (p = 0.002) and compound muscle action potential (p = 0.04). Some studies failed to pass the sensitive analysis, indicating the related analysis might be not so stable. A slight publication bias was observed in subgroup analysis of function scales, among three publication bias test. In conclusion, compared to physical therapy, local corticosteroid injection might have better treatment effects on carpal tunnel syndrome.