Locomotion Strategies of Low Back Pain Patients in a Dynamic Environment

Study Overview
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Brief Summary
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The biomechanical parameters studied in non-specific chronic low back pain patients in a locomotion task have so far focused on straight line walking. Although locomotion is primarily an automated action composed of repetitive patterns allowing movement from one place to another, walkers must respond to the environmental demands.These modifications show a flexible and adaptive approach to the constraints of the environment. In this study, the investigators are particularly interested in a task of crossing between two pedestrians, which is a standardised task that has shown its interest in the study of perceptual-motor co-ordination. In particular, it allows to study the mutual adaptation of speed and orientation between the two walkers.

Official Title
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Collision Avoidance Behavior Between Walkers: Locomotion Strategies of Patients With Chronic Non-Specific Low Back Pain

Conditions
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Chronic Low-back Pain, Walking

Intervention / Treatment
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* Behavioral: Quantified analysis of walking during a crossing task between two walkers


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria Non Specific Chronic Low Back Pain patients: Participants must have pain located between the thoracolumbar hinge and the lower gluteal fold, with or without pain in either leg. This pain must have been present for more than 12 weeks, on a daily or almost daily basis (at least 4 days out of 7) Participants must not be on any treatment or have been on stable analgesic treatment for at least 2 weeks prior to inclusion Participants must speak, read and understand French Participants must be between 18 and 65 years of age Participants must be able to understand simple commands and experimental instructions Participants must have normal or corrected vision Participants must have given informed consent to participate in the study Participants must be enrolled in or receiving social security benefits Exclusion Criteria Non Specific Chronic Low Back Pain patients: Participants must not be pregnant or nursing mothers. Participants must not have cognitive or psychological impairments that are incompatible with compliance and/or understanding of the protocol Participants must not be unable to understand informed consent, or be under guardianship or conservatorship Subjects must not already be participating in another research protocol involving the human subject or in parallel Participants must not be persons deprived of liberty by judicial or administrative decision Participants must not be under psychiatric care The participants must not present neurological signs evoking a neurodegenerative disease responsible for walking disorders (parkinsonian syndrome, ...) The participants must not present warning signs (red flags) pointing to an underlying pathology requiring specific and/or urgent care such as Ongoing litigation following a work-related accident Pain related to a cancer diagnosis Associated spinal cord symptoms (pyramidal signs, coordination disorders, motor or sensory deficits, sphincter disorders, etc.) Pain following an infection (night sweats, fever, chills, intravenous drug abuse, immunodeficiency, recent surgery, urinary or skin infection, etc.) Recent or pathological fractures (traffic accidents, history of osteoporosis, chronic use of corticosteroids, advanced age, unexplained weight loss, fatigue, history of cancer, etc. ) Vascular problems (cold feet, decreased peripheral arterial pulse, etc.) Inclusion and Exclusion Criteria of control group : Participants strictly meet the same inclusion and non-inclusion criteria as NSCLBP patients, but must not have ongoing chronic pain or a history of significant chronic pain (≥ 4/10 for at least 6 months). They are matched for age and gender. They must not have any pathologies that affect walking or posture. These individuals must be able to perform the studied movements without the appearance of discomfort or exaggerated fatigue.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Non-Specific Low Back Pain patients<br>Participants must have pain located between the thoracolumbar hinge and the lower gluteal fold, with or without pain in either leg, present for more than 12 weeks, on a daily or almost daily basis (at least 4 days out of 7). | Behavioral: Quantified analysis of walking during a crossing task between two walkers<br>* Functional test that reproduce a task of daily living.<br>|
| Control group<br>Participant with no current or past chronic pain | Behavioral: Quantified analysis of walking during a crossing task between two walkers<br>* Functional test that reproduce a task of daily living.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Threshold for motion adaptation | Thresholds of adaptation to movement will be identified by comparing the minimum crossing distance and the minimum predicted distance of crossing at the time the walkers first see each other. | Clinical assessment at base line | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Walking speed | Analysis of the walking speed of each walker for the control tests, i.e. where the walker has not encountered another walker. | Clinical assessment at base line | 
| Inversion of crossing order | mpd(t) was assigned according to the final crossing order between two walkers in such a way that allowed for a positive mpd (tcross). In doing so, a positive mpd(tsee) suggests that crossing order was preserved along the entire interaction. Alternatively, a negative mpd (tsee) is the result of an inversion in crossing order between the two walkers. | Clinical assessment at base line | 
| Contribution to collision avoidance | During the interaction period, a cumulative contribution must be made by both walkers to avoid a collision. Analysis of the contribution of each walker (speed and orientation). | Clinical assessment at base line | 
| Minimum Predicted Distance | Minimum Predicted Distance (mpd) represents the theoretical crossing distance between the future positions of the participants, based on a linear extrapolation of their trajectory given their current position and speed at time (t). Any variation in mpd(t) indicates that a movement adaptation to avoid a collision has taken place between two walkers. | Clinical assessment at base line | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Low Back Pain, Psychomotor Performance / physiology, Walking / physiology*, Adult, Humans, Motion Perception / physiology*