The METRIC Study Protocol

Université du Québec à Trois-Rivières

Status: Enrolling

Conditions: Chronic Low-back Pain

Treatments: Procedure: lumbar spinal manipulative therapy; Procedure: full spine spinal manipulative therapy; Procedure: sham spinal manipulative therapy

Study type: Interventional

Funder types: Other

Identifiers

NCT05986370

METRIC

Details and patient eligibility

About

The goal of this clinical trial is to test the effects of spinal manipulative therapy in individuals with chronic primary low back pain and determine the neurophysiological mechanisms underlying pain relief. The main questions it aims to answer are: • Is pain relief produced by spinal manipulative therapy in patients with chronic primary low back pain caused by a reduction of C-fiber-related nociceptive processing? • Are these effects greater when spinal manipulative therapy is applied to the whole spine where it is clinically indicated compared with lumbar spine only? • Are these effects greater after 36 treatments over 3 months compared with 12 treatments over 1 month. Participants will receive spinal manipulative therapy (all clinically indicated spine segments or back only) or a control intervention. A group of healthy volunteers will be recruited to assess secondary outcome measures over the same time period, as reference data for comparisons. Researchers will compare the two groups receiving spinal manipulative therapy to the group receiving the control intervention to see if clinical pain relief and the reduction of temporal summation of second pain (produced experimentally) is significantly greater with spinal manipulative therapy.

Enrollment: 112 estimated patients

Sex: All

Ages: 18 to 60 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Duration of current low back pain (LBP) episode ≥ 6 months;
• Average LBP intensity during the last 7 days ≥ 3/10;
• (For healthy volunteers only) To be of the same sex and age (± 1 year) as a participant with low back pain.

Exclusion criteria

• Diagnosis of back conditions other than chronic primary LBP e.g., failed back surgery syndrome, spondylosis, spondylolisthesis, spinal stenosis, herniated disc, infection, etc.;
• Presence of pain in another body location that is more severe than the pain in the lower back;
• Presence of a neurological deficit i.e., sensation loss, muscle weakness, decreased deep tendon reflexes;
• Presence of contraindications to spinal manipulative therapy e.g., recent fracture, history of spinal surgery, cauda equina syndrome, inflammatory arthritis, taking anticoagulant medication, active cancer, moderate to severe osteoporosis, abdominal aortic aneurysm;
• Underwent surgery in the last 3 months;
• Pregnancy, ≤ 3 months post-partum or planning to get pregnant in the next 12 months;
• History of spinal manipulative therapy in the past 12 months;
• Scoliosis ≥ 20°;
• BMI ≥ 40;
• Insufficient language skills in French to complete the questionnaires;
• Open or pending litigation for LBP or seeking/receiving disability compensation;
• Diagnosis of an illness affecting the sensorimotor functions e.g., diabetes, multiple sclerosis, amyotrophic lateral sclerosis;
• Diagnosis of mental health disorders (with the exception of anxiety and depression);
• Current drug or alcohol dependence;
• Skin of type I on the Fitzpatrick scale;
• (For healthy volunteers only) Regular use of pain medication or usage in the 48 h prior to data collection;
• (For healthy volunteers only) History of chronic pain;
• (For healthy volunteers only) Acute pain on the days of data collection.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Triple Blind

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112 participants in 4 patient groups

lumbar spinal manipulative therapy

Experimental group

Description:

Participants will receive spinal manipulative therapy (SMT) exclusively at dysfunctional lumbar segments. Participants will receive 36 SMT sessions over 12 weeks, 3 times per week, each session lasting ≈15 min. Spinal manipulation will be performed using the diversified technique. For each treatment, the SMT provider will perform two spinal manipulations, one on each side of the most painful lumbar vertebra. During spinal manipulations, participants will lay on their side and they will be instructed to inhale and exhale fully before each thrust.

Treatment:

Procedure: lumbar spinal manipulative therapy

full spine spinal manipulative therapy

Experimental group

Description:

Participants will receive spinal manipulative therapy (SMT) at dysfunctional spinal segments in the lumbar AND other spine regions. Participants will receive 36 spinal manipulative therapy (SMT) sessions over 12 weeks, 3 times per week, each session lasting ≈15 min. Spinal manipulation will be performed using the diversified technique. For each treatment, the SMT provider will perform a minimum of two spinal manipulations, one on each side of the most painful lumbar vertebra. Spinal manipulation will also be delivered at other dysfunctional spinal segments, based on clinical examination. During spinal manipulations, participants will lay prone, supine or on their side and they will be instructed to inhale and exhale fully before each thrust.

Treatment:

Procedure: full spine spinal manipulative therapy

sham spinal manipulative therapy

Sham Comparator group

Description:

Participants will receive 36 sham SMT sessions (3x/week for 12 weeks, each session ≈15 min). This will target dysfunctional segments in the lumbar and other spine regions. Three maneuvers will be used: * Ventral decubitus: 1 to 5 light and brief manual contacts (≈ 20 N and 5 s) will be applied and quickly released over the spinous process of dysfunctional vertebrae identified during clinical examination. * Dorsal decubitus: sections of the treatment table will be slightly raised or lowered (≈ 5 cm) and their lower limbs' position changed once or twice e.g., knees bent, hips internally or externally rotated. Each position maintained during ≈ 30 s. * Lateral decubitus: 1 to 5 impulses at the lowest setting of the Activator V instrument (Activator Methods Int. Ltd., Phoenix, Arizona, USA) will be applied on their gluteus and quadratus lumborum muscles. The position of the instrument will change after each impulse.

Treatment:

Procedure: sham spinal manipulative therapy

no intervention

No Intervention group

Description:

This fourth arm will comprise healthy volunteers (age/sex-matched to the participants in the test intervention - lumbar group) who will not receive any intervention. The main purpose of this fourth group is to provide reference values to interpret some results obtained in participants with chronic primary low back pain.