Correlation Between Posterior Oblique Sling Activation and Contralateral Glenohumeral Stability in Low Back Pain

Objective: This study will be conducted to investigate the relationship between the amplitude of posterior oblique sling muscles; ipsilateral gluteus maximus (GM) and contralateral latissmus Dorsi (LD), and the amount of anterior translation of humeral head (ATHH) of the contralateral glenohumeral joint (GHJ) in subjects with unilateral chronic low back pain (CLBP) during ipsilateral prone knee extension (PHE) test. Methods: The study will be conducted on thirty subjects (15 patients with CLBP and 15 healthy subjects). Ipsilateral GM and contralateral LD amplitude will be recorded by surface EMG during PHE of the limb at the painful side and correlated to ATHH of contralateral GHJ as measured by ultrasonography. Hypothesis: There won't be a significant relationship between the amplitude of posterior oblique sling muscles (GM and contralateral LD) during PHE for the ipsilateral leg and the amount of ATHH of the contralateral GHJ in patients with unilateral CLBP.