Investigating the Hypoalgesic Effects of Manipulative Therapy Using Pain Conditioning and Expectations in Low Back Pain

NCT ID: NCT05202704

Last Updated: 2023-03-23

Basic Information

• Recruitment Status: UNKNOWN
• Clinical Phase: NA
• Total Enrollment: 264 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2022-02-20
• Study Completion Date: 2024-03-10

Brief Summary

The objective of this study will be to identify whether a conditioning procedure by the surreptitious downgrade of a noxious stimulus intensity associated with induced positive expectations about treatment will result in greater hypoalgesic effects when compared to positive verbal suggestions (positive expectation induction) alone regarding the effects of spinal manipulative therapy intervention in patients with CLBP. This study will enroll 264 individuals with CLBP aged between 18 and 60 years. Spinal Manipulative Therapy in the lumbar spine will be administered to all participants during 5 sessions.

First assessment session - participants will be submitted to a quantitative sensory testing (QST) to determine the heat pain threshold (calibration test) to run the conditioning procedure. Afterward, participants will be allocated by a blinded researcher into the following subgroups: hidden conditioning + positive expectation (G1); positive expectation alone (G2) and a group submitted to neutral expectations (G3) about the treatment.

First treatment session - Firstly, participants will receive instructions with the aim to induce positive (or neutral) expectations by means of a workshop. Secondly, all the participants will be submitted again to the pre-conditioning test, using the more intense pain stimulus obtained in the calibration test, then patients will be assessed regarding pain intensity and finally submitted to the manipulative therapy. At the end of the first treatment session, the conditioning test will be repeated, but the heat pain threshold of the hidden conditioning group (G1) will be surreptitiously downgraded (from intense pain stimulus to moderate pain stimulus) as a means of conditioning patients to believe that manipulative therapy promoted pain relief. Pain intensity will be assessed again to confirm a decrease in pain intensity.

Outcomes will be assessed three times: immediately after the five therapy sessions, one month later, and three months later. The primary outcomes assessed will be pain intensity and global perceived effect of improvement. The secondary outcome will be low back pain disability.

Detailed Description

Background: The term "contextual effect" has been used to reinforce the view that the placebo effect should be understood as an effect related to the therapeutic context, and not restricted to the use of inert treatments. Thus, the placebo effect is inherent to any therapeutic context and also can be used to enhance the effects of treatment with active components. There is evidence of the effectiveness of manipulative therapy in the treatment of chronic low back pain (CLBP), however, for most physical therapy interventions, its effect is small. Thus, strategies to enhance the effects of this therapy, such as through the use of context factors, may contribute to better therapeutic outcomes. The literature describes conditioning or positive induced expectation models to favor the placebo effect. Although some previous studies have shown that expectation alone or associated with conditioning procedures may intensify the hypoalgesic effects of therapies, no previous work has verified the isolated or associated hypoalgesic effect of conditioning and induction of expectancy on treatment in patients with CLBP undergoing manipulative therapy. Thus, the objective of this study will be to identify whether a conditioning procedure through surreptitious downgrade of nociceptive stimulus intensity associated with positive induced expectation about treatment will result in greater hypoalgesic effects when compared to positive verbal suggestions (expectations) induced or expectation alone regarding the effects of the Spinal Manipulative Therapy intervention in patients with CLBP. Methods: it will be a randomized controlled trial with a blinded assessor. It will be investigated the effect of the use of a hidden conditioning procedure and the induction of positive expectations on pain intensity after the administration of a manipulative therapy approach. We will enroll 264 patients with nonspecific CLBP aged 18 to 60 years will participate in this study. The sample size calculation was based on a minimal difference between groups of 2 units on pain intensity and overall perception of improvement (primary outcomes). All patients will undergo 5 sessions of Manipulative Therapy in the lumbar spine, except the no-treatment group (G3). In the first session, patients will be subjected to the inclusion and exclusion criteria and the calibration test (quantitative sensory testing) to determine the intense, moderate and weak thermal pain threshold, using the Q-sense equipment, for the conditioning procedure.

In the second session (beginning of the treatment), firstly the patients will be randomized to one of the three groups by a blinded assessor: hidden conditioning + positive expectations (G1) group; positive expectations group (G2) and neutral expectation group (G3). Following, participants will receive specific instructions to induce expectation in G1 and G2, and for G3, neutral instructions.

In the first treatment session - patients will receive the pre-conditioning test (heat pain), then they will be submitted to the manipulative therapy and again undergo the heat-conditioning post-testing. However, G1 will receive hidden conditioning (surreptitiously downgrade of noxious stimulus intensity from intense to moderate pain) to reinforce the association between manipulative therapy and pain intensity reduction. Pain intensity will be assessed just after the conditioning procedures as a manipulation check of the downgrading of the noxious stimulus.

The main hypothesis of this study is that the group undergoing hidden conditioning associated with positive induced expectation will have a higher hypoalgesic effect than the other groups immediately post-treatment.

Outcomes will be assessed three times: immediately after the five therapy sessions, one month later, and three months later. The primary outcomes assessed will be pain intensity and global perceived effect of improvement. The secondary outcome will be low back pain disability.

Conditions

Chronic Low Back Pain

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: DOUBLE

Study Groups

Experimental: Hidden conditioning procedure + Positive Expectation

Patients with chronic low back pain will receive verbal delivered positive instructions regarding manipulative therapy. Then, after the spinal manipulative therapy they will be submitted to a hidden conditioning procedure in which the pain threshold will be surreptitiously downgrade to conditioning pain decrease to manipulative therapy (G1).

Group Type: EXPERIMENTAL

Procedure/Surgery: Experimental: Hidden conditioning + Positive Expectation

Intervention Type: PROCEDURE

Patients will be submitted to quantitative sensory testing to determine different thresholds of noxious heat pain stimulus (intense, moderate or weak). Afterward, participants will receive instructions with the aim to induce positive expectations about the treatment by means of a workshop. Immediately after the first session of manipulative therapy, participants will be submitted again to the QST but now the heat pain threshold of the hidden conditioning group will be surreptitiously downgraded (the intense noxious stimulus will be downgraded to the moderate stimulus - individually obtained during the QST) as a mean to conditioning patients to believe that spinal manipulative therapy promoted pain relief. Patients will be invited to report the pain intensity perceived just after the QST (second test - conditioning procedure). The objective of questioning the pain intensity after the conditioning test is a procedure check to ensure that the conditioning procedure worked.

Spinal Manipulative Therapy

Intervention Type: PROCEDURE

All the groups recruited in the study will receive five sessions of Spinal Manipulative Therapy. The intervention will be performed with the patient in the supine position. The clinician-researcher will passively lean over the patient to the side to be manipulated and ask the patient to place their hands behind their head. The researcher will then passively rotate the patient on the side to be manipulated and perform a posterior and inferior thrust on the opposite anterosuperior spine. The patients will receive 4 maneuvers (twice towards right side and twice towards left side).

Active Comparator: Positive expectations

Patients with chronic low back pain will receive verbal delivered positive instructions regarding spinal manipulative therapy (G2) before the administration of a spinal manipulative therapy approach.

Group Type: ACTIVE_COMPARATOR

Procedure/Surgery: Active Comparator: Positive Expectation

Intervention Type: PROCEDURE

Patients in this group will be submitted to a quantitative sensory testing to determine different thresholds of noxious heat pain stimulus (intense, moderate or weak). Afterward, participants will receive instructions with the aim to induce positive expectation about the treatment by means of a workshop. Immediately after the first session of spinal manipulative therapy, participants will be submitted again to the QST (without downgrading of the intense noxious heat stimulus). Patients will be invited to report the pain intensity perceived during the QST after the intervention. The objective of questioning the pain intensity in this group is a procedure check - to investigate whether the positive instructions will show any effect.

Spinal Manipulative Therapy

Intervention Type: PROCEDURE

All the groups recruited in the study will receive five sessions of Spinal Manipulative Therapy. The intervention will be performed with the patient in the supine position. The clinician-researcher will passively lean over the patient to the side to be manipulated and ask the patient to place their hands behind their head. The researcher will then passively rotate the patient on the side to be manipulated and perform a posterior and inferior thrust on the opposite anterosuperior spine. The patients will receive 4 maneuvers (twice towards right side and twice towards left side).

Active Comparator: Neutral Expectations

Patients with chronic low back pain will receive verbal delivered neutral instructions regarding spinal manipulative therapy (G3) before the administration of a spinal manipulative therapy approach.

Group Type: ACTIVE_COMPARATOR

Procedure/Surgery: Active Comparator: Neutral Expectation

Intervention Type: PROCEDURE

Patients in this group will be submitted to a quantitative sensory testing to determine different thresholds of noxious heat pain stimulus (intense, moderate or weak). Afterward, participants will receive instructions with the aim to induce neutral expectation about the treatment by means of a workshop. Immediately after the first session of spinal manipulative therapy, participants will be submitted again to the QST (without downgrading of the intense noxious heat stimulus). Patients will be invited to report the pain intensity perceived during the QST after the intervention. The objective of questioning the pain intensity in this group is a procedure check - to investigate/confirm the effect of neutral instructions.

Spinal Manipulative Therapy

Intervention Type: PROCEDURE

All the groups recruited in the study will receive five sessions of Spinal Manipulative Therapy. The intervention will be performed with the patient in the supine position. The clinician-researcher will passively lean over the patient to the side to be manipulated and ask the patient to place their hands behind their head. The researcher will then passively rotate the patient on the side to be manipulated and perform a posterior and inferior thrust on the opposite anterosuperior spine. The patients will receive 4 maneuvers (twice towards right side and twice towards left side).

Interventions

Procedure/Surgery: Experimental: Hidden conditioning + Positive Expectation

Patients will be submitted to quantitative sensory testing to determine different thresholds of noxious heat pain stimulus (intense, moderate or weak). Afterward, participants will receive instructions with the aim to induce positive expectations about the treatment by means of a workshop. Immediately after the first session of manipulative therapy, participants will be submitted again to the QST but now the heat pain threshold of the hidden conditioning group will be surreptitiously downgraded (the intense noxious stimulus will be downgraded to the moderate stimulus - individually obtained during the QST) as a mean to conditioning patients to believe that spinal manipulative therapy promoted pain relief. Patients will be invited to report the pain intensity perceived just after the QST (second test - conditioning procedure). The objective of questioning the pain intensity after the conditioning test is a procedure check to ensure that the conditioning procedure worked.

Intervention Type: PROCEDURE

Procedure/Surgery: Active Comparator: Positive Expectation

Patients in this group will be submitted to a quantitative sensory testing to determine different thresholds of noxious heat pain stimulus (intense, moderate or weak). Afterward, participants will receive instructions with the aim to induce positive expectation about the treatment by means of a workshop. Immediately after the first session of spinal manipulative therapy, participants will be submitted again to the QST (without downgrading of the intense noxious heat stimulus). Patients will be invited to report the pain intensity perceived during the QST after the intervention. The objective of questioning the pain intensity in this group is a procedure check - to investigate whether the positive instructions will show any effect.

Intervention Type: PROCEDURE

Procedure/Surgery: Active Comparator: Neutral Expectation

Patients in this group will be submitted to a quantitative sensory testing to determine different thresholds of noxious heat pain stimulus (intense, moderate or weak). Afterward, participants will receive instructions with the aim to induce neutral expectation about the treatment by means of a workshop. Immediately after the first session of spinal manipulative therapy, participants will be submitted again to the QST (without downgrading of the intense noxious heat stimulus). Patients will be invited to report the pain intensity perceived during the QST after the intervention. The objective of questioning the pain intensity in this group is a procedure check - to investigate/confirm the effect of neutral instructions.

Intervention Type: PROCEDURE

Spinal Manipulative Therapy

All the groups recruited in the study will receive five sessions of Spinal Manipulative Therapy. The intervention will be performed with the patient in the supine position. The clinician-researcher will passively lean over the patient to the side to be manipulated and ask the patient to place their hands behind their head. The researcher will then passively rotate the patient on the side to be manipulated and perform a posterior and inferior thrust on the opposite anterosuperior spine. The patients will receive 4 maneuvers (twice towards right side and twice towards left side).

Intervention Type: PROCEDURE

Eligibility Criteria

Inclusion Criteria

1. Patients who report non-specific CLBP (in which the specific nociceptive source cannot be identified, confirmed by a medical assessment) for at least three months duration;

2. Age ranged from 18 years to 60 years

3. Baseline pain intensity score ≥3 on a Numeric Pain Rating Scale (NPRS) (because of the measurement error > 2 reported for the NPRS);

4. Score greater than 14% on the Oswestry Disability Index (ODI) (to surpass the smallest detectable change of the ODI total score

5. Patients able to speak and understand Portuguese well to fill out the questionnaires.

Patients will be excluded if they met any of the following criteria:

1. Previous poor experiences with SMT through the application of a brief screening questionnaire

2. Pregnancy

3. Specific low back pain disorders like radiculopathy or lumbar stenosis or chronic degenerative disorders, i.e., uncontrolled cardiovascular, metabolic, or systemic diseases, neurological or psychiatric diseases, and stroke sequelae

4. Undergoing other therapeutic interventions for chronic pain and low back pain (including surgeries) in the last 3 months

5. Presence of contraindications to SMT

6. Patients who reach the upper limit of 50ºC, which is the maximum temperature provided by the Q-sense equipment described in the Medoc, Israel website

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 60 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Fundação de Amparo à Pesquisa do Estado de São Paulo

OTHER_GOV

Sponsor Role: collaborator

Universidade Federal de Sao Carlos

OTHER

Sponsor Role: lead

Responsible Party

Thais Chaves

Associate Professor

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Thais Chaves, PhD

Role: STUDY_CHAIR

Federal University of São Carlos - UFSCar

Locations

Unidade Saúde Escola - USE

São Carlos, São Paulo, Brazil

Site Status: RECRUITING

Countries

Brazil

Central Contacts

Thaís C Chaves, PhD

Role: CONTACT

thaischaves@ufscar.br

+55 (16) 3602-4694

Helen N Carrer, PhD

Role: CONTACT

helencnogueira@yahoo.com.br

+55 (16) 98163-8793

Facility Contacts

Helen Nogueira Carrer, PhD

Role: primary

helennogueira@ufscar.br

05516981638793

References

Nogueira Carrer HC, Lima TC, George SZ, Reis FJJD, Dias DLC, Campanha BES, Chaves TC. Investigating the hypoalgesic effects of spinal manipulative therapy using hidden pain conditioning and positive expectation in patients with chronic low back pain: protocol for a randomised controlled trial. BMJ Open. 2023 Apr 12;13(4):e066199. doi: 10.1136/bmjopen-2022-066199.

Reference Type: DERIVED

PMID: 37045570 (View on PubMed)

Other Identifiers

52925921.5.0000.5504

Identifier Type: -

Identifier Source: org_study_id