Spinal Manipulation and Spinal Mobilization Effects in Participants With and Without Back Pain

Canadian Institutes of Health Research (CIHR), Fonds de la Recherche en Santé du Québec, Unité de recherche en santé musculosqulettique

The objective of the present study is to compare the neuromechanical responses to spinal manipulation and spinal mobilization in participants with chronic nonspecific middle back pain.

Although evidences suggest a similar effectiveness of spinal manipulation and spinal mobilization, there is no study that compares the neuromechanical effects of these manual therapies in a experimental context and with the standardization of both interventions. Therefore, the objective of the present study is to compare the neuromechanical responses to spinal manipulation (low-amplitude and high-velocity dynamic thrust) and spinal mobilization (repetitions of a low-amplitude and low-velocity nonthrust movement) in participants with and without chronic nonspecific back pain.

Twenty-six participants with chronic nonspecific back pain will participate in two experimental sessions. During the first session, each participant will received either a spinal manipulation of a spinal mobilization of their thoracic spine preceded and followed by the assessment of their thoracic spine stiffness. The second session (24 to 48h after) will be identical but with the other experimental condition (spinal manipulation or spinal mobilization).

Twenty-six participants with chronic nonspecific back pain will participate in two experimental sessions. During the first session, each participant will received either a spinal manipulation of a spinal mobilization of their thoracic spine preceded and followed by the assessment of their thoracic spine stiffness. The second session (24 to 48h after) will be identical but with the other experimental condition (spinal manipulation or spinal mobilization).

Three repetitions of a low-velocity and low-amplitude nonthrust movement delivered posteroanteriorly to a thoracic vertebra

Global stiffness was defined as the slope of the straight-line best fitting the force-displacement data between 10 and 45 N

Terminal stiffness was defined as the ratio of the variation of force and displacement between 10 and 45 N

Pressure provoked pain intensity was assessed immediately after each spinal stiffness assessment using a 0 to 100 visual analog pain scale minimum value=0, maximum value=100. 0 is no pain while 100 is the worse outcome

To assess the muscular response during therapeutic modalities, the resulting bipolar sEMG signals were first digitally band-pass filtered using a frequency bandwidth of 20-450 Hz (2nd order Butterworth filter). For SMa, the peak root mean square (RMS) value was computed for each electrode using a 250 ms window (125 ms before and 125 ms after the peak force). The RMS values obtained for each electrode were then normalized (nRMS) to the respective RMS value calculated during the sEMG normalization trial.

To assess the muscular response during therapeutic modalities, the resulting bipolar sEMG signals were first digitally band-pass filtered using a frequency bandwidth of 20-450 Hz (2nd order Butterworth filter). For SMa, the peak root mean square (RMS) value was computed for each electrode using a 250 ms window (125 ms before and 125 ms after the peak force). The RMS values obtained for each electrode were then normalized (nRMS) to the respective RMS value calculated during the sEMG normalization trial.

Inclusion Criteria: presenting or not a history of chronic nonspecific back pain Exclusion Criteria: History of back trauma or surgery Severe osteoarthritis Inflammatory arthritis Vascular conditions Contraindication to the use of spinal manipulation or spinal mobilization Pregnancy Scoliosis