Bridge Maneuvers in Low Back Pain: Assessment of Internal and External Responsiveness

Objective: This study aimed to examine the responsiveness of bridge maneuvers in subjects with low back pain (LBP) with respect to these outcomes. Methods: One hundred and thirty-nine patients with subacute and chronic LBP participated in a physical therapy program averaging 7.46 sessions of supervised exercises and home exercises to improve lumbar stability. At the beginning of the program and after the last session, participants completed the Oswestry Disability Index (ODI-I) and the Pain Numerical Rating Scale (NRS), and performed Supine Bridge test (SBT), Right Side Bridge Test (RBT), Left Side Bridge Test (LBT), and Prone Bridge Test (PBT). Global perception of effectiveness was measured with a 7-point Global Perceived Effect Questionnaire. Results: The optimal cutoff points were approximately 38.5 seconds for the Prone Bridge Test (PBT), (44% sensitivity; 78% specificity), 29.5 seconds for the RBT (55% sensitivity; 67% specificity), and 142 seconds for the SBT (45% sensitivity; 67% specificity). The areas under curves ranged from 0.56 (SBT) to 0.61 (PBT and RBT). Low to moderate significant relationships (p < .01) among bridge maneuvers, pain and disability (-0.23 to -0.39) and high correlations among each bridge maneuver and each other (0.69-0.81) emerged. Conclusion: Although bridge maneuvers were responsive to changes in lumbar stability and correlated significantly with pain and disability, these measures were not sufficiently sensitive or specific at baseline to predict these outcomes.