Do Changes in Transversus Abdominis and Lumbar Multifidus During Conservative Treatment Explain Changes in Clinical Outcomes Related to Nonspecific Low Back Pain? A Systematic Review

Spinal degeneration and lumbar multifidus muscle quality may independently affect clinical outcomes in patients conservatively managed for low back or leg pain

Few non-surgical, longitudinal studies have evaluated the relations between spinal degeneration, lumbar multifidus muscle (LMM) quality, and clinical outcomes. None have assessed the potential mediating role of the LMM between degenerative pathology and 12-month clinical outcomes. This prospective cohort study used baseline and 12-month follow-up data from 569 patients conservatively managed for low back or back-related leg pain to estimate the effects of aggregate degenerative lumbar MRI findings and LMM quality on 12-month low back and leg pain intensity (0-10) and disability (0-23) outcomes, and explored the mediating role of LMM quality between degenerative findings and 12-month clinical outcomes. Adjusted mixed effects generalized linear models separately estimated the effect of aggregate spinal pathology and LMM quality. Mediation models estimated the direct and indirect effects of pathology on leg pain, and pathology and LMM quality on leg pain, respectively. Multivariable analysis identified a leg pain rating change of 0.99 [0.14; 1.84] (unstandardized beta coefficients [95% CI]) in the presence of ≥ 4 pathologies, and a disability rating change of - 0.65 [- 0.14; - 1.16] for each 10% increase in muscle quality, but no effect on back pain intensity. Muscle quality had a non-significant mediating role (13.4%) between pathology and leg pain intensity. The number of different pathologies present demonstrated a small effect on 12-month leg pain intensity outcomes, while higher LMM quality had a direct effect on 12-month disability ratings but no mediating effect between pathology and leg pain. The relations between degenerative pathology, LMM quality, and pain-related outcomes appear complex and may include independent pathways.

Three-dimensional freehand ultrasonography to measure muscle volume of the lumbar multifidus: Reliability of processing technique and validity through comparison to magnetic resonance imaging

There is a growing interest in muscle characteristics of the lumbar multifidus related to low back pain, but findings between studies are inconsistent. One of the issues explaining these conflicting findings might be the use of two-dimensional measures of cross-sectional area and thickness of the lumbar multifidus in most studies, which might be a suboptimal representation of the entire muscle volume. A three-dimensional volumetric assessment, combined with standardized imaging and processing measurement protocols, is highly recommended to quantify spinal muscle morphology. Three-dimensional freehand ultrasonography is a technique with large potential for daily clinical practice. It is achieved by combining conventional two-dimensional ultrasound with a motion-tracking system, recording the position and orientation of the ultrasound transducer during acquisition, resulting in a three-dimensional reconstruction. This study investigates intra- and interprocessor reliability for the quantification of muscle volume of the lumbar multifidus based on three-dimensional freehand ultrasound and its validity, in 31 patients with low back pain and 20 healthy subjects. Two processors manually segmented the lumbar multifidus on three-dimensional freehand ultrasound images using Stradwin software following a well-defined method. We assessed the concurrent validity of the measurement of multifidus muscle volume using three-dimensional freehand ultrasound compared with magnetic resonance imaging in 10 patients with low back pain. Processing reliability and agreement were determined using intraclass correlation coefficients, Bland-Altman plots, and calculation of the standard error of measurement and minimal detectable change, while validity was defined based on correlation analysis. The processing of three-dimensional freehand ultrasound images to measure lumbar multifidus volume was reliable. Good to excellent intraclass correlation coefficients were found for intraprocessor reliability. For interprocessor reliability, the intraclass correlation coefficients were moderate to good, emphasizing the importance of processing guidelines and training. A single processor analysis is preferred in clinical studies or when small differences in muscle volume are expected. The correlation between magnetic resonance imaging and three-dimensional freehand ultrasound measurements of lumbar multifidus volume was moderate to good but with a systematically smaller multifidus volume measured on three-dimensional freehand ultrasound. These results provide opportunities for both researchers and clinicians to reliably assess muscle structure using three-dimensional freehand ultrasound in patients with low back pain and to monitor changes related to pathology or interventions. To allow implementation in both research and clinical settings, guidelines on three-dimensional freehand ultrasound processing and training were provided.

Differential Effects of Classical vs. Sports Massage on Erector Spinae and Upper Trapezius Muscle Stiffness: A Shear-Wave Elastography Study in Young Women

Classical and sports massages are commonly used interventions, but their comparative effects on muscle stiffness remain unclear. Classical massage is more general and uses light to moderate pressure, and its main purpose is relaxation. Sports massage, on the other hand, is more specialized and targets the unique needs of massaged individuals using moderate to firm pressure. This study aimed to evaluate the impacts of classical and sports massages on the stiffness of the erector spinae (ES) and upper trapezius (UT) muscles. Fifteen recreationally active young women, aged 22.9 ± 1.2 years, underwent a randomized cross-over study (with three conditions). Participants received either a five-minute classical or sports massage or a passive rest as a control on distinct days. Muscle stiffness was assessed using shear-wave elastography. The ES shear modulus displayed a significant time effect (p < 0.001; η2 = 0.515) without noticeable differences between the conditions, and the time × massage-type interactions approached statistical significance (F = 2.014; p = 0.073). There was also a large and statistically significant effect of the time on the UT (F = 11.127; p < 0.001; η2 = 0.443). We could not prove that classical and sports massages reduced muscle stiffness. The absence of significant differences might be attributed to the specific intervention parameters (massage duration of 5 min) and the small, only young women sample size. Given some tendencies towards significant effects, larger sample sizes are needed to further investigate this research question.

The Role of Back Muscle Dysfunctions in Chronic Low Back Pain: State-of-the-Art and Clinical Implications

Changes in back muscle function and structure are highly prevalent in patients with chronic low back pain (CLBP). Since large heterogeneity in clinical presentation and back muscle dysfunctions exists within this population, the potential role of back muscle dysfunctions in the persistence of low back pain differs between individuals. Consequently, interventions should be tailored to the individual patient and be based on a thorough clinical examination taking into account the multidimensional nature of CLBP. Considering the complexity of this process, we will provide a state-of-the-art update on back muscle dysfunctions in patients with CLBP and their implications for treatment. To this end, we will first give an overview of (1) dysfunctions in back muscle structure and function, (2) the potential of exercise therapy to address these dysfunctions, and (3) the relationship between changes in back muscle dysfunctions and clinical parameters. In a second part, we will describe a framework for an individualised approach for back muscle training in patients with CLBP.

The short-term effects of instrument-based mobilization compared with manual mobilization for low back pain: A randomized clinical trial

BACKGROUND

Despite being used as a manipulation technique, no studies have examined the effectiveness of physiotherapy instrument mobilization (PIM) as a mobilization technique on pain and functional status in patients with low back pain (LBP).

OBJECTIVE

To investigate the effectiveness of PIM in patients with LBP and to compare it with the effectiveness of manual mobilization.

METHODS

This is a double blind, randomized clinical trial. Thirty-two participants with LBP were randomly assigned to one of two groups. The PIM group received lumbar mobilization using an activator instrument, stabilization exercises, and education; and the manual group received lumbar mobilization using a pisiform grip, stabilization exercises, and education. Both groups had a total of 4 treatment sessions over 2-3 weeks. The following outcomes were measured before the intervention, and after the first and fourth sessions: Numeric Pain Rating Scale (NPRS), Oswestry Disability Index (ODI) scale, Pressure pain threshold (PPT), lumbar spine range of motion (ROM), and lumbar multifidus muscle activation.

RESULTS

There were no differences between the PIM group and the manual group in any outcome measures. However, over the period of study, there were improvements in both groups in NPRS (PIM: 3.23, Manual: 3.64 points), ODI (PIM: 17.34%, Manual: 14.23%), PPT (PIM: ⩽ 1.25, Manual: ⩽ 0.85 kg.cm2), lumbar spine ROM (PIM: ⩽ 9.49∘, Manual: ⩽ 0.88∘), and/or lumbar multifidus muscle activation (percentage thickness change: PIM: ⩽ 4.71, Manual: ⩽ 4.74 cm; activation ratio: PIM: ⩽ 1.17, Manual: ⩽ 1.15 cm).

CONCLUSIONS

Both methods of lumbar spine mobilization demonstrated comparable improvements in pain and disability in patients with LBP, with neither method exhibiting superiority over the other.

Effect of Motor Control Training on Trunk Muscle Morphometry, Pain, and Disability in People With Chronic Low Back Pain: A Systematic Review and Meta-Analysis

OBJECTIVE

The aim of this systematic review and meta-analysis was to study the effects of motor control training (MCT) on trunk muscle morphometry measured by ultrasound imaging and pain and disability in individuals with chronic low back pain.

METHODS

PubMed, Web of Science, Scopus, and Cochrane Library databases were searched from study inception until January 2021. Randomized control trials evaluating both muscle morphometry and pain or disability in individuals with chronic low back pain were included. Study selection, data extraction, and quality assessment were performed by 2 reviewers independently. Modified Downs and Black tool and the Grading of Recommendations Assessment, Development and Evaluation approach were used to assess the risk of bias and quality of evidence, respectively. A meta-analysis was performed using a random effects model with mean difference or standardized mean difference (SMD).

RESULTS

Of 3459 studies initially identified, 15 studies were included, and 13 studies were selected for meta-analysis. The results revealed no differences in the resting thickness of the transversus abdominis, internal and external oblique, and lumbar multifidus muscles in studies that compared MCT with other interventions. The transversus abdominis muscles contraction ratio was greater (SMD = 0.93; 95% confidence interval [CI], -0.0 to 1.85) and lower pain (weighted mean difference: -1.07 cm; 95% CI, -1.91 to -0.22 cm; P = .01) and disability (SMD = -0.86; 95% CI, -1.42 to -0. 29; P < .01) scores were found in the groups who underwent MCT compared with other interventions.

CONCLUSION

This systematic review and meta-analysis found that motor control exercise training increased the transverse abdominis contraction ratio (muscle activation) and improved the level of pain and disability compared to other interventions in people with chronic low back pain. However, motor control exercise training was not superior to other interventions in increasing the resting thickness of deep abdominal and lumbar multifidus muscles in intervention times less than 12 weeks.

Reliability and agreement of lumbar multifidus volume and fat fraction quantification using magnetic resonance imaging

INTRODUCTION

Magnetic resonance imaging (MRI) is the standard to quantify size and structure of lumbar muscles. Three-dimensional volumetric measures are expected to be more closely related to muscle function than two-dimensional measures such as cross-sectional area. Reliability and agreement of a standardized method should be established to enable the use of MRI to assess lumbar muscle characteristics.

OBJECTIVES

This study investigates the intra- and inter-processor reliability for the quantification of (1) muscle volume and (2) fat fraction based on chemical shift MRI images using axial 3D-volume measurements of the lumbar multifidus in patients with low back pain.

METHODS

Two processors manually segmented the lumbar multifidus on the MRI scans of 18 patients with low back pain using Mevislab software following a well-defined method. Fat fraction of the segmented volume was calculated. Reliability and agreement were determined using intra-class correlation coefficients (ICC), Bland-Altman plots and calculation of the standard error of measurement (SEM) and minimal detectable change (MDC).

RESULTS

Excellent ICCs were found for both intra-processor and inter-processor analysis of lumbar multifidus volume measurement, with slightly better results for the intra-processor reliability. The SEMs for volume were lower than 4.1 cm³. Excellent reliability and agreement were also found for fat fraction measures, with ICCs of 0.985-0.998 and SEMs below 0.946%.

CONCLUSION

The proposed method to quantify muscle volume and fat fraction of the lumbar multifidus on MRI was highly reliable, and can be used in further research on lumbar multifidus structure.

A Preliminary Study on the Equivalence between Standing Back-Extension and Superman Training in Lumbar Multifidus Exercise

Objective. To explore the equivalence of an easier and more convenient lumbar multifidus (LM) muscle exercise pattern among standing back-extension, static standing, and superman training. Methods. A total of 26 healthy young volunteers were enrolled, including 14 males and 12 females, aged from 22 to 44 years with an average of $31.77\pm 7.06$ years. Ultrasonography was used to measure the thickness of the left LM of the transverse process of the L5 vertebra during static standing, static prone decubitus, standing back-extension, and prone superman training. In this study, measurement data were expressed as $\text{Mean}\pm \text{SD}$ and compared using the $t$ -test. Results. The left LM thickness of the L5 vertebra was $2.92\pm 0.46$  cm during static standing and $2.78\pm 0.39$  cm during static prone decubitus, showing no statistical difference between the two groups ( $P>0.05$ ). The left LM thickness of the L5 vertebra was $3.16\pm 0.51$  cm during standing back-extension and $3.33\pm 0.41$  cm during the prone superman training, indicating no statistical difference between the two groups ( $P>0.05$ ). Conclusions. There is no significant statistical difference in the LM thickness between static standing and static prone decubitus and between standing back-extension and prone superman training, indicating the equivalence of the two methods in LM exercise, providing a simpler and easier way for clinical exercise of lumbodorsal muscles.

Wrist, but Not Back, Isometric Contraction Induced Widespread Hypoalgesia in Healthy Participants

Objective: Exercise may reduce pain sensitivity. This phenomenon called exercise-induced hypoalgesia is observed in different types of exercises and involves the activation of endogenous pain modulation systems. Although the effect of limb exercise on pain sensitivity has often been tested, few studies explored the impact of back exercises that are often used to treat low back pain. The main objective is to measure the effect of back-muscle exercise on pain sensitivity and compare it to the effect of a limb-muscle exercise.

Methods: Twenty-three participants who were pain-free performed a 4-min wrist flexion isometric contraction followed by a 4-min low back extension, separated by a 20-min break. Pressure pain thresholds were tested at two low back (S1 spinous process, lumbar erector spinae muscle) and two wrist (capitate bone, wrist flexor muscles) sites before and after each exercise. For each exercise, sites were considered as remote or local in relation to the muscles contracted during the exercise. An independent sample of 11 participants was recruited to confirm the influence of low back extension on pain sensitivity.

Results: Wrist exercise induced a larger increase in pain sensitivity than back exercise at the remote site. Only wrist exercise induced a hypoalgesia effect at both the local and the remote sites. Back exercise induced a similar effect in the independent sample.

Conclusions: This study showed that back and wrist exercises induced a distinct effect on pain sensitivity in participants who were pain-free. The wrist exercise induced a systemic reduction in pain sensitivity (locally and remotely), whereas the back exercise did not. This differential effect may be present because wrist exercise induced most fatigue compared with the back exercise.

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.

Are Changes in Sleep Quality/Quantity or Baseline Sleep Parameters Related to Changes in Clinical Outcomes in Patients With Nonspecific Chronic Low Back Pain?: A Systematic Review

OBJECTIVES

Sleep disturbance is prevalent among patients with chronic low back pain (CLBP). This systematic review aimed to summarize the evidence regarding the: (1) temporal relations between changes in sleep quality/quantity and the corresponding changes in pain and/or disability; and (2) role of baseline sleep quality/quantity in predicting future pain and/or disability in patients with CLBP.

METHODS

Four databases were searched from their inception to February 2021. Two reviewers independently screened the abstract and full text, extracted data, assessed the methodological quality of the included studies, and evaluated the quality of evidence of the findings using the Grading of Recommendations Assessment Development and Evaluation (GRADE).

RESULTS

Of 1995 identified references, 6 articles involving 1641 participants with CLBP were included. Moderate-quality evidence substantiated that improvements in self-reported sleep quality and total sleep time were significantly correlated with the corresponding LBP reduction. Low-quality evidence showed that self-reported improvements in sleep quality were related to the corresponding improvements in CLBP-related disability. There was conflicting evidence regarding the relation between baseline sleep quality/quantity and future pain/disability in patients with CLBP.

DISCUSSION

This is the first systematic review to accentuate that improved self-reported sleep quality/quantity may be associated with improved pain/disability, although it remains unclear whether baseline sleep quality/quantity is a prognostic factor for CLBP. These findings highlight the importance of understanding the mechanisms underlying the relation between sleep and CLBP, which may inform the necessity of assessing or treating sleep disturbance in people with CLBP.

Choosing what works for whom: towards a better use of mechanistic knowledge in clinical practice

BACKGROUND

Clinicians commonly try to use mechanism-based knowledge to make sense of the complexity and uncertainty of chronic pain treatments to create a rationale for their clinical decision-making. Although this seems intuitive, there are some problems with this approach.

DISCUSSION

The widespread use of mechanism-based knowledge in clinical practice can be a source of confusion for clinicians, especially when complex interventions with different proposed mechanisms of action are equally effective. Although the available mechanistic evidence is still of very poor quality, in choosing from various treatment options for people with chronic pain, an approach that correctly incorporates mechanistic reasoning might aid clinical thinking and practice.

CONCLUSION

By explaining that not all evidence of mechanism is the same and by making a proposal to start using mechanism-based knowledge in clinical practice properly, we hope to help clinicians to incorporate mechanistic reasoning to prioritize and start choosing what may best work for whom.

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

Aberrant morphological changes in lumbar multifidus muscle (LMM) are prevalent among patients with low back pain (LBP). Motor control exercise (MCE) aims to improve the activation and coordination of deep trunk muscles (eg, LMM), which may restore normal LMM morphology and reduce LBP. However, its effects on LMM morphology have not been summarized. This review aimed to summarize evidence regarding the (1) effectiveness of MCE in altering LMM morphometry and decreasing LBP; and (2) relations between post-MCE changes in LMM morphometry and LBP/LBP-related disability. Cumulative Index to Nursing and Allied Health Literature, MEDLINE, Cochrane Central Register of Controlled Trials, the Physiotherapy Evidence Database, EMBASE and SPORTDiscus were searched from inception to 30 September 2020 to identify relevant randomized controlled trials. Two reviewers independently screened articles, extracted data, and evaluated risk of bias and quality of evidence. Four hundred and fifty-one participants across 9 trials were included in the review. Very low-quality evidence supported that 36 sessions of MCE were better than general physiotherapy in causing minimal detectable increases in LMM cross-sectional areas of patients with chronic LBP. Very low- to low-quality evidence suggested that MCE was similar to other interventions in increasing resting LMM thickness in patients with chronic LBP. Low-quality evidence substantiated that MCE was significantly better than McKenzie exercise or analgesics in increasing contracted LMM thickness in patients with chronic LBP. Low-quality evidence corroborated that MCE was not significantly better than other exercises in treating people with acute/chronic LBP. Low-quality evidence suggested no relation between post-MCE changes in LMM morphometry and LBP/LBP-related disability. Collectively, while MCE may increase LMM dimensions in patients with chronic LBP, such changes may be unrelated to clinical outcomes. This raises the question regarding the role of LMM in LBP development/progression.

The Effect of Virtual Reality Training on Anticipatory Postural Adjustments in Patients with Chronic Nonspecific Low Back Pain: A Preliminary Study

Objectives

This study is aimed at exploring the effects of virtual reality (VR) training on postural control, measured by anticipatory and compensatory postural adjustments (APAs and CPAs, respectively), in patients with chronic nonspecific low back pain (CNLBP) and the potential neuromuscular mechanism of VR training.

Methods

Thirty-four patients were recruited and randomly assigned to the VR group (n = 11), the motor control exercise group (MCE, n = 12) and the control group (CG, n = 11). The VR group received VR training using Kinect Xbox 360 systems and magnetic therapy. Besides magnetic therapy, the participants in the MCE group performed real-time ultrasound-guided abdominal drawing-in maneuver (ADIM) and four-point kneeling exercise. The CG only received magnetic therapy. Surface muscle electromyography (sEMG) was used to record the muscle activities of transverse abdominis (TrA), multifidus (MF), lateral gastrocnemius (LG), and tibialis anterior (TA) during ball-hitting tasks. The muscle activation time and integrals of the electromyography activities (IEMGs) during the APA and CPA stages were calculated and used in the data analysis. The visual analogue scale (VAS) and Oswestry dysfunction index (ODI) scores were also recorded.

Results

A significant interaction effect of time × group was observed on the activation time of TrA (p = 0.018) and MF (p = 0.037). The post-intervention activation time of the TrA was earlier in the VR group (p = 0.029). In contrast, the post-intervention activation time of the MF was significantly delayed in the VR group (p = 0.001). The IEMGs of TrA (p = 0.002) and TA (p = 0.007) during CPA1 significantly decreased only in the VR group after the intervention. The VAS scores of three group participants showed significant decreases after intervention (p < 0.001).

Conclusions

Patients with CNLBP showed reciprocal muscle activation patterns of the TrA and MF muscles after VR training. VR training may be a potential intervention for enhancing the APAs of the patients with CNLBP.

Lumbar Multifidus Muscle Morphology Changes in Patient with Different Degrees of Lumbar Disc Herniation: An Ultrasonographic Study

Background and Objective: Previous studies demonstrated that the prevalence of lumbar disc herniation (LDH) is relatively high. This investigation aimed to evaluate the size of lumbar multifidus (LM) muscle in patients with different degrees of LDH compared to healthy group, during rest and contraction, using ultrasonography. Materials and Methods: In this non-experimental, analytic, and case control study, ultrasound imaging was used to assess cross-sectional area (CSA) and thickness of the LM muscle in 15 healthy subjects and 60 patients with different stages of LDH (bulging group = 15, protrusion group = 15, extrusion group = 15, sequestration group = 15). Measurements were taken bilaterally at the L4-L5 level, during rest and contraction and results were compared between groups. Results: There was a significant difference between healthy subjects and the extrusion and sequestration groups during rest and contraction for LM muscle CSA and thickness (p = 0.001), as LM muscle CSA and thickness were significantly smaller in extrusion and sequestration patient groups compared to healthy subjects. LM atrophy was greater in patients with extrusion and sequestration groups than in patients with bulging and protrusion, both at rest and during contraction. Significant correlations were also observed between functional disability and intensity of pain with LM CSA and thickness measurements. Conclusions: Patients with extrusion and sequestration LDH had smaller LM muscle at rest and during contraction compared to healthy subjects. Larger LDH lesions were associated with decreased LM muscle size. Patient with more pain, disability, and extrusion and sequestration LDH had greater LM size changes. LM muscle size was not correlated with symptom duration. Further investigation with greater sample size is warranted.

Changes in physiotherapy students' beliefs and attitudes about low back pain through pre-registration training

BACKGROUND

Implementation of best-practice care for patients with low back pain (LBP) is an important issue. Physiotherapists' who hold unhelpful beliefs are less likely to adhere to guidelines and may negatively influence their patients' beliefs. Pre-registration education is critical in moving towards a biopsychosocial model of care. This study aimed to investigate the changes in 2nd year physiotherapy students' beliefs about LBP after a module on spinal pain management and determine whether these changes were maintained at the end of academic training.

METHODS

During three consecutive calendar years, this longitudinal cohort study assessed physiotherapy students' beliefs with the Back Pain Attitudes Questionnaires (Back-PAQ) in their 1st year, before and after their 2nd year spinal management learning module, and at the end of academic training (3rd year). Unpaired t-tests were conducted to explore changes in Back-PAQ score.

RESULTS

The mean response rate after the spinal management module was 90% (128/143 students). The mean (± SD) Back-PAQ score was 87.73 (± 14.21) before and 60.79 (± 11.44) after the module, representing a mean difference of - 26.95 (95%CI - 30.09 to - 23.80, p < 0.001). Beliefs were further improved at the end of 3rd year (- 7.16, 95%CI - 10.50 to - 3.81, p < 0.001).

CONCLUSIONS

A spinal management learning module considerably improved physiotherapy students' beliefs about back pain. Specifically, unhelpful beliefs about the back being vulnerable and in need of protection were substantially decreased after the module. Improvements were maintained at the end of academic training one-year later. Future research should investigate whether modifying students' beliefs leads to improved clinical practice in their first years of practice.

Effect of Core Stabilizing Training on Young Individuals Presenting Different Stages of Degenerative Disc Disease-Preliminary Report

The aim of this study was to assess the efficacy of stabilizing training for the deep core muscles of the lumbar spine in subjects with degenerative disc disease. This study was conducted on 38 participants. The participants were divided into two groups: the extrusion group (EXT, n = 17) and the protrusion group (PRO, n = 21). All the subjects underwent a four-week-long core stability exercise-based treatment (five sessions/week). Clinical outcome measures were assessed pre-intervention (pre), post-intervention (post) and four weeks after the intervention (follow-up). The primary outcome measures were the spinal range of motion (ROM; Spinal Mouse^® device) and the Oswestry Disability Index (ODI). In the PRO group, the ROM decreased from 88.52° pre-intervention to 83.33° post-intervention and to 82.82° at follow-up (p = 0.01), while the ODI decreased from 16.14 points pre-intervention to 6.57 points post-intervention, with 9.42 points at follow-up (p < 0.01). In the EXT group, the ROM decreased from 81.00° pre-intervention to 77.05° post-intervention, then increased to 77.94° at follow-up (p = 0.03), while the ODI decreased from 22.58 points pre-intervention to 15.41 points post-intervention and to 14.70 points at follow-up (p < 0.001). Although the stabilizing exercise sessions improved the clinical outcomes in each group, we cannot make conclusions as to whether the type of intervertebral disc damage significantly affects the results of stabilizing exercise-based treatment.

Is the pain pressure threshold linked to the transversus abdominis in women with chronic neck pain?: a preliminary report

PURPOSE

The present study aimed to investigate the relationship between the ultrasonography parameters of transversus abdominis and neck pain manifestations in women with chronic neck pain.

MATERIALS AND METHODS

Thirty women (mean age: 38.44 ± 9.56 years, BMI: 25.57 ± 3.32 kg/m²) with chronic neck pain were included in the study. The pain severity, disability scores, and bilateral pain pressure threshold of upper trapezius were assessed. The thickness of transversus abdominis in-rest and abdominal draw-in conditions were evaluated by two-dimensional ultrasonography. Pearson's correlation coefficients and linear regression statistics were determined.

RESULTS

We found a moderate correlation between the thickness of transversus abdominis in abdominal draw-in and the pain pressure threshold of right (r = 0.636, p < 0.001), and left upper trapezius (r = 0.403, p = 0.03). Moreover, there was a moderate correlation between the pain pressure threshold of the right upper trapezius and the thickness of transversus abdominis in-rest (r = 0.498, p = 0.006). No significant correlation was found between pain intensity, disability scores, and ultrasonography parameters of transversus abdominis. There was also a significant total effect of transversus abdominis' thickness on abdominal draw-in manoeuvre on predicting pain pressure threshold of right upper trapezius (B = 0.636, SE = 0.765, p < 0.001) and pain pressure threshold of left upper trapezius (B = 0.403, SE = 0.840, p = 0.03).

CONCLUSIONS

Our results revealed that upper trapezius muscle tenderness may associated with decreased muscle thickness of transversus abdominis. Addressing new exercise methodologies including transversus abdominis training in the management of chronic neck pain may be helpful to improve neck pain symptoms.

Reproducibility and Concurrent Validity of Manual Palpation with Rehabilitative Ultrasound Imaging for Assessing Deep Abdominal Muscle Activity: Analysis with Preferential Ratios

The abdominal drawing-in maneuver (ADIM) is a clinical tool used for identifying preferential activity of deep abdominal muscles. However, concurrent validity and reproducibility of palpation during the ADIM has not been formally investigated. The aims of this study were (1) to assess intra- and interrater reliability of manual palpation during the ADIM, and (2) to determine the concurrent validity of manual palpation during the ADIM by calculating preferential activation ratio cut-off as assessed with ultrasound imaging (RUSI). Thirty-two subjects (n = 16 patients with nonspecific low back pain and 16 comparable healthy individuals) performed the ADIM in a supine hook-lying position. Two experienced assessors evaluated the presence or absence of preferential contraction of the deep abdominal muscles by palpation during the ADIM on 2 different days. Intrarater (test-retest) and interrater reliability of palpation were calculated using Cohen's kappa coefficients. Muscle thickness of the transverse abdominis (TrA), internal oblique (IO), and external oblique (EO) muscles at rest and during the ADIM were also measured. TrA-Contraction Ratio (TrA-CR), TrA-Preferential Activation Ratio (TrA-PAR), and Modified-TrA-PR (M-TrA-PAR) were calculated. The concurrent validity of manual palpation was determined using the correlation between manual palpation and imaging and by calculating ROC curve (operating characteristics curve), Youden index, and sensitivity and specificity. Intra- and interrater reliability of manual palpation during the ADIM was excellent (k: 0.82-1.00) and good to excellent (k: 0.71-1.00), respectively. Interrater reliability for muscle thickness ranged from good to excellent (ICC3,1 0.79-0.91). Manual palpation and TrA ratio showed low to moderate correlations (r: 0.36-0.60). When evaluating the diagnostic accuracy of manual palpation, the best predictive model (ROC value: 0.89; p < 0.001) for correct a preferential contraction of TrA was obtained when the M-TrA-PAR was ≥0.08 (sensitivity: 0.95-1.00; specificity: 0.62). Good to excellent intra- and interrater reliability of manual palpation was found during the ADIM in both patients and healthy groups. Manual palpation showed concurrent validity for identifying the preferential activity of the TrA muscle supporting its use in clinical practice.

Effects of electromyographic biofeedback interventions for shoulder pain and function: Systematic review and meta-analysis

OBJECTIVE

To systematically review the effectiveness of electromyographic biofeedback interventions to improve pain and function of patients with shoulder pain.

DESIGN

Systematic review of controlled clinical trials.

LITERATURE SEARCH

Databases (Medline, EMBASE, CINAHL, PEDro, CENTRAL, Web of Science, and SCOPUS) were searched in December 2020.

STUDY SELECTION CRITERIA

Randomized clinical trials that investigated the effects of electromyographic biofeedback for individuals with shoulder pain. Patient-reported pain and functional outcomes were collected and synthesized.

DATA SYNTHESIS

The level of evidence was synthesized using GRADE and Standardized Mean Differences and 95% confidence interval were calculated using a random-effects inverse variance model for meta-analysis.

RESULTS

Five studies were included with a total sample of 272 individuals with shoulder pain. Very-low quality of evidence indicated that electromyographic biofeedback was not superior to control for reducing shoulder pain (standardized mean differences = -0.21, 95% confidence interval: -0.67 to 0.24, P = 0.36). Very-low quality of evidence indicated that electromyographic biofeedback interventions were not superior to control for improving shoulder function (standardized mean differences = -0.11, 95% confidence interval: -0.41 to 0.19, P = 0.48).

CONCLUSION

Electromyographic biofeedback may be not effective for improving shoulder pain and function. However, the limited number of included studies and very low quality of evidence does not support a definitive recommendation about the effectiveness of electromyographic biofeedback to treat individuals with shoulder pain.

Prevalence/Incidence of Low Back Pain and Associated Risk Factors Among Nursing and Medical Students: A Systematic Review and Meta-Analysis

OBJECTIVE

To summarize evidence regarding the prevalence and incidence of low back pain and associated risk factors in nursing and medical students. TYPE: Systematic review and meta-analysis.

LITERATURE SURVEY

The protocol was registered with PROSPERO (CRD42015029729). Its reporting followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Seven databases were searched until August 2020 to identify relevant studies.

METHODOLOGY

Two independent reviewers screened, extracted, and evaluated the risk of bias of the selected studies. Meta-analyses were used to estimate 12-month prevalence/incidence rates of low back pain and associated risk factors in these students. Levels of evidence for risk factors were determined by the updated Guidelines for Systematic Reviews in the Cochrane Collaboration Back Review Group.

SYNTHESIS

Sixteen studies involving 7072 students were included. The pooled 12-month prevalence rates of low back pain for nursing and medical students were 44% (95% confidence interval [95% CI]: 27%-61%) and 53% (95% CI: 44%-62%), respectively. The 12-month incidence of low back pain in nursing students ranged from 29% to 67%. No incidence rate was reported in medical students. Strong/moderate-quality evidence supported that final year of study (pooled odds ratio [OR] from five studies, 1.96, 95% CI: 1.13-3.40), anxiety (OR ranging from 3.12 to 4.61), or high mental pressure or psychological distress (OR ranging from 1.37 to 4.52) was associated with a higher 12-month low back pain prevalence in both student groups. Moderate-quality evidence suggested that prior history of low back pain (pooled OR from two studies: 3.46, 95% CI: 1.88-6.36) was associated with a higher 12-month low back pain incidence in nursing students. Similarly, moderate-quality evidence suggested that female medical students (pooled OR from two studies: 1.77, 95% CI: 1.09-2.86) demonstrated a higher 12-month low back pain prevalence than male counterparts.

CONCLUSIONS

Although it is impossible to alter nonmodifiable risk factors for low back pain, universities may develop and implement proper strategies to mitigate modifiable risk factors in these students.

The Politics of Chronic LBP: Can We Rely on a Proxy-Vote? Linking Multifidus Intra-Myo-Cellular Lipid (IMCL) Fatty Infiltration With Arthrogenic Muscle Inhibition (AMI)-induced Chronic Nonspecific Low Back Pain

STUDY DESIGN

Retrospective review of the literature.

OBJECTIVE

To update recent trends in the use of magnetic resonance spectroscopy (MRS) analysis for CLBP.

SUMMARY OF BACKGROUND DATA

The lumbar multifidus (MF) muscle has drawn sustained interest for some time, particularly related to its structure, role in spinal stability, and its association and clinical significance with CLBP. Additionally, the presence of MF-arthrogenic muscle inhibition (AMI) and its relation to induced CLBP, through depleted lumbar stabilization, has gained increased recognition. In contrast, the differential diagnostic use of MRS analysis has suggested specific links between the presence of MF myo-cellular lipid (MCL) infiltration and CLBP patients.

METHODS

Review of the literature related to CLBP with the keywords MCL, MRS analysis, and MF-AMI.

RESULTS

No articles discussed CLBP using the three key concepts in a single context. The use of MRS analysis has the capacity to distinguish between Extra-MCL (EMCL) and intra-MCL (IMCL) infiltration within the lumbar MF. It is suggested that EMCLs are more likely to be associated with age-related change, while the IMCLs appear more likely to be associated with the presence of CLBP. The increased recognition of MF-AMI as a primary cause of CLBP, and the potential that AMI parallels the presence of IMCLs, facilitates possible use of MRS as a means to quantify the basis of lumbar MF-AMI CLBP, and that proportional IMCL changes in the MF could serve as a 'proxy' to indicate the effectiveness of interventions directed at MF activation.

CONCLUSIONS

It may be possible for IMCLs to serve as a 'proxy' prognostic marker of lumbar MF-AMI in CLBP patients. Further, if this assertion were correct, then reductions in IMCLs could potentially quantify recovery and the efficacy of rehabilitation management strategies directed at lumbar MF activation.Level of Evidence: 5.

Mapping of Back Muscle Stiffness along Spine during Standing and Lying in Young Adults: A Pilot Study on Spinal Stiffness Quantification with Ultrasound Imaging

Muscle stiffness in the spinal region is essential for maintaining spinal function, and might be related to multiple spinal musculoskeletal disorders. However, information on the distribution of muscle stiffness along the spine in different postures in large subject samples has been lacking, which merits further investigation. This study introduced a new protocol of measuring bilateral back muscle stiffness along the thoracic and lumbar spine (at T3, T7, T11, L1 & L4 levels) with both ultrasound shear-wave elastography (SWE) and tissue ultrasound palpation system (TUPS) in the lying and standing postures of 64 healthy adults. Good inter-/intra-reliability existed in the SWE and TUPS back muscle stiffness measurements (ICC ≥ 0.731, p < 0.05). Back muscle stiffness at the L4 level was found to be the largest in the thoracic and lumbar regions (p < 0.05). The back muscle stiffness of males was significantly larger than that of females in both lying and standing postures (p < 0.03). SWE stiffness was found to be significantly larger in standing posture than lying among subjects (p < 0.001). It is reliable to apply SWE and TUPS to measure back muscle stiffness. The reported data on healthy young adults in this study may also serve as normative reference data for future studies on patients with scoliosis, low back pain, etc.

Contributions of Muscle Elasticity and Lateral Slide of the Transversus Abdominis to Lumbar Stability

CONTEXT

Lumbar instability can cause lumbar spondylolisthesis and chronic low-back pain in sports situation. Abdominal hollowing is commonly used in clinical practice to preferentially target the transversus abdominis (TrA) to stabilize the lumbar vertebrae; however, the contribution of muscle elasticity and lateral slide of the TrA to lumbar stability has not yet been clarified.

OBJECTIVE

To clarify the contribution of elasticity and lateral slide of the TrA to lumbar stability and to identify an effective exercise to stabilize the lumbar vertebrae.

DESIGN

Experimental study.

SETTING

Laboratory.

PATIENTS

A total of 29 healthy males participated in this study.

INTERVENTIONS

The participants performed hollowing during measurement of muscle elasticity of TrA and both knees extension from crook lying position for pelvic stability measurement.

MAIN OUTCOME MEASURES

Lumbar stability, muscle elasticity change ratio, and lateral slide amount of TrA.

RESULTS

There was a significant correlation between elasticity of the TrA and lumbar stability; however, no relationship was observed between lateral slide and lumbar stability or elasticity of the TrA.

CONCLUSION

Elasticity of the TrA and lumbar stability was significantly correlated; therefore, improving the tonicity of the TrA may stabilize the lumbar vertebrae in healthy individuals. Moreover, hollowing with maximum effort may be effective as training aimed to stabilize the lumbar vertebrae for physical dysfunction due to lumbar instability.

Automatic Characterizations of Lumbar Multifidus Muscle and Intramuscular Fat with Fuzzy C-means based Quantization from Ultrasound Images

BACKGROUND

Low Back Pain (LBP) is a common disorder involving the muscles and bones and about half of the people experience LBP at some point of their lives. Since the social economic cost and the recurrence rate over the lifetime is very high, the treatment/rehabilitation of chronic LBP is important to physiotherapists, both for clinical and research purposes. Trunk muscles such as the lumbar multifidi is important in spinal functions and intramuscular fat is also important in understanding pain control and rehabilitations. However, the analysis of such muscles and related fat require many human interventions and thus suffers from the operator subjectivity especially when the ultrasonography is used due to its cost-effectiveness and no radioactive risk.

AIMS

In this paper, we propose a fully automatic computer vision based software to compute the thickness of the lumbar multifidi muscles and to analyze intramuscular fat distribution in that area.

METHODS

The proposed system applies various image processing algorithms to enhance the intensity contrast of the image and measure the thickness of the target muscle. Intermuscular fat analysis is done by Fuzzy C-Means (FCM) clustering based quantization.

RESULTS

In experiment using 50 DICOM format ultrasound images from 50 subjects, the proposed system shows very promising result in computing the thickness of lumbar multifidi.

CONCLUSION

The proposed system have minimal discrepancy(less than 0.2 cm) from human expert for 72% (36 out of 50 cases) of the given data. Also, FCM based intramuscular fat analysis looks better than conventional histogram analysis.

The Effects of Stabilization Exercise on the Thickness of Lateral Abdominal Muscles During Standing Tasks in Women With Chronic Low Back Pain: A Randomized Triple-Blinded Clinical Trial Study

CONTEXT

Chronic low back pain (CLBP) often presents with a dysfunction in deep abdominal muscles activity during standing tasks. Although some studies indicated that deep abdominal muscle activity improved during some functional tasks following stabilization exercise (SE), there is no study to evaluate the effect of SE on lateral abdominal muscles thickness during standing postural tasks.

OBJECTIVE

The purpose of this study was (1) to evaluate the lateral abdominal muscles thickness in the participants with CLBP while standing on a balance board and (2) to compare the effects of SE and a general exercise (GE) program on the lateral muscles thickness changes.

METHODS

This was a between-groups, triple-blinded randomized controlled trial design. In total, 40 females with CLBP were randomly assigned into 2 groups:  GE (control group) and supervised progressive SE (experimental group). Diagnostic ultrasound imaging was used before and after the intervention to measure lateral abdominal muscles thickness during standing on 2 different levels of platform in the Biodex Balance System. Visual analog scale and Roland-Morris Disability Questionnaire were used to evaluate changes in pain intensity and disability.

RESULTS

The results indicated significant increases in transverse abdominis muscle thickness during all standing tasks (P = .02) and significant decreases in pain intensity and disability following SE intervention (P < .001). However, the lateral abdominal muscle thicknesses were not changed after GE intervention while standing postural tasks (P > .05). The GE group revealed only significant decreases in pain intensity after intervention (P = .03).

CONCLUSION

Supervised progressive SE improved the activity of deep abdominal muscles in standing postural tasks in the patients with CLBP.

Factors Associated With the Ultrasound Characteristics of the Lumbar Multifidus: A Systematic Review

OBJECTIVE

The first aim of this review was to investigate the association between age, sex, height, weight, physical activity level, posture, lumbar level and body side, and structural characteristics (cross-sectional area [CSA], thickness, linear dimensions, and echo intensity) of the lumbar multifidus (LM) measured by ultrasound. Second, differences between healthy individuals and patients with chronic low back pain (CLBP) were investigated. TYPE: Systematic review.

LITERATURE SURVEY

PubMed, Embase and Web of Science were searched until September 2018.

METHODOLOGY

Studies were included if (a) full text was available in English, Dutch, or French; (b) participants were older than 18 years of age and were asymptomatic or had nonspecific CLBP; and (c) the relation between structural characteristics of the LM, measured by ultrasound, and at least one of the above-mentioned factors was described, and/or a comparison between a CLBP and control group was made. Data were extracted independently by two reviewers. Quality of studies was assessed using an adapted version of the Downs and Black checklist.

SYNTHESIS

Twenty-seven studies were included. Thickness and CSA of the LM do not correlate with age. Males have a larger LM size than females. Thickness and CSA of left and right LM are highly correlated in healthy subjects. More significant side-to-side differences are present in subjects with CLBP than in those without. Muscle size increases from proximal to caudal lumbar levels. The presence of CLBP is associated with muscle size and function.

CONCLUSIONS

The association between the factors age, sex, height, weight, physical activity level, posture, lumbar level, body side, and presence of CLBP, and the ultrasound characteristics of the LM is discussed. These factors should be taken into account in future research on structural muscle characteristics, or when correlating with functional behavior or investigating the effect of a targeted intervention.

LEVEL OF EVIDENCE

I.

Supersonic Shear Imaging for Quantification of Lateral Abdominal Muscle Shear Modulus in Pediatric Population with Scoliosis: A Reliability and Agreement Study

The aim of this study was to assess the intra- and inter-rater reliability/agreement of the lateral abdominal muscle (LAM) stiffness and thickness measurements at rest and during contraction and to determine the relationship between the superficial fat thickness and the LAM stiffness measurements. LAM stiffness and thickness were measured using supersonic shear wave elastography (SSI) in pediatric participants. The reliability of LAM stiffness and thickness measurements ranged from moderate to excellent. There was an inverse correlation between fat thickness and between-rater difference in the resting external oblique stiffness (r > -0.37) and the contracted external and internal oblique stiffness (r > -0.40). SSI is a reliable method for assessing LAM stiffness and thickness in pediatric populations. To remove potential systematic errors: (i) the first round of measurements should be performed to familiarize patients with procedures; (ii) the examiner should pay more attention while performing LAM measurements on the opposite side of the body.

Can Biomechanics Research Lead to More Effective Treatment of Low Back Pain? A Point-Counterpoint Debate

SYNOPSIS

Although biomechanics plays a role in the development and perhaps the persistent or recurrent nature of low back pain (LBP), whether biomechanics alone can provide the basis for intervention is debated. Biomechanics, which refers to the mechanics of the body, including its neuromuscular control, has been studied extensively in LBP. But, can gains be made in understanding LBP by research focused on this component of biology in the multifactorial biopsychosocial problem of LBP? This commentary considers whether biomechanics research has the potential to advance treatment of LBP, and how likely it is that this research will lead to better treatment strategies. A point-counterpoint format is taken to present both sides of the argument. First, the challenges faced by an approach that considers biomechanics in isolation are presented. Next, we describe 3 models that place substantial emphasis on biomechanical factors. Finally, reactions to each point are presented as a foundation for further research and clinical practice to progress understanding of the place for biomechanics in guiding treatment of LBP. J Orthop Sports Phys Ther 2019;49(6):425-436. Epub 15 May 2019. doi:10.2519/jospt.2019.8825.

Evidence of stabilizing exercises for low back- and pelvic girdle pain - a critical review

BACKGROUND

Pregnancy-related low back pain (LBP) and pelvic girdle pain (PGP) have been associated with an alteration in the strategy for lumbopelvic stabilization. Different core stabilization approaches exist, the evidence is however controversial.

METHODS

This paper discusses how to improve the evidence of exercises for women suffering from LBP and PGP during and after pregnancy. Exercises should be understood in a context, where the bio-psycho-social perspective directs the prescription of exercises, targeting both psychological and physical factors. The type of exercise probably should be individually tailored to the needs and capability of the individual and it is not only about the most appropriate exercise, it is about dosage and delivery of the exercises, and it is about performance. To promote adherence the use of patient preferences, with self-defined movement goals, may be a motivational basis for behavior change. Communication skills may facilitate positive beliefs and provide a motivational foundation for empowerment, self-efficacy and for self-management. To learn by discovery where the patient learns through their own experiences, might motivate the patients to active engagement and to behavioral change. Adherence probably will increase when the patients understand the aim and the rationale behind the exercises they are prescribed. However, with high adherence to exercises that maintains an inappropriate motor pattern, LBP and PGP possibly could proceed into chronicity.

CONCLUSION

Exercises need to be meaningful to the patient, relevant for daily activities, individualized according to patient preferences, guided and supervised to secure performance and quality.

The influence of musculoskeletal pain disorders on muscle synergies-A systematic review

Background

Musculoskeletal (MSK) pain disorders represent a group of highly prevalent and often disabling conditions. Investigating the structure of motor variability in response to pain may reveal novel motor impairment mechanisms that may lead to enhanced management of motor dysfunction associated with MSK pain disorders. This review aims to systematically synthesize the evidence on the influence of MSK pain disorders on muscle synergies.

Methods

Nine electronic databases were searched using Medical Subject Headings and keywords describing pain, electromyography and synergies. Relevant characteristics of included studies were extracted and assessed for generalizability and risk of bias. Due to the significant heterogeneity, a qualitative synthesis of the results was performed.

Results

The search resulted in a total of 1312 hits, of which seven articles were deemed eligible. There was unclear consistency that pain reduced the number of muscle synergies. There were low consistencies of evidence that the synergy vector (W weights) and activation coefficient (C weights) differed in painful compared to asymptomatic conditions. There was a high consistency that muscle synergies were dissimilar between painful and asymptomatic conditions.

Conclusions

MSK pain alters the structure of variability in muscle control, although its specific nature remains unclear. Greater consistency in muscle synergy analysis may be achieved with appropriate selection of muscles assessed and ensuring consistent achievement of motor task outcomes. Synergy analysis is a promising method to reveal novel understandings of altered motor control, which may facilitate the assessment and treatment of MSK pain disorders.

Relationships between paraspinal muscle morphology and neurocompressive conditions of the lumbar spine: a systematic review with meta-analysis

Background

Individual study results have demonstrated unclear relationships between neurocompressive disorders and paraspinal muscle morphology. This systematic review aimed to synthesize current evidence regarding the relationship lumbar neurocompressive disorders may have with lumbar paraspinal muscle morphology.

Methods

Searches were conducted in seven databases from inception through October 2017. Observational studies with control or comparison groups comparing herniations, facet degeneration, or canal stenosis to changes in imaging or biopsy-identified lumbar paraspinal muscle morphology were included. Data extraction and risk of bias assessment were performed by review author pairs independent of one another. Morphological differences between individuals with and without neurocompressive disorders were compared qualitatively, and where possible, standardised mean differences were obtained.

Results

Twenty-eight studies were included. Lumbar multifidus fiber diameter was smaller on the side of and below herniation for type I [SMD: −0.40 (95% CI = −0.70, −0.09) and type II fibers [SMD: −0.38 (95% CI = −0.69, −0.06)] compared to the unaffected side. The distribution of type I fibers was greater on the herniation side [SMD: 0.43 (95% CI = 0.03, 0.82)]. Qualitatively, two studies assessing small angular fiber frequency and fiber type groupings demonstrated increases in these parameters below the herniation level. For diagnostic imaging meta-analyses, there were no consistent differences across the various assessment types for any paraspinal muscle groups when patients with herniation served as their own control. However, qualitative synthesis of between-group comparisons reported greater multifidus and erector spinae muscle atrophy or fat infiltration among patients with disc herniation and radiculopathy in four of six studies, and increased fatty infiltration in paraspinal muscles with higher grades of facet joint degeneration in four of five studies. Conflicting outcomes and variations in study methodology precluded a clear conclusion for canal stenosis.

Conclusions

Based on mixed levels of risk of bias data, in patients with chronic radiculopathy, disc herniation and severe facet degeneration were associated with altered paraspinal muscle morphology at or below the pathology level. As the variability of study quality and heterogeneous approaches utilized to assess muscle morphology challenged comparison across studies, we provide recommendations to promote uniform measurement techniques for future studies.

Trial registration

PROSPERO 2015: CRD42015012985

Electronic supplementary material

The online version of this article (10.1186/s12891-018-2266-5) contains supplementary material, which is available to authorized users.

Feasibility, accuracy and safety of a percutaneous fine-needle biopsy technique to obtain qualitative muscle samples of the lumbar multifidus and erector spinae muscle in persons with low back pain

The lumbar muscular system, in particular the lumbar multifidus muscle (LM) and the erector spinae muscle (ES), plays an important role in stabilizing and mobilizing the lumbar spine. Based on the topography, the lumbar paraspinal muscles can be classified into local and global muscles. LM is part of the local system, whereas ES is part of the global system. Therefore, it is interesting to investigate the muscle fibre type composition in both muscles. There is accumulating evidence that nonspecific chronic low back pain is associated with lumbar muscle dysfunction. To further elucidate this lumbar paraspinal muscle dysfunction, it is important to understand the structural characteristics of individual muscle fibres of LM and ES. Muscle fibre type composition can be investigated in muscle tissue samples. So far, muscle samples are taken by using invasive procedures that are not well tolerated. The aim of this article was to evaluate the feasibility, accuracy and safety of a percutaneous fine-needle biopsy technique to obtain muscle samples from LM and ES in persons with nonspecific chronic low back pain and to evaluate the feasibility of performing immunofluorescence analysis of myosin heavy chain isoform expression to investigate muscle fibre type composition. Preliminary investigations in cadavers were performed to determine the optimal vertebral level and puncture site to obtain muscle samples of LM and ES through a single skin puncture. In 15 persons with nonspecific chronic low back pain, muscle samples of LM and ES were taken under local anaesthesia with the percutaneous fine-needle biopsy technique, preceded by determination of the puncture site with ultrasonography. Muscle fibre type composition was investigated using immunofluorescence analysis of myosin heavy chain expression. The subjects reported little or no pain and were willing to repeat the procedure. The obtained muscle tissue contained transverse-sectioned muscle fibres in which muscle fibre contractile characteristics of the paraspinal muscles could be evaluated with immunofluorescence analysis of the myosin heavy chains. We can conclude that percutaneous microbiopsy appears to be feasible and accurate, and safe to use to obtain muscle tissue from the paraspinal muscles. The use of ultrasonography to determine the puncture site is necessary to ensure biopsy of the correct muscles and to ensure the safety of the procedure.

The Role of a Multi-Step Core Stability Exercise Program in the Treatment of Nurses with Chronic Low Back Pain: A Single-Blinded Randomized Controlled Trial

Study Design

Single-blinded randomized controlled trial.

Purpose

To evaluate the effects of a multi-step core stability exercise program in nurses with chronic low back pain (CLBP).

Overview of Literature

CLBP is a common disorder among nurses. Considering that patient-handling activities predispose nurses to CLBP, core stability exercises suggested for managing CLBP in the general population may also be helpful in nurses. However, sufficient evidence is not available on whether a multi-step core stability exercise program affects pain, disability, quality of life, and the diameter of lateral abdominal muscles in nurses with CLBP.

Methods

In this single-blinded randomized controlled trial, 36 female nurses with CLBP were recruited. The sample was divided into two groups of 18 patients (intervention and control). Nurses in the intervention group performed core stability exercises for 8 weeks, based on a progressive pattern over time. Roland–Morris Disability Questionnaire (RDQ), quality of life (36-item Short Form Health Survey [SF-36]), ultrasound assessment of the diameter of lateral abdominal muscles, and Visual Analog Scale (VAS) score for pain were evaluated in the participants before and after the trial. Sixteen nurses (eight from each group) dropped out of the study, and analysis of covariance was used to compare outcomes for the remaining nurses in the intervention (10 nurses) and control (10 nurses) groups.

Results

The results after the trial showed significant improvements in RDQ, SF-36, and VAS score in the intervention group compared with that in the control group (p <0.005). Furthermore, the ultrasound data showed a significant increase in the left and right muscle diameter of all three abdominal muscles during the abdominal drawing-in maneuver in the intervention group compared with that in the control group (p <0.05).

Conclusions

This study showed that a multi-step core stability exercise program is a helpful treatment option for improving quality of life and reducing disability and pain in female nurses with CLBP.

Effectiveness of an Osteopathic Abdominal Manual Intervention in Pain Thresholds, Lumbopelvic Mobility, and Posture in Women with Chronic Functional Constipation

OBJECTIVES

To assess the effect of an osteopathic abdominal manual intervention (AMI) on pressure pain thresholds (PPTs), mobility, hip flexibility, and posture in women with chronic functional constipation.

DESIGN

Randomized, double-blind placebo-controlled trial.

SETTING/LOCATION

Subjects were recruited for the study by referral from different gastroenterology outpatient clinics in the city of Madrid (Spain).

SUBJECTS

Sixty-two patients suffering from chronic functional constipation according to the guidelines of the Congress of Rome III.

INTERVENTIONS

The experimental group (n = 31) received an osteopathic AMI, and the control group (n = 31) received a sham procedure.

OUTCOME MEASURES

PPTs at different levels, including vertebral levels C7, T3, T10, T11, and T12, trunk flexion range of motion (ROM), hip flexibility, and posture, were measured before and immediately after the intervention. A comparison between the difference between the pre- and postintervention values using the Student's t test for independent samples or nonparametric U-Mann-Whitney test depending on the distribution normality of the analyzed variables was perfomed.

RESULTS

In the intergroup comparison, statistically significant differences were found in PPT at T11 (p = 0.011) and T12 (p = 0.001) and also in the trunk flexion ROM (p < 0.05). Moreover, women showed no adverse effects with acceptable pain tolerance to the intervention.

CONCLUSION

The application of an osteopathic AMI is well tolerated and improves pain sensitivity in areas related to intestinal innervation, as well as lumbar flexion.

Motor skill training in musculoskeletal pain: a case report in chronic low back pain

Purpose: Low back pain is a chronic condition that limits function. The chief reason individuals with low back pain seek care is difficulty performing functional activities. A novel approach to improving performance of painful and limited functional activities is motor skill training, defined as challenging practice of activities to learn or relearn a skill. The purpose of this report is to describe the design and application of a motor skill training intervention in a 26-year-old man with a 10-year history of low back pain. Methods: A motor skill training intervention was implemented to modify the altered alignment and movement patterns he used during the performance of his painful and limited activities. Results: The patient was seen for six visits in 12 weeks. The patient reported decreased pain and medication use, as well as improved function immediately, 3-, and 9-months post-intervention. Conclusion: Individuals with low back pain report limitation in ability to perform everyday functions and demonstrate altered patterns of movement and alignment during these activities. This case report describes an innovative motor skill training intervention that directly addresses the performance of functional activities and the application of motor learning principles. Implications for rehabilitation Low back pain is a chronic condition that limits function. The chief reason individuals with chronic low back pain seek care is difficulty performing everyday functional activities. Motor skill training is a novel approach that directly addresses the performance of painful and limited functional activities through challenging practice to improve performance and decrease pain.

Comparative Study of Abdominal Muscle Thickness on Ultrasonography in Healthy Adolescents and Patients With Low Back Pain

OBJECTIVES

Low back pain (LBP) is a common musculoskeletal disorder among different age groups, including adolescents. The purpose of this study was to compare the abdominal muscle thickness between healthy adolescents and those with LBP.

METHODS

One hundred sixty healthy high school adolescents and 80 high school adolescents with LBP participated in the study. All participants were asked to complete a demographic questionnaire and also a visual analog scale and the Oswestry Disability Questionnaire to evaluate the pain intensity and functional disability. Then abdominal muscle thickness was examined with ultrasonography.

RESULTS

The healthy high adolescents included 80 boys and 80 girls, and the adolescents with LBP included 40 boys and 40 girls. The results showed a significant difference between healthy adolescents and those with LBP in terms of abdominal muscle thickness (P < .05). Patients with LBP had smaller abdominal muscles compared with healthy adolescents. No significant difference was found between the groups in terms of the subcutaneous fat dimension (P > .05).

CONCLUSIONS

The thickness of abdominal muscles was lower in adolescents with LBP. Future studies with a larger sample and a wider age range are recommended to support the results of this study.

Chronic low back pain and back muscle activity during functional tasks

There is evidence that patients with low back pain favor their trunk muscles when moving. However, it is unknown whether this maladaptive behavior is generalized across different functional tasks. This study analyzed the back muscle activity of patients with chronic low back pain compared to asymptomatic controls during five functional tasks. The secondary aim of this study was to test whether the electromyographic activity of patients' back muscles was correlated with either the TAMPA scale score or the Örebro Questionnaire. Forty patients with chronic, non-specific low back pain and 40 asymptomatic participants were assessed on the electromyographic activity of the lumbar longissimus, ilio-costal and multifidus while picking up and placing an object on the ground, sitting down and standing up, and climbing stairs. There was statistical evidence of two-way interactions involving group by task (F_4,308 = 7.921, p < 0.001, η² = 0.049) and task by muscle (F_18,1386 = 2.912, p < 0.001, η² = 0.004), but not group by muscle (F_7,539 = 1.104, p = 0.359, η² = 0.004). Patients with chronic low back pain showed an increase in back muscle activity regardless of the type of functional task, except the left side of multifidus muscle during the picking up of a ball on the ground task. There was no correlation between the measure of kinesiophobia or the Örebro questionnaire score and the level of electromyographic activity.

Psychometric Properties of the Deep Muscle Contraction Scale for Assessment of the Drawing-in Maneuver in Patients With Chronic Nonspecific Low Back Pain

Study Design A prospective cohort study. Background Motor control dysfunctions have been commonly reported in patients with chronic nonspecific low back pain (LBP). Physical therapists need clinical tools with adequate psychometric properties to assess such patients in clinical practice. The deep muscle contraction (DMC) scale is a clinical rating scale for assessing patients' ability to voluntarily contract deep abdominal muscles. Objectives To investigate the intrarater reliability, floor and ceiling effects, internal and external responsiveness, and correlation analysis (with ultrasound measures) of the DMC scale in patients with chronic nonspecific LBP undergoing a lumbar stabilization exercise program. Methods Sixty-two patients with chronic nonspecific LBP were included. At baseline, self-report questionnaires were administered to patients and a trained assessor evaluated abdominal muscle recruitment with the DMC scale and ultrasound imaging. Four ratios of the change in abdominal muscle thickness between the resting and contracted states were calculated through the ultrasound measures. After 1 week, the same ultrasound measures and DMC scale were collected again for the reliability analysis. The proportions of patients with the lowest and highest scores on the DMC scale were calculated to investigate floor and ceiling effects. All patients underwent a lumbar stabilization program, administered twice a week for 8 weeks. After the treatment period, all measures were collected again, with the addition of the global perceived effect scale, to assess the internal and external responsiveness of the measures. Correlation coefficients between ultrasound ratios and DMC scale total and subscale scores were also calculated. Results The intrarater reliability of the DMC scale and the 4 ratios of abdominal muscle thickness varied from moderate to excellent. The DMC scale showed no floor or ceiling effects. Results for internal responsiveness of the DMC scale showed large effect sizes (2.26; 84% confidence interval [CI]: 2.06, 2.45), whereas the external responsiveness was below the proposed threshold (area under the curve = 0.54; 95% CI: 0.39, 0.68). Fair and significant correlations between some ultrasound ratios and DMC subscales were found. Conclusion The DMC scale was demonstrated to be a reliable tool, with no ceiling and floor effects, and to detect change in the ability to contract the deep abdominal muscles after a lumbar stabilization exercise program, but with low accuracy for estimating patient-perceived clinical outcome. J Orthop Sports Phys Ther 2017;47(6):432-441. doi:10.2519/jospt.2017.7140.

Physiotherapists report improved understanding of and attitude toward the cognitive, psychological and social dimensions of chronic low back pain after Cognitive Functional Therapy training: a qualitative study

QUESTION

What are physiotherapists' perspectives on managing the cognitive, psychological and social dimensions of chronic low back pain after intensive biopsychosocial training?

DESIGN

Qualitative study design using semi-structured interviews to explore physiotherapists' perceptions of their identification and treatment of the biopsychosocial dimensions of chronic low back pain after intensive Cognitive Functional Therapy (CFT) training.

PARTICIPANTS

Thirteen qualified physiotherapists from four countries who had received specific CFT training. The training involved supervised implementation of CFT in clinical practice with patients. Interviews were audio-recorded and transcribed verbatim. An interpretive descriptive analysis was performed using a qualitative software package.

RESULTS

Four main themes emerged from the data: self-reported changes in understanding and attitudes; self-reported changes in professional practice; altered scope of practice; and increased confidence and satisfaction. Participants described increased understanding of the nature of pain, the role of patient beliefs, and a new appreciation of the therapeutic alliance. Changes in practice included use of new assessments, changes in communication, and adoption of a functional approach. Since undertaking CFT training, participants described a greater awareness of their role and scope of practice as clinicians in identifying and addressing these factors.

CONCLUSION

Physiotherapists expressed confidence in their capacity and skill set to manage the biopsychosocial dimensions of chronic low back pain after CFT training, and identified a clear role for including these skills within the physiotherapy profession. Despite this, further clinical trials are needed to justify the time and cost of training, so that intensive CFT training may be made more readily accessible to clinicians, which to date has not been the case. [Synnott A, O'Keeffe M, Bunzli S, Dankaerts W, O'Sullivan P, Robinson K, O'Sullivan K (2016) Physiotherapists report improved understanding of and attitude toward the cognitive, psychological and social dimensions of chronic low back pain after Cognitive Functional Therapy training: a qualitative study.Journal of Physiotherapy62: 215-221].

Establishing Immediate Reliability of Sonographic Measurements of the Transversus Abdominis in Asymptomatic Adults Performing Upright Loaded Functional Tasks in a Clinical Context Without Delayed Recorded Measurement

OBJECTIVES

This study examined the reliability of sonographic measurements of the transversus abdominis of adults without low back pain during upright loaded functional tasks in real time, without relying on delayed recorded images.

METHODS

A single-group repeated-measures reliability study was conducted on 12 healthy participants without low back pain. Six of these adults reported a prior history of abdominal drawing-in maneuver training without sonographic measurement. The participants performed 3 trials of neutral standing, a loaded forward reach, and a loaded box lift under rest and with abdominal drawing-in maneuver instructions; task order was randomized. Transversus abdominis thickness measurements were obtained by an experienced rater using B-mode sonography in real-time via electronic calipers twice on the same static image during all trials by a rater. The rater was masked to group assignment and on-screen measurement output and required to respond to trivia questions between repeated measurements.

RESULTS

The participants included 6 male and 6 female adults with a mean age ± SD of 26.3 ± 3.7 years. Intra-rater intraclass correlation coefficients (2,3) were high and precise for the rater's first and second measurements for all tasks and instruction conditions for mean transversus abdominis thickness and percent change in thickness measurements (eg, ranges were 0.968-0.997 for intraclass correlation coefficients, 0.01-0.21 mm for standard errors of the measurement, and 0.01-0.58 mm for minimal detectable changes). Calipers cleared by the rater or a research assistant produced similar findings of excellent reliability and precision.

CONCLUSIONS

High intra-rater reliability and precision of transversus abdominis thickness measurements were obtained by a physical therapist in real time from asymptomatic adults performing upright loaded functional tasks under rest and with abdominal drawing-in maneuver instructions.

A Randomized Controlled Trial Comparing the McKenzie Method to Motor Control Exercises in People With Chronic Low Back Pain and a Directional Preference

Study Design Randomized clinical trial. Background Motor control exercises are believed to improve coordination of the trunk muscles. It is unclear whether increases in trunk muscle thickness can be facilitated by approaches such as the McKenzie method. Furthermore, it is unclear which approach may have superior clinical outcomes. Objectives The primary aim was to compare the effects of the McKenzie method and motor control exercises on trunk muscle recruitment in people with chronic low back pain classified with a directional preference. The secondary aim was to conduct a between-group comparison of outcomes for pain, function, and global perceived effect. Methods Seventy people with chronic low back pain who demonstrated a directional preference using the McKenzie assessment were randomized to receive 12 treatments over 8 weeks with the McKenzie method or with motor control approaches. All outcomes were collected at baseline and at 8-week follow-up by blinded assessors. Results No significant between-group difference was found for trunk muscle thickness of the transversus abdominis (-5.8%; 95% confidence interval [CI]: -15.2%, 3.7%), obliquus internus (-0.7%; 95% CI: -6.6%, 5.2%), and obliquus externus (1.2%; 95% CI: -4.3%, 6.8%). Perceived recovery was slightly superior in the McKenzie group (-0.8; 95% CI: -1.5, -0.1) on a -5 to +5 scale. No significant between-group differences were found for pain or function (P = .99 and P = .26, respectively). Conclusion We found no significant effect of treatment group for trunk muscle thickness. Participants reported a slightly greater sense of perceived recovery with the McKenzie method than with the motor control approach. Level of Evidence Therapy, level 1b-. Registered September 7, 2011 at www.anzctr.org.au (ACTRN12611000971932). J Orthop Sports Phys Ther 2016;46(7):514-522. Epub 12 May 2016. doi:10.2519/jospt.2016.6379.

Effects of different verbal instructions on change of lumbar multifidus muscle thickness in asymptomatic adults and in patients with low back pain

BACKGROUND

Spinal stabilisation exercise has been shown to be effective in the rehabilitation of low back pain (LBP). Due to the isometric nature of spinal stabilisation exercise, manual therapists use various verbal instructions to elicit lumbar multifidus muscle contraction.

OBJECTIVES

The purpose of this study was to assess whether or not three verbal instructions would alter muscle thickness of the lumbar multifidus muscle differently in asymptomatic individuals and patients with LBP.

METHODS

Three verbal instructions were selected for this study: (1) swell the muscle underneath the transducer, (2) draw your belly button in towards your spinal column and (3) think about tilting your pelvis but without really doing it. Lumbar multifidus muscle thickness was determined using parasagittal ultrasound (US) imaging. Measurements of muscle thickness were collected at rest and during verbal instructions from 21 asymptomatic adults and 21 patients with LBP. Percent changes of muscle thickness during contraction and at rest were compared between groups and across verbal instructions.

RESULTS

ANOVA results showed no significant interaction for both L4-5 and L5-S1, but a significant main effect of verbal instruction (P = 0.049) at L4-5.Post hoc analysis showed a greater increase with verbal instruction #3 than verbal instruction #2 (P = 0.009). There was no significant main effect of group at either segment.

DISCUSSION

The results of the study suggest that both groups responded similarly to the three verbal instructions. Verbal instructions may increase lumbar multifidus muscle thickness by different amounts at L4-5, but by the same amount at L5-S1.

The abdominal drawing-in manoeuvre for detecting activity in the deep abdominal muscles: is this clinical tool reliable and valid?

OBJECTIVE

The abdominal drawing-in manoeuvre (ADIM) is a common clinical tool for manually assessing whether a preferential activation of the deep abdominal muscles in patients with low back pain (LBP) is 'correct' or not. The validity and reliability of manual assessment of the ADIM are, however, as yet unknown. This study evaluated the concurrent and discriminative validity and reliability of the manually assessed ADIM.

DESIGN

Single-blinded cross-sectional study.

SETTINGS

General population in Stockholm County, Sweden.

PARTICIPANTS

The study sample comprised 38 participants seeking care for LBP, and 15 healthy subjects.

MEASURES

The manual ADIM was assessed as correct or not following a standard procedure. Ultrasound imaging (USI) was used as the concurrent reference (gold standard) for the manually assessed ADIM by calculating a ratio of the change in muscle thickness between the resting and the contracted states: the correlation between manual test and USI was calculated. Discriminative validity was analysed by calculating sensitivity and specificity. A sample of 24 participants was analysed with κ coefficients for interobserver reliability between two raters.

RESULTS

The concurrent validity between the manual ADIM and the ADIM-USI ratios showed poor correlations (r=0.13-0.40). The discriminative validity of the manually assessed ADIM to predict LBP showed a sensitivity/specificity of 0.30/0.73, while the ADIM-USI ratio to predict LBP showed 0.19/0.87. The interobserver reliability for the manually assessed ADIM revealed substantial agreement: K=0.71, CI (95%) 0.41 to 1.00.

CONCLUSIONS

Although the interobserver reliability of the manually assessed ADIM was high, the concurrent and discriminative validity were both low for examining the preferential activity of the deep abdominal muscles. Neither the manually assessed ADIM nor the ultrasound testing discriminated between participants with LBP and healthy subjects regarding preferential activity of the transversus muscle as this ability/inability was also present in healthy subjects.

Validation of a Clinical Test of Thoracolumbar Dissociation in Chronic Low Back Pain

STUDY DESIGN

Clinical test validation.

OBJECTIVES

Preliminary study of concurrent and discriminant validity of a clinical test of thoracolumbar dissociation.

BACKGROUND

Control deficits of back muscles and trunk movement are common in chronic/recurrent low back pain (LBP). A reliable clinical test to rate an individual's ability to dissociate lumbopelvic movement from the thoracolumbar region has been described. This test rates the performance quality of 5 key aspects against criterion standards.

METHODS

Concurrent validity was examined by comparison of clinical test scores (overall score and each individual criterion) against spine kinematics. Discriminant validity was evaluated by comparison of scores between pain-free controls and participants with LBP. A receiver operating characteristic curve was calculated to determine the optimal cutoff or score to differentiate between good and poor performers.

RESULTS

Concurrent validity was supported by the significant correlation between the total score and motion of the T5 vertebra relative to the S1 vertebra (P<.05). Scores for some (4 correlations of 14 measures) but not all individual criteria were correlated with the kinematic features that each criterion was expected to reflect. Discriminant validity was supported by higher test scores for pain-free controls than for participants with LBP after 2 minutes of training (P = .045). Scores of less than 5.5 were more prevalent in the LBP group (pretraining LBP versus control, 72% versus 35%; P = .008; posttraining LBP versus control, 48% versus 16%; P = .018).

CONCLUSION

This preliminary study of concurrent and discriminant validity of the test provides a foundation to further investigate its utility to characterize thoracolumbar movement patterns in individuals with LBP.