Changes in Motor Cortex Following Exercises for Chronic Low Back Pain

Driving Plasticity in the Motor Brain in Chronic Back Pain

The motor cortex of the brain changes following chronic pain and injury, and this is linked to pain-associated changes in motor behaviour. This study aimed to investigate whether therapeutic exercises in patients with chronic pain can induce reorganisation of the motor cortex and restore normal motor behaviour. The investigators hypothesised that motor training can induce reorganisation of the motor cortex and that these changes are related to improved motor behaviour.

Study Overview

• Status: Completed
• Conditions: Chronic Low Back Pain
• Intervention / Treatment: Behavioral: Skilled motor training; Behavioral: Walking exercise

Detailed Description

The sensory and motor systems can reorganize following injury and learning of new motor skills. Recently we observed adaptive changes in motor cortical organization in patients with chronic back pain, which are closely linked to changes in motor behavior. Although pain-related alterations in behavior can be trained and are associated with improved symptoms, it remains unclear whether these meaningful functional outcomes are related to motor cortical reorganization. Here we investigate the effects of two interventions in people with chronic back pain: skilled motor training and a control intervention of self-paced walking exercise. We measured motor cortical excitability (motor threshold (MT)) and organization (center of gravity (CoG) and map volume) of the deep abdominal muscle, transversus abdominis (TrA), using transcranial magnetic stimulation (TMS). In addition, motor behavior of TrA was assessed during single rapid arm movements. The study helps to elucidate the mechanisms of specific motor exercises in chronic back pain management.

• Study Type: Interventional
• Enrollment (Actual): 20
• Phase: Phase 1

Contacts and Locations

Study Locations

• Australia
  • Queensland
    • Brisbane, Queensland, Australia, 4072
      • Centre for Clinical Research Excellence in Spinal Pain, Injury and Health

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 55 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Sustained or episodic non-specific low back pain lasting longer than 3 months

Exclusion Criteria:

• Orthopaedic, neurological, circulatory or respiratory conditions
• History or family history of epilepsy
• Recent or current pregnancies
• Previous surgery to the abdomen or back
• Abdominal or back exercises in the preceding 12 months

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: 1	Behavioral: Skilled motor training; This involves training subjects to independently and cognitively activate the deep abdominal muscles, transversus abdominis, with minimal or no activity in other trunk muscles. The contraction is held for 10 seconds and subjects complete three blocks of ten contractions, twice per day for two weeks. This training protocol is commonly used clinically for people with chronic back pain.
Active Comparator: 2	Behavioral: Walking exercise; The control intervention involves walking exercises for ten minutes, twice per day. Subjects are advised to walk at their own pace with no instructions on activation of specific trunk muscles. The exercise is performed over two weeks.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Motor cortical map and excitability from transcranial magnetic stimulation	Pre and 2 weeks post-intervention

Secondary Outcome Measures

Outcome Measure	Time Frame
Motor activation of the abdominal muscles during functional arm movement task	Pre and 2 weeks post-intervention
Self-reported pain (VAS scale) and functional scale (patient-specific functional scale)	Pre and 2 weeks post-intervention

Collaborators and Investigators

• Sponsor: The University of Queensland
• Investigators: Study Director: Paul W Hodges, MedDr (Neurosci) PhD BPhty, The University of Queensland; Principal Investigator: Henry Tsao, PhD MPhty (Manipulative) BPhty, The University of Queensland

Study record dates

Study Major Dates

• Study Start: October 1, 2006
• Primary Completion (Actual): September 1, 2007
• Study Completion (Actual): September 1, 2007

Study Registration Dates

• First Submitted: March 17, 2009
• First Submitted That Met QC Criteria: March 17, 2009
• First Posted (Estimate): March 18, 2009

Study Record Updates

• Last Update Posted (Estimate): March 18, 2009
• Last Update Submitted That Met QC Criteria: March 17, 2009
• Last Verified: March 1, 2009

More Information

Terms related to this study

• Keywords: low back pain; motor cortex; brain plasticity; motor training
• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Back Pain; Low Back Pain
• Other Study ID Numbers: NHMRC-ID351656; NHMRC-ID401599; PRF-007/06