Intracarpal midazolam: does it offer better pain relief than dexamethasone in carpal tunnel syndrome patients? A randomized double-blind clinical trial

Abstract

Background: Intracarpal injection of steroids has produced favorable effects in patients with carpal tunnel syndrome (CTS); however, it still carries some drawbacks. Perineural midazolam injection has some promising effects in chronic neuralgia. This study focused upon pain visual analog scale (VAS) improvement, and Boston Carpal Tunnel Syndrome Questionnaire (BCTQ) improvements when comparing intracarpal injection of midazolam versus dexamethasone. Methods: One hundred and thirty-four patients with mild to moderate CTS were randomized (1:1 ratio) to receive intracarpal 3 ml bupivacaine 0.5% with either 8 mg dexamethasone in 2 ml saline (group DX) or 2 mg midazolam in 2 ml saline (group MZ). VAS and BCTQ were assessed preintervention and postintervention (1st week, 1st, 3rd, and 6th months) Results: The VAS showed a significantly lower value in MZ than the DX group with median value of 2 (maximum-minimum = 1–3) in MZ and 4 (2–5) in DX by the 6th month p = 0.049. Intragroup comparison of follow-up VAS to the baseline value showed significant decreases in the MZ group during the whole study period, whereas in DX the decrease was noticed by the 1st week and 1st month only. In postinterventional BCTQ, both symptom severity (SSS) and functional severity (FSS) scores were significantly lower in MZ rather than DX group after the 1st, 3rd, and 6thmonths where SSS (p = 0.029, 0.048, 0.04) and FSS (p = 0.04, 0.019, 0.003) in consequence. Conclusions: Intracarpal injection of midazolam offers a longer duration of pain relief and higher hand functional improvement scores in comparison to dexamethasone.