Effects of Spinal Manipulation on Peak Loading and Trunk Displacement During Unanticipated Trunk Perturbations of Participants with and without Chronic Low Back Pain
Effects of Spinal Manipulation on Peak Loading and Trunk Displacement During Unanticipated Trunk
Perturbations of Participants with and without Chronic Low Back Pain
Matt Linsenmayer1,Andrew J. Ross1, Malissa Corbett1, Terrence Schwing1, Stevan Walkowski2, Brian C. Clark2,3, David A. Goss Jr.3, James S. Thomas1,2,3
1School of Rehabilitation and Communication Sciences, Division of Physical Therapy, Ohio University, 2 Ohio Musculoskeletal & Neurological Institute,
3Department of Biomedical Sciences College of Osteopathic Medicine, Ohio University, Athens, OH
Figure 3: A participant is depicted prior to a single HVLA thrust manipulation to a selected segment of the lumbar spine.
Figure 2: A skeletal reconstruction of the participant using Motion Monitor software (version 7.78, Chicago, IL).
Figure 1: A participant is depicted secured in the reference frame prior to a perturbation.
▪ A total of eighteen adults (9 male, 9 female) participated in the study. Participants were recruited by flyers posted in the local university community.
▪ Eight adult participants (3 male, 5 female)
▪ Mean age of 28.5 ±1.25 years
▪ Mean height of 166.7 ±.92 cm
▪ Mean mass of 67.1 ±1.36 kg
▪ McGill Pain Questionnaire-
Present Pain Intensity
▪ Mild = 4 participants
▪ Discomforting = 4 participants
▪ Tampa Scale for Kinesiophobia
▪ Mean score = 33.5
▪ Ten adult participants (6 male, 4 female)
▪ Mean age of 22.9 ±1.61 years
▪ Mean height of 174.6 ±.73 cm
▪ Mean mass of 69.9 ±1.01 kg
▪ No history of LBP
Figure 4: The difference in group hip flexion displacement is shown.* indicates a significant difference between groups. Error bars represent the standard error of the mean.
Figure 6: Depicted are the mean peak impulses by group and by time (i.e., pre-HVLA manipulation and post-HVLA manipulation) during perturbations. Error bars represent the standard error of the mean.
Figure 5: Depicted is the mean peak load during perturbations in each group.* indicates a significant difference between groups. Error bars represent the standard error of the mean.
▪ Our results indicate that a single HVLA thrust manipulation to a segment of the lumbar spine had no effect on 1) lumbar or hip flexion displacement, 2) peak load, 3) impulse, or 4) onset latency of the erector spinae during trunk flexion perturbations. It is unknown if increased dosage of manual or manipulative therapy would have led to significant changes post-HVLA manipulation due to mechanical and/or neurophysiological effects.
▪ Participants with chronic LBP were found to have a significantly greater hip flexion displacement during trunk flexion perturbations.
▪ However, there was no difference between groups in onset latency of the erector spinae during trunk flexion perturbations. This finding, along with findings that the presence of chronic LBP does not systematically alter cortical excitability impacting the motor evoked potential of the erector spinae (Figure 8) (Clark et al., 2011), show that initially there may be no difference in activation of the erector spinae musculature between groups. However, further work is required to determine if there is a difference in motor control or quality of muscle activity (specifically of the hip extensors) after initial activation.
▪ Additionally, the peak load in participants with chronic LBP was significantly less than the peak load in healthy controls.
▪ This difference cannot be explained by a difference in impulse between groups as there was no significant difference found. Since participants with chronic LBP had greater hip excursion during flexion perturbations, it seems likely that these individuals experienced the load over a longer duration leading to a lower peak load.
▪ Quantitative data to confirm explanations for our results requires further study. Specifically, EMG data will be further explored including the duration and amplitude of muscle activation. The activity of the gluteus maximi and hamstring musculature must be assessed to analyze motor control of the hip. In addition, the dosage of manual or manipulative therapy must be increased in order to determine if main effects of time were limited solely due to lack of an adequate intervention.
Figure 8: Depicted are motor-evoked potentials in the erector spinae during single-pulse transcranial magnetic stimulation to cortical areas representing the paraspinal musculature. Error bars represent the standard error of the mean.
Figure 7:Depicted are mean onset latencies in the erector spinae during trunk flexion perturbation trials. Error bars represent the standard error of the mean.