An observational study in Low Back Pain and Back Pain Lower Back Chronic, sponsored by Hasselt University. Recruiting at 2 sites in Belgium. Open to participants aged 18 Years to 60 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-09-17.
Sponsored by Hasselt University · Observational
Patients with non-specific low back pain will be compared to healthy, age- and sex-matched controls to determine the most discriminating back muscle characteristics and to delineate possible phenotypes of patients with non-specific low back pain showing impaired proprioceptive postural control. Additionally, the group of patients with non-specific low back pain will receive a 16-week, high-load proprioceptive training program. The effects of this training program on the different back muscle characteristics and proprioceptive postural control will be evaluated.
The Back-to-Back study consists of a cross-sectional study and a proof-of-concept study. The cross-sectional study aims to gain more insight into the peripheral underlying mechanisms of impaired proprioceptive postural control in patients with non-specific low back pain. Macroscopic, microscopic, hemodynamic, and electrophysiological characteristics of the lumbar multifidus and erector spinae muscles will be compared between patients with non-specific low back pain and healthy, age- and sex-matched controls. The interrelatedness between these back muscle characteristics and the correlation with proprioceptive postural control will be examined. The most discriminating muscle characteristics will be determined based upon which phenotypes of patients with non-specific low back pain will be delineated. The proof-of-concept study aims to assess the effects of high-load proprioceptive training on back muscle characteristics and proprioceptive postural control in patients with non-specific low back pain.
2,922 studies on the registry are indexed under Low Back Pain; 580 are open to participants now.
This study's planned enrollment of 100 is close to the median of 100 across 481 observational studies indexed under Low Back Pain.
Browse Low Back Pain studies →Hasselt University is the lead sponsor of 204 studies on the registry; 31 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Flemish Brabant
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Patients with non-specific low back pain:
Healthy controls:
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Individuals with chronic non-specific ow back pain
Other: Proprioceptive training
Healthy, age- and sex-matched individuals without low back pain
A physiotherapist tailors the exercises to the patient's functional demands and pain- or fear-inducing activities. Guided by the therapist, patients look for ways to integrate the exercises into their daily life activities. Each week, patients receive feedback from the physiotherapist, and the training program is gradually progressed. The patients are instructed to perform the exercises daily, integrated into their daily activities, hobbies, and work. The program contains: (1) exercises to improve the sense of posture and movement, (2) exercises to correct the reference frame from which patients control posture and movement, (3) muscle control exercises, (4) exercises to increase variability in postures and movement patterns, (5) functionality: patients search for ways to correct and integrate alternative postures and movement patterns into their daily life, (6) high training frequency and high load, (7) focus on sensing, localizing and differentiating, rather than movement control.
Proprioceptive postural control at baseline 1 (t= 0 weeks)
Center-of-pressure displacement in response to ankle and/or back muscle vibration and the Relative Proprioceptive Weighting ratio will be calculated.
Time frame: At baseline 1 (t= 0 weeks)
Proprioceptive postural control at baseline 2 (t= 8 weeks) (only for patients)
Center-of-pressure displacement in response to ankle and/or back muscle vibration and the Relative Proprioceptive Weighting ratio will be calculated.
Time frame: At baseline 2 (t= 8 weeks)
Proprioceptive postural control after 8 weeks of training (t= 16 weeks) (only for patients)
Center-of-pressure displacement in response to ankle and/or back muscle vibration and the Relative Proprioceptive Weighting ratio will be calculated.
Time frame: After 8 weeks of training (t= 16 weeks)
Proprioceptive postural control after 16 weeks of training (t= 24 weeks) (only for patients)
Center-of-pressure displacement in response to ankle and/or back muscle vibration and the Relative Proprioceptive Weighting ratio will be calculated.
Time frame: After 16 weeks of training (t= 24 weeks)
Proprioceptive postural control 16 weeks after the end of training (t= 40 weeks) (only for patients)
Center-of-pressure displacement in response to ankle and/or back muscle vibration and the Relative Proprioceptive Weighting ratio will be calculated.
Time frame: 16 weeks after the end of training (t= 40 weeks)
Macroscopic characteristiscs of the lumbar multifidus and erector spinae muscles at t= 0 weeks (only for healthy controls)
Muscle volume and quality will be measured with 3D freehand ultrasound, muscle cross-sectional area and thickness will be evaluated with 2D ultrasound.
Time frame: At t= 0 weeks
Macroscopic characteristiscs of the lumbar multifidus and erector spinae muscles at baseline 2 (t= 8 weeks) (only for patients)
Muscle volume and quality will be measured with 3D freehand ultrasound, muscle cross-sectional area and thickness will be evaluated with 2D ultrasound.
Time frame: At baseline 2 (t= 8w, 2nd baseline)
Macroscopic characteristics of the lumbar multifidus and erector spinae muscles after 16 weeks of training (t= 24 weeks) (only for patients)
Muscle volume and quality will be measured with 3D freehand ultrasound, muscle cross-sectional area and thickness will be evaluated with 2D ultrasound.
Time frame: After 16 weeks of training (t= 24 weeks)
Macroscopic characteristisc of the lumbar multifidus and erector spinae muscles 16 weeks after the end of training (t= 40 weeks) (only for patients)
Muscle volume and quality will be measured with 3D freehand ultrasound, muscle cross-sectional area and thickness will be evaluated with 2D ultrasound.
Time frame: 16 weeks after the end of training (t= 40 weeks)
Microscopic muscle characteristics of the lumbar multifidus and erector spinae muscles at t= 0 weeks (only for healthy controls)
Fine-needle biopsies of the lumbar multifidus and erector spinae muscles will be acquired.
Time frame: At t= 0 weeks
Microscopic muscle characteristics of the lumbar multifidus and erector spinae muscles at baseline 2 (t= 8 weeks) (only for patients)
Fine-needle biopsies of the lumbar multifidus and erector spinae muscles will be acquired.
Time frame: At baseline 2 (t= 8 weeks)
Microscopic muscle characteristics of the lumbar multifidus and erector spinae muscles after 16 weeks of training (t= 24 weeks) (only for patients)
Fine-needle biopsies of the lumbar multifidus and erector spinae muscles will be acquired.
Time frame: After 16 weeks of training (t= 24 weeks)
Microscopic muscle characteristics of the lumbar multifidus and erector spinae muscles 16 weeks after the end of training (t= 40 weeks) (only for patients)
Fine-needle biopsies of the lumbar multifidus and erector spinae muscles will be acquired.
Time frame: 16 weeks after the end of training (t= 40 weeks)
Hemodynamic muscle characteristics of the lumbar multifidus and erector spinae muscles at baseline 1 (t= 0 weeks)
The Tissue Oxygenation Index will be recorded continuously with near-infrared spectroscopy during different functional postures (prone lying, usual sitting, usual standing, standing with the trunk bent 25° forward).
Time frame: At baseline 1 (t= 0 weeks)
Hemodynamic muscle characteristics of the lumbar multifidus and erector spinae muscles at baseline 2 (t= 8 weeks) (only for patients)
The Tissue Oxygenation Index will be recorded continuously with near-infrared spectroscopy during different functional postures (prone lying, usual sitting, usual standing, standing with the trunk bent 25° forward).
Time frame: At baseline 2 (t= 8 weeks)
Hemodynamic muscle characteristics of the lumbar multifidus and erector spinae muscles after 8 weeks of training (t= 16 weeks) (only for patients)
The Tissue Oxygenation Index will be recorded continuously with near-infrared spectroscopy during different functional postures (prone lying, usual sitting, usual standing, standing with the trunk bent 25° forward).
Time frame: After 8 weeks of training (t= 16 weeks)
Hemodynamic muscle characteristics of the lumbar multifidus and erector spinae muscles after 16 weeks of training (t= 24 weeks) (only for patients)
The Tissue Oxygenation Index will be recorded continuously with near-infrared spectroscopy during different functional postures (prone lying, usual sitting, usual standing, standing with the trunk bent 25° forward).
Time frame: After 16 weeks of training (t= 24 weeks)
Hemodynamic muscle characteristics of the lumbar multifidus and erector spinae muscles 16 weeks after the end of training (t= 40 weeks) (only for patients)
The Tissue Oxygenation Index will be recorded continuously with near-infrared spectroscopy during different functional postures (prone lying, usual sitting, usual standing, standing with the trunk bent 25° forward).
Time frame: 16 weeks after the end of training (t= 40 weeks)
Electrophysiological muscle characteristics of the lumbar multifidus and erector spinae at baseline 1 (t= 0 weeks)
Muscle activitation levels and patterns will be measured with surface electromyography during different functional postures (prone lying, usual sitting, usual standing, standing with the trunk bent 25° forward).
Time frame: At baseline 1 (t= 0 weeks)
Electrophysiological muscle characteristics of the lumbar multifidus and erector spinae at baseline 2 (t= 8 weeks) (only for patients)
Muscle activitation levels and patterns will be measured with surface electromyography during different functional postures (prone lying, usual sitting, usual standing, standing with the trunk bent 25° forward).
Time frame: At baseline 2 (t= 8 weeks)
Electrophysiological muscle characteristics of the lumbar multifidus and erector spinae after 8 weeks of training (t= 16 weeks) (only for patients)
Muscle activitation levels and patterns will be measured with surface electromyography during different functional postures (prone lying, usual sitting, usual standing, standing with the trunk bent 25° forward).
Time frame: After 8 weeks of training (t= 16 weeks)
Electrophysiological muscle characteristics of the lumbar multifidus and erector spinae after 16 weeks of training (t= 24 weeks) (only for patients)
Muscle activitation levels and patterns will be measured with surface electromyography during different functional postures (prone lying, usual sitting, usual standing, standing with the trunk bent 25° forward).
Time frame: After 16 weeks of training (t= 24 weeks)
Electrophysiological muscle characteristics of the lumbar multifidus and erector spinae 16 weeks after the end of training (t= 40 weeks) (only for patients)
Muscle activitation levels and patterns will be measured with surface electromyography during different functional postures (prone lying, usual sitting, usual standing, standing with the trunk bent 25° forward).
Time frame: 16 weeks after the end of training (t= 40 weeks)
Disability due to low back pain
Participants will be asked to complete the Modified Low Back Pain Disability Questionnaire.
Time frame: Controls: once, immediately after inclusion, Patients: 5 times, immediately after inclusion (t= 0w), after 8 weeks (t= 8w, 2nd baseline), after 8 weeks of training (t= 16w), after 16 weeks of training (t= 24w), 16 weeks after the end of training (t= 40w)
Risk for future work disability due to low back pain
Participants will be asked to complete the short version of the Örebro Musculoskeletal Pain Screening Questionnaire
Time frame: Controls: once, immediately after inclusion, Patients: 5 times, immediately after inclusion (t= 0w), after 8 weeks (t= 8w, 2nd baseline), after 8 weeks of training (t= 16w), after 16 weeks of training (t= 24w), 16 weeks after the end of training (t= 40w)
Pain-related fear of movement
Participants will be asked to complete the Tampa Scale for Kinesiophobia.
Time frame: Controls: once, immediately after inclusion, Patients: 5 times, immediately after inclusion (t= 0w), after 8 weeks (t= 8w, 2nd baseline), after 8 weeks of training (t= 16w), after 16 weeks of training (t= 24w), 16 weeks after the end of training (t= 40w)
Fear-avoidance beliefs about physical activity and work
Participants will be asked to complete the Fear-Avoidance Beliefs Questionnaire.
Time frame: Controls: once, immediately after inclusion, Patients: 5 times, immediately after inclusion (t= 0w), after 8 weeks (t= 8w, 2nd baseline), after 8 weeks of training (t= 16w), after 16 weeks of training (t= 24w), 16 weeks after the end of training (t= 40w)
Pain catastrophizing
Participants will be asked to complete the Pain Catastrophizing Scale.
Time frame: Controls: once, immediately after inclusion, Patients: 5 times, immediately after inclusion (t= 0w), after 8 weeks (t= 8w, 2nd baseline), after 8 weeks of training (t= 16w), after 16 weeks of training (t= 24w), 16 weeks after the end of training (t= 40w)
Anxiety and depression
Participants will be asked to complete the Hospital Anxiety and Depression Scale.
Time frame: Controls: once, immediately after inclusion, Patients: 5 times, immediately after inclusion (t= 0w), after 8 weeks (t= 8w, 2nd baseline), after 8 weeks of training (t= 16w), after 16 weeks of training (t= 24w), 16 weeks after the end of training (t= 40w)
Habitual physical activity
Participants will be asked to complete the Baecke Questionnaire.
Time frame: Controls: once, immediately after inclusion, Patients: 5 times, immediately after inclusion (t= 0w), after 8 weeks (t= 8w, 2nd baseline), after 8 weeks of training (t= 16w), after 16 weeks of training (t= 24w), 16 weeks after the end of training (t= 40w)
Age
Age (years) will be recorded.
Time frame: Immediately after inclusion
Sex (male/female)
Sex will be recorded.
Time frame: Immediately after inclusion
Highest level of education
Highest level of education will be recorded.
Time frame: Immediately after inclusion
Current employment status
Current employment status will be recorded.
Time frame: Immediately after inclusion
Body weight (kg)
Body weight (kg) will be recorded.
Time frame: Immediately after inclusion
Height (cm)
Height (cm) will be recorded.
Time frame: Immediately after inclusion
Handedness (left, right)
Handedness will be recorded.
Time frame: Immediately after inclusion
Current pain intensity (only for patients)
Patients will be asked to rate the current intensity of pain in their lower back (and leg if present) on a Numerical Rating Scale with anchors 0= no pain and 10= worst pain.
Time frame: Immediately after inclusion
Duration of low back pain (only for patients)
The duration of low back pain (months) will be recorded.
Time frame: Immediately after inclusion
Medication use (only for patients)
Medication use will be recorded.
Time frame: Immediately after inclusion
Plan to share: No
No publications or documents are linked to this record.
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
Contact study teamGet an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.