Ultrasound-Guided Percutaneous Electrical Nerve Stimulation versus Surgery for Women with Unilateral Carpal Tunnel Syndrome: A Randomized Parallel-group Trial.

The aim of this clinical trial was to compare the outcomes of the application of ultrasound-guided percutaneous nerve stimulation (PENS) targeting the median nerve vs. surgery for improving pain and function in women with CTS. In this randomized parallel-group trial (ClinicalTrials.gov, NCT04246216), 70 women with CTS were randomly allocated to either PENS (n=35) or surgery (n=35) group. Hand pain intensity (mean pain and the worst pain experienced) was the primary outcome. Functional status and symptoms severity (Boston Carpal Tunnel Questionnaire, BCTQ) and self-perceived improvement (Global Rating of Change, GROC) were the secondary outcomes. Outcomes were assessed at baseline, and one, three, six, and twelve months after each intervention. Analysis was performed by intention to treat with mixed ANCOVAs adjusted for baseline outcomes. Analyses showed an adjusted advantage for PENS at one (Δ -2.0, 95%CI -2.9 to -1.1) and three (Δ -1.4, 95%CI -2.3 to -0.5) months for mean pain, at one (Δ -2.2, 95%CI -3.3 to -1.1), three (Δ -1.75, 95%CI -2.9 to -0.6) and six (Δ -1.7, 95%CI -2.8 to -0.6) months in the worst pain intensity, and at one (Δ -0.95, 95%CI -1.1 to -0.8), three (Δ -0.55, 95%CI -0.8 to -0.3) and six (Δ -0.4, 95%CI -0.6 to -0.8) months in function. Both groups exhibited similar changes in symptoms severity. Both groups reported similar improvement at twelve months in all outcomes. Symptoms and function improved in both groups, with PENS leading to better short-term outcomes than surgery. This clinical trial confirms that PENS applied with current understanding of pain mechanisms in CTS is as useful as surgery in women with CTS without denervation. The potential placebo effect of both interventions should not be ignored.