Locomotion Strategies of Low Back Pain Patients in a Dynamic Environment

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.


Eligibility Criteria:
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.