Spinal Manipulation
Conditions
Keywords
electromyography, biomechanical phenomena, dose-response relationship, musculoskeletal manipulations, spinal manipulation
Brief summary
The objective of the present study is to determine if spinal manipulations with a constant rate of force application but with different peak force and time to peak force lead to similar responses in healthy adults.
Detailed description
Although there are indirect evidences that the rate of force application modulates neuromuscular responses to spinal manipulation therapy (SMT) through peak force or thrust duration modulations, such an assumption remains to be confirmed. Therefore, the objective of the present study was to determine if different SMT force-time profiles where a constant rate of force application would be maintained (through the modulation of the peak force and the time to peak force) lead to similar neuromechanical responses. Based on the available data relative to the effect of SMT biomechanical parameters modulation, it was hypothesized that neuromuscular responses would be similar across SMT force-time profiles, while vertebral displacements would increase as SMT peak force increases.
Interventions
PROCEDURESpinal manipulation
Participants will lie down during the 45-minute experimental session. Vertebral displacements (cm) and muscle response amplitude (RMS value) will be recorded through kinematic markers (on T6, T7 and T8 spinous processes) and surface electromyography electrodes (on the left and right erector spinae at T6 and T8 vertebra level). Each SMT (4 per participant) will be delivered at T7 transverse processes by an apparatus. Responses during the thrust phase (duration equal to twice the time to peak force) and after the thrust (1,5s duration) will be compared between SMTs.
DEVICEApparatus used to deliver spinal manipulations
An apparatus using a servo-controlled linear actuator motor (Linear Motor Series P01-48x360, LinMot Inc., Switzerland) will be used to deliver spinal manipulations.
Sponsors
Fondation Chiropratique du Québec
Université du Québec à Trois-Rivières
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 50 Years
Healthy volunteers
Yes
Inclusion criteria
* Healthy adult
Exclusion criteria
* Thoracic or lumbar pain * History of back trauma or surgery * Severe osteoarthritis * Inflammatory arthritis * Vascular conditions * Contraindication to the use of SMT
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Left T6 Normalized Root Mean Square (RMS) Value | During the 150N spinal manipulation procedure, assessed up to 2 seconds following thrust onset | Normalized amplitude (RMS) of surface electromyography response. The normalisation was achieved by dividing the obtained RMS by the RMS value before thrust application. |
| Left T8 Normalized Root Mean Square (RMS) Value | During the 150N spinal manipulation procedure, assessed up to 2 seconds following thrust onset | Normalized amplitude (RMS) of surface electromyography response. The normalisation was achieved by dividing the obtained RMS by the RMS value before thrust application. |
| Right T6 Normalized Root Mean Square (RMS) Value | During the 150N spinal manipulation procedure, assessed up to 2 seconds following thrust onset | Normalized amplitude (RMS) of surface electromyography response. The normalisation was achieved by dividing the obtained RMS by the RMS value before thrust application. |
| Right T8 Normalized Root Mean Square (RMS) Value | During the 150N spinal manipulation procedure, assessed up to 2 seconds following thrust onset | Normalized amplitude (RMS) of surface electromyography response. The normalisation was achieved by dividing the obtained RMS by the RMS value before thrust application. |
| Vertebral Displacement of the Sixth Thoracic Vertebra | During the 150N spinal manipulation procedure, assessed up to 2 seconds following thrust onset | Absolute posterior to anterior vertebral displacement during the spinal manipulation in centimeter |
| Vertebral Displacement of the Seventh Thoracic Vertebra | During the 150N spinal manipulation procedure, assessed up to 2 seconds following thrust onset | Absolute posterior to anterior vertebral displacement during the spinal manipulation in centimeter |
| Vertebral Displacement of the Eighth Thoracic Vertebra | During the 150N spinal manipulation procedure, assessed up to 2 seconds following thrust onset | Absolute posterior to anterior vertebral displacement during the spinal manipulation in centimeter |
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Participants All volunteers will participate in an experimental session. Participants will be delivered four different spinal manipulations (SMT) at T7 with a rate of force application of about 2200 Newtons/seconds and a preload force of 25 Newtons (N). SMTs will differed in their time to peak force (ms) and peak force (N), respectively fixed as follow for each applied SMT: (1)57 ms / 150 N, (2)80 ms / 200 N, (3)102 ms / 250 N and (4)125 ms / 300 N. | 25 |
| Total | 25 |
Baseline characteristics
| Characteristic | Participants |
|---|---|
| Age, Continuous | 24.76 years STANDARD_DEVIATION 3.8 |
| Region of Enrollment Canada | 25 participants |
| Sex: Female, Male Female | 10 Participants |
| Sex: Female, Male Male | 15 Participants |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | — / — |
| other Total, other adverse events | 0 / 25 |
| serious Total, serious adverse events | 0 / 25 |
Outcome results
Primary
Left T6 Normalized Root Mean Square (RMS) Value
Normalized amplitude (RMS) of surface electromyography response. The normalisation was achieved by dividing the obtained RMS by the RMS value before thrust application.
Time frame: During the 250N spinal manipulation procedure, assessed up to 2 seconds following thrust onset
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Participants | Left T6 Normalized Root Mean Square (RMS) Value | 4.92 ratio | Standard Error 0.91 |
Primary
Left T6 Normalized Root Mean Square (RMS) Value
Normalized amplitude (RMS) of surface electromyography response. The normalisation was achieved by dividing the obtained RMS by the RMS value before thrust application.
Time frame: During the 300N spinal manipulation procedure, assessed up to 2 seconds following thrust onset
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Participants | Left T6 Normalized Root Mean Square (RMS) Value | 4.17 ratio | Standard Error 0.53 |
Primary
Left T6 Normalized Root Mean Square (RMS) Value
Normalized amplitude (RMS) of surface electromyography response. The normalisation was achieved by dividing the obtained RMS by the RMS value before thrust application.
Time frame: During the 150N spinal manipulation procedure, assessed up to 2 seconds following thrust onset
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Participants | Left T6 Normalized Root Mean Square (RMS) Value | 3.72 ratio | Standard Error 0.68 |
Primary
Left T6 Normalized Root Mean Square (RMS) Value
Normalized amplitude (RMS) of surface electromyography response. The normalisation was achieved by dividing the obtained RMS by the RMS value before thrust application.
Time frame: During the 200N spinal manipulation procedure, assessed up to 2 seconds following thrust onset
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Participants | Left T6 Normalized Root Mean Square (RMS) Value | 4.75 ratio | Standard Error 0.76 |
Primary
Left T8 Normalized Root Mean Square (RMS) Value
Normalized amplitude (RMS) of surface electromyography response. The normalisation was achieved by dividing the obtained RMS by the RMS value before thrust application.
Time frame: During the 150N spinal manipulation procedure, assessed up to 2 seconds following thrust onset
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Participants | Left T8 Normalized Root Mean Square (RMS) Value | 2.83 ratio | Standard Error 0.3 |
Primary
Left T8 Normalized Root Mean Square (RMS) Value
Normalized amplitude (RMS) of surface electromyography response. The normalisation was achieved by dividing the obtained RMS by the RMS value before thrust application.
Time frame: During the 250N spinal manipulation procedure, assessed up to 2 seconds following thrust onset
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Participants | Left T8 Normalized Root Mean Square (RMS) Value | 4.03 ratio | Standard Error 0.52 |
Primary
Left T8 Normalized Root Mean Square (RMS) Value
Normalized amplitude (RMS) of surface electromyography response. The normalisation was achieved by dividing the obtained RMS by the RMS value before thrust application.
Time frame: During the 200N spinal manipulation procedure, assessed up to 2 seconds following thrust onset
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Participants | Left T8 Normalized Root Mean Square (RMS) Value | 4.12 ratio | Standard Error 0.5 |
Primary
Left T8 Normalized Root Mean Square (RMS) Value
Normalized amplitude (RMS) of surface electromyography response. The normalisation was achieved by dividing the obtained RMS by the RMS value before thrust application.
Time frame: During the 300N spinal manipulation procedure, assessed up to 2 seconds following thrust onset
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Participants | Left T8 Normalized Root Mean Square (RMS) Value | 4.80 ratio | Standard Error 0.88 |
Primary
Right T6 Normalized Root Mean Square (RMS) Value
Normalized amplitude (RMS) of surface electromyography response. The normalisation was achieved by dividing the obtained RMS by the RMS value before thrust application.
Time frame: During the 150N spinal manipulation procedure, assessed up to 2 seconds following thrust onset
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Participants | Right T6 Normalized Root Mean Square (RMS) Value | 3.03 ratio | Standard Error 0.35 |
Primary
Right T6 Normalized Root Mean Square (RMS) Value
Normalized amplitude (RMS) of surface electromyography response. The normalisation was achieved by dividing the obtained RMS by the RMS value before thrust application.
Time frame: During the 200N spinal manipulation procedure, assessed up to 2 seconds following thrust onset
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Participants | Right T6 Normalized Root Mean Square (RMS) Value | 3.13 ratio | Standard Error 0.33 |
Primary
Right T6 Normalized Root Mean Square (RMS) Value
Normalized amplitude (RMS) of surface electromyography response. The normalisation was achieved by dividing the obtained RMS by the RMS value before thrust application.
Time frame: During the 300N spinal manipulation procedure, assessed up to 2 seconds following thrust onset
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Participants | Right T6 Normalized Root Mean Square (RMS) Value | 3.87 ratio | Standard Error 0.64 |
Primary
Right T6 Normalized Root Mean Square (RMS) Value
Normalized amplitude (RMS) of surface electromyography response. The normalisation was achieved by dividing the obtained RMS by the RMS value before thrust application.
Time frame: During the 250N spinal manipulation procedure, assessed up to 2 seconds following thrust onset
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Participants | Right T6 Normalized Root Mean Square (RMS) Value | 3.40 ratio | Standard Error 0.4 |
Primary
Right T8 Normalized Root Mean Square (RMS) Value
Normalized amplitude (RMS) of surface electromyography response. The normalisation was achieved by dividing the obtained RMS by the RMS value before thrust application.
Time frame: During the 300N spinal manipulation procedure, assessed up to 2 seconds following thrust onset
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Participants | Right T8 Normalized Root Mean Square (RMS) Value | 3.79 ratio | Standard Error 0.49 |
Primary
Right T8 Normalized Root Mean Square (RMS) Value
Normalized amplitude (RMS) of surface electromyography response. The normalisation was achieved by dividing the obtained RMS by the RMS value before thrust application.
Time frame: During the 250N spinal manipulation procedure, assessed up to 2 seconds following thrust onset
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Participants | Right T8 Normalized Root Mean Square (RMS) Value | 3.57 ratio | Standard Error 0.55 |
Primary
Right T8 Normalized Root Mean Square (RMS) Value
Normalized amplitude (RMS) of surface electromyography response. The normalisation was achieved by dividing the obtained RMS by the RMS value before thrust application.
Time frame: During the 200N spinal manipulation procedure, assessed up to 2 seconds following thrust onset
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Participants | Right T8 Normalized Root Mean Square (RMS) Value | 3.46 ratio | Standard Error 0.41 |
Primary
Right T8 Normalized Root Mean Square (RMS) Value
Normalized amplitude (RMS) of surface electromyography response. The normalisation was achieved by dividing the obtained RMS by the RMS value before thrust application.
Time frame: During the 150N spinal manipulation procedure, assessed up to 2 seconds following thrust onset
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Participants | Right T8 Normalized Root Mean Square (RMS) Value | 3.51 ratio | Standard Error 0.84 |
Primary
Vertebral Displacement of the Eighth Thoracic Vertebra
Absolute posterior to anterior vertebral displacement during the spinal manipulation in centimeter
Time frame: During the 300N spinal manipulation procedure, assessed up to 2 seconds following thrust onset
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Participants | Vertebral Displacement of the Eighth Thoracic Vertebra | 1.70 cm | Standard Error 0.07 |
Primary
Vertebral Displacement of the Eighth Thoracic Vertebra
Absolute posterior to anterior vertebral displacement during the spinal manipulation in centimeter
Time frame: During the 200N spinal manipulation procedure, assessed up to 2 seconds following thrust onset
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Participants | Vertebral Displacement of the Eighth Thoracic Vertebra | 1.10 cm | Standard Error 0.05 |
Primary
Vertebral Displacement of the Eighth Thoracic Vertebra
Absolute posterior to anterior vertebral displacement during the spinal manipulation in centimeter
Time frame: During the 250N spinal manipulation procedure, assessed up to 2 seconds following thrust onset
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Participants | Vertebral Displacement of the Eighth Thoracic Vertebra | 1.40 cm | Standard Error 0.05 |
Primary
Vertebral Displacement of the Eighth Thoracic Vertebra
Absolute posterior to anterior vertebral displacement during the spinal manipulation in centimeter
Time frame: During the 150N spinal manipulation procedure, assessed up to 2 seconds following thrust onset
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Participants | Vertebral Displacement of the Eighth Thoracic Vertebra | 0.76 cm | Standard Error 0.04 |
Primary
Vertebral Displacement of the Seventh Thoracic Vertebra
Absolute posterior to anterior vertebral displacement during the spinal manipulation in centimeter
Time frame: During the 150N spinal manipulation procedure, assessed up to 2 seconds following thrust onset
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Participants | Vertebral Displacement of the Seventh Thoracic Vertebra | 1.01 cm | Standard Error 0.03 |
Primary
Vertebral Displacement of the Seventh Thoracic Vertebra
Absolute posterior to anterior vertebral displacement during the spinal manipulation in centimeter
Time frame: During the 250N spinal manipulation procedure, assessed up to 2 seconds following thrust onset
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Participants | Vertebral Displacement of the Seventh Thoracic Vertebra | 1.69 cm | Standard Error 0.05 |
Primary
Vertebral Displacement of the Seventh Thoracic Vertebra
Absolute posterior to anterior vertebral displacement during the spinal manipulation in centimeter
Time frame: During the 300N spinal manipulation procedure, assessed up to 2 seconds following thrust onset
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Participants | Vertebral Displacement of the Seventh Thoracic Vertebra | 1.40 cm | Standard Error 0.08 |
Primary
Vertebral Displacement of the Seventh Thoracic Vertebra
Absolute posterior to anterior vertebral displacement during the spinal manipulation in centimeter
Time frame: During the 200N spinal manipulation procedure, assessed up to 2 seconds following thrust onset
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Participants | Vertebral Displacement of the Seventh Thoracic Vertebra | 1.32 cm | Standard Error 0.06 |
Primary
Vertebral Displacement of the Sixth Thoracic Vertebra
Absolute posterior to anterior vertebral displacement during the spinal manipulation in centimeter
Time frame: During the 150N spinal manipulation procedure, assessed up to 2 seconds following thrust onset
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Participants | Vertebral Displacement of the Sixth Thoracic Vertebra | 0.81 cm | Standard Error 0.04 |
Primary
Vertebral Displacement of the Sixth Thoracic Vertebra
Absolute posterior to anterior vertebral displacement during the spinal manipulation in centimeter
Time frame: During the 300N spinal manipulation procedure, assessed up to 2 seconds following thrust onset
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Participants | Vertebral Displacement of the Sixth Thoracic Vertebra | 1.74 cm | Standard Error 0.09 |
Primary
Vertebral Displacement of the Sixth Thoracic Vertebra
Absolute posterior to anterior vertebral displacement during the spinal manipulation in centimeter
Time frame: During the 250N spinal manipulation procedure, assessed up to 2 seconds following thrust onset
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Participants | Vertebral Displacement of the Sixth Thoracic Vertebra | 1.48 cm | Standard Error 0.06 |
Primary
Vertebral Displacement of the Sixth Thoracic Vertebra
Absolute posterior to anterior vertebral displacement during the spinal manipulation in centimeter
Time frame: During the 200N spinal manipulation procedure, assessed up to 2 seconds following thrust onset
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Participants | Vertebral Displacement of the Sixth Thoracic Vertebra | 1.18 cm | Standard Error 0.07 |