Efficacy of Lidocaine/Prilocaine Cream During Dry Needling of Upper Trapezius Myofascial Trigger Points: A Double-blinded Randomized Controlled Trial

OBJECTIVE This study aimed to evaluate the efficacy of a eutectic mixture of local anesthetics (EMLA) cream in reducing pain during dry needling (DN) of active myofascial trigger points (MTrP) in the upper trapezius muscle. METHODS This prospective, randomized, double-blind, placebo-controlled trial was conducted with participants aged 20 years and older who had active MTrP in the upper trapezius muscle. Recruitment occurred from 11 July 2023 to 4 March 2024. Participants were randomly assigned to receive either EMLA cream (n = 32) or a placebo cream (n = 32) which was applied over the active MTrP 60 minutes prior to the DN procedure. After the DN procedure, patients rated their pain using a 100-mm visual analog scale during DN (VASTrP) as the primary outcome and during the needle’s skin penetration (VASskin) as the secondary outcome. RESULTS Patients in the EMLA group reported significantly lower scores for VASTrP and VASskin than those in the placebo group (p < 0.05). Specifically, 53.1% of patients in the EMLA group reported ‘moderate to severe pain’ according to VASTrP, significantly lower than the 78.10% in the placebo group (p = 0.035). Moreover, 65.63% of patients in the EMLA group reported ‘no pain’ on the VASskin scale, compared to just 15.63% in the placebo group (p < 0.001). Importantly, no significant adverse events associated with EMLA were observed. CONCLUSION EMLA cream is effective in providing analgesia during DN of an active MTrP in the upper trapezius muscle.