Associations Between Gluteus Medius Trigger Points With Hip Passive Range of Movement and Muscle Strength in Adults With Chronic Nonspecific Low Back Pain: A Cross-Sectional Study

Abstract

Objective: The purpose of this study was to investigate whether there is a relationship between gluteus medius trigger points with hip passive range of motion and hip muscle strength in people with chronic nonspecific low back pain (LBP). Methods: This was a cross-sectional, blinded study that took place in 2 rural communities in New Zealand. Assessments were carried out in physiotherapy clinics in these towns. A total of 42 participants over 18 years old experiencing chronic nonspecific LBP were recruited. After meeting inclusion criteria, participants completed the following 3 questionnaires: Numerical Pain Rating Scale, Oswestry Disability Index, and Tampa Scale of Kinesiophobia. The primary researcher (a physiotherapist) assessed each participant's bilateral hip passive range of movement (using an inclinometer) and muscle strength (using a dynamometer). Following this, a blinded trigger point assessor examined the gluteus medius muscles for the presence of active and latent trigger points. Results: General linear modeling using univariate analysis revealed that there was a positive association between hip strength and trigger point status (P =.03 left internal rotation, P =.04 right internal rotation, and P =.02 right abduction). Participants with no trigger points showed higher strength values (eg, right internal rotation standard error: 0.64), and those with trigger points showed lower strength. Overall, muscles exhibiting latent trigger points were the weakest (eg, right internal rotation standard error: 0.67). Conclusion: The presence of active or latent gluteus medius trigger points was associated with hip weakness in adults with chronic nonspecific LBP. There was no association between gluteus medius trigger points and hip passive range of movement.