Does Motor Control Exercise Restore Normal Morphology of Lumbar Multifidus Muscle in People with Low Back Pain? - A Systematic Review

Physical therapy for acute and sub-acute low back pain: A systematic review and expert consensus

OBJECTIVE

To review the effectiveness of different physical therapies for acute and sub-acute low back pain supported by evidence, and create clinical recommendations and expert consensus for physiotherapists on clinical prescriptions.

DATA SOURCES

A systematic search was conducted in PubMed and the Cochrane Library for studies published within the previous 15 years.

REVIEW METHODS

Systematic review and meta-analysis, randomized controlled trials assessing patients with acute and sub-acute low back pain were included. Two reviewers independently screened relevant studies using the same inclusion criteria. The Physiotherapy Evidence Database and the Assessment of Multiple Systematic Reviews tool were used to grade the quality assessment of randomized controlled trials and systematic reviews, respectively. The final recommendation grades were based on the consensus discussion results of the Delphi of 22 international experts.

RESULTS

Twenty-one systematic reviews and 21 randomized controlled trials were included. Spinal manipulative therapy and low-level laser therapy are recommended for acute low back pain. Core stability exercise/motor control, spinal manipulative therapy, and massage can be used to treat sub-acute low back pain.

CONCLUSIONS

The consensus statements provided medical staff with appliable recommendations of physical therapy for acute and sub-acute low back pain. This consensus statement will require regular updates after 5-10 years.

Targeted multifidus muscle activation reduces fibrosis of multifidus muscle following intervertebral disc injury

PURPOSE

Aerobic exercise produces beneficial outcomes in patients with low back pain and partially attenuates the fibrotic changes to the multifidus in a model of intervertebral disc (IVD) degeneration. More targeted exercise might be required to fully attenuate these fibrotic alterations. This study aimed to investigate whether activation of the multifidus induced by neurostimulation could reduce fibrosis of the multifidus in a model of IVD degeneration in sheep.

METHODS

IVD degeneration was induced in 18 merino sheep via a partial thickness unilateral annulus fibrosus lesion to the L1/2 and L3/4 IVDs. All sheep received an implantable neurostimulation device that provides stimulation of the L2 medial branch of the dorsal ramus. Three months after surgery, the animals were assigned to Injury or Activated groups. Activated animals received neurostimulation and the Injury group received no stimulation. Six months after surgery, the multifidus was harvested at L2 and L4. Van Gieson's, Sirius Red and immunofluorescence staining for Collagen-I and -III and quantitative PCR was used to examine fibrosis. Muscle harvested from a previous study without IVD injury was used as a control.

RESULTS

Neurostimulation of the multifidus attenuated IVD degeneration dependent increases in the connective tissue, including Collagen-I but not Collagen-III, compared to the Injury group at L4. No measures of the multifidus muscle at L2, which received no stimulation, differed between the Injury and Activated groups.

CONCLUSIONS

These data reveal that targeted activation of the multifidus muscle attenuates IVD degeneration dependent fibrotic alterations to the multifidus.

The efficacy and safety of oral antibiotic treatment in patients with chronic low back pain and Modic changes: A systematic review and meta-analysis

Background

This systematic review and meta-analysis aimed to summarize evidence regarding the effectiveness and safety of oral antibiotic intervention for chronic low back pain (CLBP) patients with/without type-1 Modic changes (MC1).

Methods

AMED, CINAHL, Cochrane Library, Embase, and Medline were searched from inception to March 3, 2023. Randomized controlled trials (RCTs) or non-RCTs that investigated the effectiveness or safety of oral antibiotics in treating CLBP patients were eligible for inclusion. Two independent reviewers screened abstracts, full-text articles, and extracted data. The methodological quality of each included article were evaluated by RoB2 and NIH quality assessment tools. The quality of evidence was appraised by GRADE. Meta-analyses were performed, where applicable. A subgroup analysis was conducted to evaluate the RCTs and case series separately, and to evaluate the effect of removing a low-quality RCT.

Results

Three RCTs and four case series were included. All Amoxicillin-clavulanate/Amoxicillin treatments lasted for approximately 3 months. Moderate- and low-quality evidence suggested that antibiotic was significantly better than placebo in improving disability and quality of life in CLBP patients with MC1 at 12-month follow-up, respectively. Low-quality evidence from meta-analyses of RCTs showed that oral antibiotic was significantly better than placebo in improving pain and disability in CLBP patients with MC1 immediately post-treatment. Very low-quality evidence from the case series suggested that oral Amoxicillin-clavulanate significantly improved LBP/leg pain, and LBP-related disability. Conversely, low-quality evidence found that oral Amoxicillin alone was not significantly better than placebo in improving global perceived health in patients with CLBP at the 12-month follow-up. Additionally, oral antibiotic users had significantly more adverse effects than placebo users.

Conclusions

Although oral antibiotics were statistically superior to placebo in reducing LBP-related disability in patients with CLBP and concomitant MC1, its clinical significance remains uncertain. Future large-scale high-quality RCTs are warranted to validate the effectiveness of antibiotics in individuals with CLBP.

Multifidus dysfunction and restorative neurostimulation: a scoping review

OBJECTIVE

Chronic low back pain (CLBP) is multifactorial in nature, with recent research highlighting the role of multifidus dysfunction in a subset of nonspecific CLBP. This review aimed to provide a foundational reference that elucidates the pathophysiological cascade of multifidus dysfunction, how it contrasts with other CLBP etiologies and the role of restorative neurostimulation.

METHODS

A scoping review of the literature.

RESULTS

In total, 194 articles were included, and findings were presented to highlight emerging principles related to multifidus dysfunction and restorative neurostimulation. Multifidus dysfunction is diagnosed by a history of mechanical, axial, nociceptive CLBP and exam demonstrating functional lumbar instability, which differs from other structural etiologies. Diagnostic images may be used to grade multifidus atrophy and assess other structural pathologies. While various treatments exist for CLBP, restorative neurostimulation distinguishes itself from traditional neurostimulation in a way that treats a different etiology, targets a different anatomical site, and has a distinctive mechanism of action.

CONCLUSIONS

Multifidus dysfunction has been proposed to result from loss of neuromuscular control, which may manifest clinically as muscle inhibition resulting in altered movement patterns. Over time, this cycle may result in potential atrophy, degeneration and CLBP. Restorative neurostimulation, a novel implantable neurostimulator system, stimulates the efferent lumbar medial branch nerve to elicit repetitive multifidus contractions. This intervention aims to interrupt the cycle of dysfunction and normalize multifidus activity incrementally, potentially restoring neuromuscular control. Restorative neurostimulation has been shown to reduce pain and disability in CLBP, improve quality of life and reduce health care expenditures.

Prevalence of dance-related injuries and associated risk factors among children and young Chinese dance practitioners

While Chinese dance is a popular dance genre among Chinese teenagers and adults, little is known regarding the prevalence of dance-related injuries or factors associated with such injuries among Chinese dance practitioners. The current cross-sectional study aimed to determine the prevalence of dance-related injuries and their associated risk factors among young Chinese dance practitioners in Hong Kong. Online surveys were distributed to dancers through local dance associations, while paper-based surveys were distributed to young Chinese dance performers during the 54th School Dance Festival in Hong Kong. Self-reported hours of dancing, injuries in the last 12 months, injury sites, and related factors were collected. The injury rate, 12-month prevalence of dance-related injuries were determined. Risk factors for common dance injuries were analyzed using separate multivariate regression models. A total of 175 children (aged 10-14 years) and 118 young (aged 15-24 years) Chinese dance practitioners provided their dance injury information. Young dancers had a significantly higher injury rate (6.5 injuries vs 4.6 injuries/1000 dance hours) and 12-month prevalence (52.5% vs 19.4%) than their child counterparts. The most commonly injured sites were the knee (children:7.4%; young:15.3%), lower back (children: 4.6%; young: 9.5%), and ankles (children: 5.1%; young: 16.9%). Age was a significant independent risk factor for dance-related injuries to the upper back, lower back, and pelvis/buttock (odds ratios ranging from 1.2 to 1.3/additional years). Additionally, height was a significant independent risk factor for lower limb injury (odds ratios ranging from 1.0-1.1/additional centimeter). Collectively, young Chinese dance practitioners are more vulnerable to dance-related injuries than are child dancers. Older age increases the risk of trunk injuries, whereas taller dancers are more likely to sustain lower-limb injuries. Future research should determine the mechanisms underlying dance-related injuries among these dancers.

The Effects of Combined Motor Control and Isolated Extensor Strengthening versus General Exercise on Paraspinal Muscle Morphology, Composition, and Function in Patients with Chronic Low Back Pain: A Randomized Controlled Trial

Low back pain (LBP), a globally widespread and persistent musculoskeletal disorder, benefits from exercise therapy. However, it remains unclear which type leads to greater changes in paraspinal muscle health. This study aimed to (1) compare the effects of a combined motor control and isolated lumbar extension exercise (MC+ILEX) versus a general exercise (GE) intervention on paraspinal muscle morphology, composition, and function, and (2) examine whether alterations in paraspinal muscle health were correlated with improvements in pain, function, and quality of life. Fifty participants with chronic LBP were randomly assigned to each group and underwent a 12-week supervised intervention program. Magnetic resonance imaging and ultrasound assessments were acquired at baseline, 6 and 12 weeks to examine the impact of each intervention on erector spinae (ES) and multifidus (MF) muscle size (cross-sectional area, CSA), composition, and function at L4-L5 and L5-S1. Self-reported questionnaires were also acquired to assess participant-oriented outcomes. Our findings indicated that the MC+ILEX group demonstrated greater improvements in MF and ES CSA, along with MF thickness at both levels (all p < 0.01). Both groups significantly improved in pain, function, and quality of life. This study provided preliminary results suggesting that an MC+ILEX intervention may improve paraspinal morphology while decreasing pain and disability.

Challenges, Concerns, and Experiences of Community-Dwelling Older Women with Chronic Low Back Pain—A Qualitative Study in Hong Kong, China

Background and Objectives: Although chronic low back pain (CLBP) is known to negatively affect multiple aspects of the lives of older people, prior qualitative studies mainly focused on the lived experiences of older people with CLBP in Western countries. Given cultural and contextual differences and poor understanding of CLBP in older women with CLBP, it is important to better understand the concerns and lived experiences of Chinese older women with CLBP. The current study aimed to investigate the experiences, challenges, concerns, and coping strategies of older women with CLBP in Hong Kong. Research Design and Methods: A total of 15 community-dwelling older women with CLBP aged ≥60 years were recruited from a physiotherapy clinic or a community center for semi-structured interviews. The interviews were audio recorded and transcribed ‘verbatim’. The transcription was imported to NVivo 12 software. Thematic analysis was conducted using Braun and Clarke’s method. Results: Five themes were identified: (1) physical impacts of CLBP on daily life; (2) psychological influences of CLBP; (3) management of CLBP; (4) family support; and (5) social activities and support. Discussion and implications: Negative physical and psychosocial impacts of CLBP were common among older women, and they adopted diverse pain management strategies, although some of their treatment options were influenced by the Chinese culture. Misbeliefs and responses of family and friends also affected their management strategies. Elderly community centers are a significant source of social support for older women with CLBP, making it an ideal platform for establishing self-help groups to facilitate their self-management of CLBP.

Experiences of community-dwelling older adults with chronic low back pain in Hong Kong and Switzerland - A qualitative study

Introduction

The prevalence of chronic low back pain (LBP) increases with age and older adults are more vulnerable to develop chronic LBP. A recent Swiss study has shown that 78% of community-dwelling older adults aged ≥65 years experienced chronic LBP. Similarly, a study in Hong Kong found that approximately 30% of people aged above 60 years experienced chronic LBP. The aim of this collaborative research project was to illuminate older adults' experiences of living with chronic LBP and its implication on older adults' daily life in Western and Eastern cultures.

Methods

Twenty-five older people experiencing chronic LBP living in Switzerland or Hong Kong were recruited through health professionals or community centres. Using semi-structured interviews, participants shared their experiences regarding chronic LBP and its implications on their daily life. The interviews were recorded and transcribed "ad verbatim" in the original language. An inductive thematic analysis was used, using a qualitative data analysis software program (NVivo) and a shared code book in English. The Swiss and Hong Kong research teams engaged in collaborative analysis until a consensus was established, taking into consideration of cultural specificities. Ethical approval was obtained from the local ethic committees in both regions.

Results

Themes were related to negative perceptions/experiences: (1) interferences of daily function; (2) pessimistic attitudes toward their conditions/prognosis; and (3) self-perceived burden related to families. Conversely, four themes revealed attributes to social roles: (1) maintaining their roles in families; (2) experiencing supports from family and friends; (3) being content despite LBP; and (4) enjoying social activities. Cultural differences between Switzerland and Hong Kong were related to social circles and offers from the healthcare system, influencing individual experiences and perceptions.

Discussion

Although chronic LBP may negatively impact older adults, individual approaches as well as social and health system supports influence older adults' attitude toward their pain and self-management strategies. Developing effective and culturally sensitive interventions for an elderly population with chronic LBP can be challenging but essential for the development of innovative healthcare services tailored to the population's needs. The methodological approach used for this research project establishes the framework for developing and evaluating complex interventions.

Motor Control: A Conceptual Framework for Rehabilitation

There is a lack of conceptual and theoretical clarity among clinicians and researchers regarding the control of motor actions based on the use of the term "motor control." It is important to differentiate control processes from observations of motor output to improve communication and to make progress in understanding motor disorders and their remediation. This article clarifies terminology related to theoretical concepts underlying the control of motor actions, emphasizing how the term "motor control" is applied in neurorehabilitation. Two major opposing theoretical frameworks are described (i.e., direct and indirect), and their strengths and pitfalls are discussed. Then, based on the proposition that sensorimotor rehabilitation should be predicated on one comprehensive theory instead of an eclectic mix of theories and models, several solutions are offered about how to address controversies in motor learning, optimality, and adaptability of movement.

Effectiveness of lumbar stabilization exercise with real-time ultrasound imaging biofeedback on lumbar multifidus muscle cross-sectional area in individuals with non-specific chronic low back pain: a study protocol for a randomized controlled trial

BACKGROUND

Structural impairment of the lumbar multifidus muscle, such as reduced cross-sectional area, is evident among individuals with chronic low back pain. Real-time ultrasound imaging (RUSI) biofeedback has been reported to improve preferential activation of as well as retention in the ability to activate the lumbar multifidus muscle during lumbar stabilization exercises (LSE). However, evidence of the effectiveness of this treatment approach in individuals with non-specific chronic low back pain (NCLBP) is still limited. The purpose of this study is, therefore, to determine the effectiveness of LSE with RUSI biofeedback on lumbar multifidus muscle cross-sectional area in individuals with NCLBP.

METHODS/DESIGN

This study is a prospective, single-center, assessor-blind, three-arm, parallel randomized controlled trial to be conducted at National Orthopedic Hospital, Kano State, Nigeria. Ninety individuals with NCLBP will be randomized in a 1:1:1: ratio to receive LSE, LSE with RUSI biofeedback, or minimal intervention. All participants will receive treatment twice weekly for 8 weeks. The primary outcome will be the lumbar multifidus muscle cross-sectional area. The secondary outcomes will include pain (Numerical Pain Rating Scale), functional disability (Roland-Morris Disability Questionnaire), and quality of life (12-Item Short-Form Health Survey). All outcomes will be assessed at baseline, 8 weeks post-intervention,  and 3 months follow-up.

DISCUSSION

To our knowledge, this study will be the first powered randomized controlled trial to compare the effectiveness of LSE training with and without RUSI biofeedback in individuals with NCLBP. The outcome of the study may provide evidence for the effectiveness of LSE with RUSI biofeedback on enhancing the recovery of the lumbar multifidus muscle in individuals with NCLBP.

TRIAL REGISTRATION

Pan African Clinical Trials Registry ( PACTR201801002980602) . Registered on January 16, 2018.

Are Morphometric and Biomechanical Characteristics of Lumbar Multifidus Related to Pain Intensity or Disability in People With Chronic Low Back Pain After Considering Psychological Factors or Insomnia?

INTRODUCTION

Lumbar multifidus muscle (LMM) dysfunction is thought to be related to pain and/or disability in people with chronic low back pain (CLBP). Although psychosocial factors play a major role in pain/disability, they are seldom considered as confounders in analyzing the association between LMM and CLBP.

OBJECTIVES

This study aimed to determine: (1) differences in psychological factors, insomnia, and LMM characteristics between people with and without CLBP; (2) associations between psychological factors, insomnia, or LMM characteristics and low back pain (LBP) intensity or LBP-related disability in people with CLBP; and (3) whether LMM characteristics are related to LBP symptoms in people with CLBP after considering confounders.

METHODS

Seventy-eight volunteers with CLBP and 73 without CLBP provided sociodemographic information, filled the 11-point numeric pain rating scale and Roland-Morris disability questionnaire (RMDQ). They completed the Hospital Anxiety and Depression Scale (HADS), Pain Catastrophizing Scale (PCS), Fear Avoidance Belief Questionnaire (FAB), and Insomnia Severity Index Scale (ISI). Resting and contracted thickness of LMM at L4-S1 levels were measured from brightness-mode ultrasound images. Percent thickness changes of LMM at L4-S1 levels during contraction were calculated. Resting LMM stiffness at L4-S1 was measured by shear wave elastography. Associations among LMM, psychosocial or insomnia parameters and clinical outcomes were analyzed by univariate and multivariate analyses.

RESULTS

People with CLBP demonstrated significantly higher LBP-intensity, RMDQ, HADS, FAB, PCS, and ISI scores than asymptomatic controls (p < 0.05). The former also had significantly smaller percent thickness changes of LMM at L4/L5 during contraction. LBP-intensity was positively related to scores of PCS-total, PCS-helplessness, FAB-total, FAB-work, and ISI in people with CLBP (p < 0.05). RMDQ scores were positively associated with the scores of HADS-total, HADS-depression, PCS-total, FAB-total, FAB-physical activity, PCS-helplessness, and ISI in people with CLBP (p < 0.05). FAB-work and ISI scores together explained 24% of LBP-intensity. FAB-total scores alone explained 34% of variance of LBP-related disability in people with CLBP.

CONCLUSION

More fear-avoidance belief or insomnia is related to greater LBP-intensity and/or LBP-related disability in people with CLBP. Although people with CLBP were thought to have aberrant LMM morphometry/function, no LMM characteristics were related to LBP-intensity or LBP-related disability after considering other confounders.