The Effect of Quadratus Lumborum Muscle Energy Technique on Low Back Pain and Diaphragmatic Electrophysiological Outcomes

Objectives: Quadratus lumborum (QL) is included in the list of accessory muscles of expiration. This muscle contracts to depress the ribs. It stabilizes the diaphragm for respiration. A tight/stiff QL prevents the rib cage from fully expanding to take a deep breath and pulls over the diaphragm and surrounding tissues. This affects chest expansion and breathing patterns. This leads to faulty posture adaptation and disruption in breathing patterns. This study aims to assess the effect of muscle energy technique (MET) of QL on pain, and diaphragm activity in individuals with nonspecific low back pain. Methods: This study was conducted using a quasi-experimental study and the research population included 65 individuals with non-specific low back pain. Two groups were formed based on the score of self-evaluation of the breathing questionnaire, SEBQ 11, and SEBQ 11 and pre-intervention assessment of numeric pain rating scale (NPRS), surface electromyography (EMG) of the diaphragm, maximum inspiratory pressure (Pimax) and chest expansion was assessed. MET to QL was given and immediate post-measurements of the same were assessed. Considering the normality, data were analyzed using paired t-test and Wilcoxon’s rank sum test using Medcalc software, version 22.017.  Results: Numeric pain rating scale (NPRS) of both groups was statistically significant (P 0.0001), amplitude in SEBQ 11 was significant (P 0.0166), and Pimax was highly significant in both groups (P=0.0001). Discussion: MET of QL affects pain and lung function in patients with nonspecific low back pain.