RESUMEN
INTRODUCTION: MPS is a chronic disorder caused by myofascial trigger points, leading to pain and limited neck movements due to impacted fascia. Studies have reported reduced fascia slides in chronic low back pain, but limited fascia slides in MPS patients are still unreported. AIM: We determined differences in upper trapezius' deep fascia slides between MPS and non-MPS participants. METHODS: Between January-August 2019, participants from diverse work sectors were recruited in Manila. An expert physiotherapist diagnosed MPS, while non-MPS participants performed full painless cervical movements. Participants underwent upper trapezius deep fascia scans on both shoulders while performing six cervical movements. An HS1 Konica Minolta ultrasound recorded the data. Two blinded physiotherapists used Tracker 5.0 © 2018 to analyze videos and quantify deep fascia slides by measuring the distance between two x-axis points. The Multivariate analysis of variance (MANOVA) assessed deep fascia slide differences in six active cervical movements. Pillai's Trace, with a range of 0-1 and a p-value of <0.05, was set. Effect sizes in individuals with and without MPS were calculated using Hedges' g and Cohen's d. RESULTS: Of the 327 participants (136 non-MPS, 191 MPS), 101 MPS participants had shoulder pain for <1 year and 103 experienced unilateral pain. The study examined 3800 ultrasound videos but found no significant difference in deep fascia slides across cervical movements between MPS and non-MPS groups (Pillai's Trace = 0.004, p = 0.94). Minor differences in deep fascia displacement were observed, with small effect sizes (g = 0.02-0.08). CONCLUSION: A limited deep fascia slide does not characterize MPS participants from non-MPS participants.