Lumbar Multifidus Muscle Thickness Research Articles

Gender Differences in Balance, Lumbar Multifidus Muscle, Pain, and Kinesiophobia in Patients with Lumbar Spinal Stenosis

Aim: The aim of this study was to examine balance, lumbar multifidus muscle thickness and cross-sectional area (CSA), pain, disability and kinesiophobia levels, and to compare these parameters in terms of gender in patients with lumbar spinal stenosis (LSS).
 Material and Methods: This cross-sectional study included 59 patients, 33 (55.9%) female and 26 (44.1%) male, diagnosed with LSS by magnetic resonance imaging (MRI). Low back and leg pains, dynamic and static balances, disability and kinesiophobia levels of patients with LSS were evaluated. Lumbar multifidus muscle thickness and total CSA were obtained from MRI images. Obtained data were compared according to gender.
 Results: Females had significantly more low back pain than males (p=0.043), in patients with LSS. Additionally, females with LSS had worse dynamic and static balances (p=0.005, and p=0.001, respectively) and higher levels of disability (p=0.001), and kinesiophobia (p=0.001). Females with LSS had less lumbar multifidus muscle thickness and CSA than males on both the right and left sides. Also, right multifidus muscle thickness correlated with both dynamic (r=-0.289; p=0.027) and static (r=0.349; p=0.007) balances. Significant correlations were detected between low back and leg pain with dynamic and static balances, disability, and kinesiophobia in patients with LSS.
 Conclusion: Females with LSS have higher levels of pain, disability, and kinesiophobia than males. Also, LSS affects females' balance functions more and causes further degeneration of the multifidus muscle. Therefore, gender differences should be examined during the clinical follow-up process in LSS.

Potential role of thoracolumbar fascia in younger middle-aged patients with chronic low back pain

Aim This study aimed to quantitatively assess the thickness of the thoracolumbar fascia (TLF) and lumbar multifidus muscle through ultrasound imaging in younger-middle aged individuals, both those experiencing chronic low back pain (LBP) and those without LBP. Additionally, the study sought to explore the potential significance of these anatomical structures in relation to clinical and sonographic findings. Method A cross-sectional study was conducted involving a cohort of 50 participants, divided into two groups: chronic LBP group (Group LBP, n = 30) and a group without LBP (Group control, n = 20). Participants from both groups underwent assessments pertaining to pain characteristics (intensity and quality), functional impairment, and kinesiophobia. The thicknesses of the thoracolumbar fascia and lumbar multifidus muscle were measured using ultrasonography. Results Among participants with chronic LBP, the thoracolumbar fascia displayed a statistically significant increase in thickness on the left side, whereas the lumbar multifidus muscle exhibited reduced thickness on the left side. Notably, positive correlations were observed between the thickness of the thoracolumbar fascia and scores from the Numerical Rating Scale (NRS) for pain intensity (r = 0.472, p = 0.008) as well as the McGill Pain Questionnaire (MPQ) (r = 0.547, p = 0.002). Moreover, a positive correlation was established between the thickness of the lumbar multifidus muscle and the modified Schober test (r = 0.174, p = 0.040). However, the thickness of the lumbar multifidus muscle demonstrated a negative correlation with age (r = −0.304, p = 0.032). Multiple logistic regression analysis did not identify any significant predictors for the presence of LBP based on demographic or clinical variables. Conclusions Individuals afflicted with chronic LBP exhibited pronounced thickening of the thoracolumbar fascia and attenuation of the lumbar multifidus muscle in comparison to asymptomatic counterparts. Notably, increased thickness of the thoracolumbar fascia corresponded to heightened pain intensity, while reduction in lumbar multifidus muscle thickness was associated with decreased lumbar flexion ability. These findings underscore the importance of incorporating tailored regimens targeting both fascial and muscular components in the rehabilitation of individuals with LBP.

Effects of early aquatic exercise intervention on trunk strength and functional recovery of patients with lumbar fusion: a randomized controlled trial

This study investigated the effectiveness of an early aquatic exercise program on trunk muscle function and functional recovery of patients with lumbar fusion. Twenty-eight subjects were divided into two equal groups. Patients in the aquatic group performed two 60-min aquatic exercise sessions and three 60-min home exercise sessions per week for 6 weeks, whereas those in the control group performed five sessions of 60-min home exercises per week for 6 weeks. The primary outcomes were the Numerical Pain Rating Scale (NPRS) and Oswestry Disability Index (ODI), and the secondary outcomes were Timed Up and Go Test (TUGT), trunk flexor and extensor muscle strength, lumbopelvic stability, and lumbar multifidus muscle thickness measured pre- and post-intervention. Compared with participants in the control group, those in the experimental group showed significant improvement in NPRS, ODI, trunk extensor strength, lumbopelvic control, lumbar multifidus muscle thickness, and relative change in multifidus muscle thickness (significant time by group interactions, P < 0.05). Participants in both groups showed significant time effects (P < 0.001) for TUGT and trunk flexor strength outcome. Aquatic exercise combined with home exercise was superior to home exercise alone in reducing pain, disability and improving muscle strength, lumbopelvic stability, and lumbar multifidus muscle thickness.

Relationship between morphometric and mechanical properties of superficial lumbosacral soft tissue layers in healthy young adults.

Introduction: It is commonly considered that myotonometry is a non-invasive method capable of quantifying linear elastic and viscoelastic properties of the myofascial tissue through the application of a weak mechanical impulse to the surface of the skin. However, before the impulse can reach the myofascial tissue, it must cross more superficial tissues such as the skin and subcutaneous tissue (ST). All these superficial tissues have different distributions and organizations of structural components. Therefore, the study aimed to examine the potential relationships between the mechanical and morphometric properties of various superficial soft tissues surrounding the lumbar multifidus muscle (LM). Methods: Myotonometric measurements of dynamic stiffness, logarithmic decrement, and creep, and ultrasonographic measurements of thickness and echogenicity of cutaneous, subcutaneous, perimuscular tissue, and LM were obtained from 50 healthy individuals in the resting prone position and during contralateral arm lift. Results: The most important findings were that in both the relaxed and contracted LM state, the dynamic stiffness strongly negatively (r = -0.69; p < 0.001 in relaxation, r = -0.83; p < 0.001 in contraction) and creep strongly positively (r = 0.79; p < 0.001 in relaxation, r = 0.85; p < 0.001 in contraction) correlated with the thicknesses of the ST. Similar but weaker correlations were noticed between both these measures and the perimuscular tissue thickness. Elasticity was uncorrelated to the thicknesses of the tissues. With LM contraction (change from the relaxed to contracted state), the relative increase in dynamic stiffness was correlated with the relative decrease in dermis (r = -0.51; p < 0.001) and ST (r = -0.47; p = 0.001) thickness, and with the relative increase in LM (r = 0.36; p = 0.010) thickness. Moreover, the relative decrease (thinning) in the ST thickness was correlated with the relative increase in logarithmic decrement (i.e., decrease in soft tissue elasticity, r = -0.37, p = 0.011). The mechanical properties of the soft tissues were not related to their echogenicity. Discussion: In conclusion, the thicker the subcutaneous and perimuscular layers, the lesser the stiffness and the greater the time-dependent deformation to the external force of the tissues surrounding the LM during its relaxation and isometric contraction. Moreover, the greater the thinning of the ST and the thickening of the LM during its contraction, the higher the increase in lumbosacral tissue stiffness and the decrease in elasticity. Therefore, one should consider the thickness of the ST before planning or analyzing the outcomes of myotonometric or other external biomechanical measurements to avoid drawing the wrong conclusions about the mechanical properties of the myofascial tissue.

Lumbar multifidus muscle ultrasound imaging: Is handheld technology reliable?

BackgroundAdvancement in ultrasound imaging technology has led to the development of handheld devices that are more accessible to physical therapists due to decreased cost, reduced size, and improved ease of use relative to current established units. Physical therapists use ultrasound imaging of the lumbar multifidus muscle (LMM) to assist in rehabilitation of patients with lumbar pathology. ObjectivesTo identify the inter-device reliability of measuring the LMM thickness during a sustained contraction when comparing handheld (Butterfly iQ+) and established (SonoSite M-Turbo) ultrasound units. A secondary purpose was to determine the reliability of a student physical therapist using both devices. DesignA reliability measurement study MethodA blinded examiner identified the LMM at the L4 vertebral level and measured the thickness of the contracted muscle utilizing both the handheld and established ultrasound devices. ICC values were calculated to determine the inter-device and intra-rater reliability. ResultsThe study included 42 healthy participants, 30 females and 12 males, with a mean age of 38.5 years. The inter-device reliability during a sustained LMM contraction was excellent (ICC = 0.92, 95% CI: 0.87–0.94) and the intra-rater reliability was good for both the handheld (ICC = 0.85, 95% CI: 0.73–0.92) and established (ICC = 0.89, 95% CI: 0.82–0.93) ultrasound units. ConclusionResults support the use of handheld ultrasound by physical therapists and students to measure the LMM thickness. Future studies could investigate the reliability of handheld ultrasound in a variety of musculoskeletal and pathological structures important to PT practice.

Association of sagittal spinal alignment in the standing position with the masses and amounts of intramuscular non-contractile tissue of the trunk and lower extremity muscles in patients with Parkinson's disease

BackgroundWe examined the association of sagittal spinal alignment in the standing position with the masses and amounts of intramuscular non-contractile tissue of multiple trunk and lower extremity muscles, such as the hip joint muscles, measured using an ultrasound imaging device in patients with Parkinson's disease (PD). MethodsThe participants were 10 patients with PD. Sagittal spinal alignment (thoracic kyphosis, lumbar lordosis, and sacral anterior inclination angles) in the standing position was measured using a Spinal Mouse. Muscle thicknesses and echo intensities of the trunk and lower extremity muscles, including the hip joint muscles, were also measured in the prone or supine position using an ultrasound imaging device. FindingsPartial correlation analysis with body height and weight as control variables showed that a low lumbar lordosis angle in the standing position was significantly associated with low thicknesses of the trunk extensor muscles (lumbar erector spinae and multifidus). Partial correlation analysis also revealed that a high sacral anterior inclination angle in the standing position was significantly associated with low lumbar multifidus muscle thickness. However, the thicknesses and echo intensities of the trunk flexor and hip joint muscles were not significantly related to thoracic kyphosis, lumbar lordosis, or sacral anterior inclination angles. InterpretationThe results of this study suggested the association between a low lumbar lordosis angle in the standing position and low lumbar erector spinae and multifidus muscle thicknesses and between a high sacral anterior inclination angle in the standing position and low lumbar multifidus muscle thickness in patients with PD.

Mapping of lumbar multifidus stiffness Quantification in ankylosing spondylitis with shear-wave elastography

BackgroundLower back pain and stiffness are the typical symptoms of ankylosing spondylitis (AS). In this study, muscle mass was assessed by muscle density, mechanical elasticity, and area. We investigated the characteristics of lumbar paraspinal-muscle (PSM) mass using muscle ultrasound shear-wave elastography (SWE), as well as the validity of this method for identifying patients with AS.MethodsWe recruited a representative cohort of 30 AS patients, and 27 healthy volunteers who were age- and sex-matched to the patient study group, investigated the Young’s modulus (YM), cross-sectional area (CSA) and thickness of lumbar multifidus (LM) muscle using SWE. This study did not need to be randomized. Data were collected at the department of ultrasonography of Guangdong Provincial Hospital of Chinese Medicine. We analyzed the data using SPSS version 18.0 (IBM Corp, Armonk, NY, USA). Normal distribution was evaluated by the Shapiro–Wilk test and Q–Q plots. Demographic and baseline data will be analyzed with standard descriptive statistics. Data will be presented as the mean ± standard deviation (SD). Non-normally distributed data are presented as medians with interquartile ranges (IQR).ResultsYoung’s modulus (YM) of SWE in AS patients was significantly higher than that in volunteers. Percentage change in lumbar multifidus (LM) muscle cross-sectional area (CSA) and thickness were significantly lower in AS patients than in healthy volunteers on the left side of the body. Correlation analysis showed a positive correlation between percentage change in CSA and thickness in both volunteers and AS patients. In AS patients, YM was negatively correlated with percentage change of CSA and thickness on the right side, while increased disease duration in AS was associated with increased YM on the left.ConclusionAS patients showed reductions in LM muscle mass and function as the disease progressed, SWE could reflect these changes well.Trial registration.Chinese Clinical Trial Registry, ChiCTR2000031476. Registered 02/04/2020. http://www.chictr.org.cn/index.aspx.

Lumbar multifidus thickness changes during active leg raising with ultrasound imaging can detect patients with chronic non-specific low back pain

BackgroundAltered lumbar multifidus (LM) activation has been found in populations with non-specific chronic low back pain (NSCLBP). Objective: To detect differences in LM muscle thickness at rest and during active manoeuvres between patients with NSCLBP and pain-free controls and to analyze the ability of LM thickness change during the active straight leg raise (ASLR) with rehabilitative ultrasound imaging to detect patients with NSCLBP. DesignCross-sectional observational study. MethodsSeventy volunteers (50% patients NSCLBP) were recruited. 18 B-mode images of LM at L4-L5 or L5-S1 level selecting the most symptomatic level (both sides, six at rest and three during ASLR) were collected by a blinded assessor. Differences between patients and controls in LM muscle thickness at rest, during ASLR (holding 3sec), and 5 s after ASLR were calculated. In addition, discriminant validity was evaluated by calculating the area under the receiver operating characteristic curve (ROC), sensitivity, specificity and positive and negative likelihood ratio. ResultsSignificant LM thickness change differences during ASLR were found within and between groups: bilaterally, LM thickness change during ASLR was significantly higher in healthy controls than in NSCLBP patients. Ipsilateral LM muscle thickness change was sensitive to detect individuals with NSCLBP (ROC = 0.79–0.80). ConclusionPain-free individuals exhibited significantly greater LM thickness changes bilaterally during the ASLR compared to patients with NSCLBP. LM thickness change during the ASLR has good validity for discriminating patients with NSCLBP. Further studies should assess benefits of LM training programs in the management of these patients.

Effects of External Focus and Motor Control Training in Comparison with Motor Control Training Alone on Pain, Thickness of Trunk Muscles and Function of Patients with Recurrent Low Back Pain: A Single Blinded, Randomized Controlled Trial.

Recurrent low back pain (RLBP) affects different structures in the lumbar spine. Exercise therapy is highly recommended as one of the first-line treatments. One crucial variable introduced to enhance RLBP is the external focus. The present study aimed to investigate the effects of external focus training on pain, the thickness of transverse abdominis (TrA), internal oblique (IO), external oblique (EO), and lumbar multifidus (LM) muscles, kinesiophobia, fear-avoidance beliefs, and disability of people with RLBP. This randomized-controlled trial consisted of 38 RLBP patients. Patients were randomly divided into two groups the treatment group (n=19) that received external focus training in addition to motor control training and the control group (n=19) that received motor control training alone. The primary outcome was pain intensity, and secondary outcomes were the thickness of TrA, IO, EO, LM muscles, kinesiophobia, fear-avoidance beliefs, and disability that were measured at the baseline and after 16 sessions of interventions. The interventions were performed three sessions weekly. Reduction in pain intensity was more significant in the intervention group than in the control group (P<0.001, Cohen's d=-1.47). The thickness of TrA muscle in the contraction condition of the intervention group was significantly more on the left side (P<0.001, Cohen's d=1.05) than on the right side (P=0.03, Cohen's d=0.44). Other outcomes showed no significant differences. However, the Cohen's d effect size for the left IO (Cohen's d=0.57) and TKS (Cohen's d=-0.53) were moderate. In RLBP patients, external focus and motor control training could effectively reduce the pain. Although this intervention could increase the thickness of the TrA muscle of RLBP, it has no significant effect on the thickness of IO, EO, and LM muscles. In addition, the obtained results indicated that this intervention has no significant effect on kinesiophobia, fear-avoidance beliefs, and disability..

Asymmetry in internal oblique muscle thickness: Not the key to a cricket fast bowler's performance

Purpose Previous studies found that trunk muscle asymmetry may play a role in preventing injury in cricket fast bowlers, while the association with bowling performance has not been investigated. This study aims to describe the side-to-side differences in trunk muscle thickness and determine the association between bowling performance and these side-to-side differences in trunk muscle thickness in adolescent fast bowlers. Methods In this observational cross-sectional study, bowling performance, namely ball release speed and bowling accuracy, was recorded in adolescent fast bowlers. Ultrasound imaging measured external oblique, internal oblique, transversus abdominis and lumbar multifidus muscle thickness. Results Fast bowlers (n = 46) with a mean age of 15.9 (±1.2) years participated. On the non-dominant side, the external oblique and internal oblique at rest were thicker than on the dominant side (external oblique: p = 0.011, effect size = 0.27; internal oblique: p &lt; 0.0001, effect size = 0.40), while the transversus abdominus ( p = 0.72, effect size = 0.19) and lumbar multifidus ( p = 0.668, effect size = 0.04) were symmetrical. Weak correlations existed between bowling performance and the side-to-side differences in the thickness in all muscles, except for two moderate correlations: 1. The smaller the side-to-side difference in absolute thickness of the external oblique when contracted, the faster the ball release speed (Spearman's (ρ) = −0.455, p = 0.002). 2. Also, a smaller side-to-side difference in external oblique contraction ratio (Spearman's (ρ) = −0.495, p = 0.0001) was associated with faster ball release speed. Conclusions No relationship between bowling performance and side-to-side differences in internal oblique muscle thickness could be established, while more symmetrical external oblique muscles may be linked to faster ball release speeds.

Reliability of lumbar multifidus ultrasound assessment during the active straight leg raise test.

Previous evidence showed altered lumbar multifidus (LM) activation in populations with chronic nonspecific low back pain (LBP). We aimed to investigate the test-retest and inter-examiner reliability of ultrasound imaging (US) for assessing LM thickness at rest and activation during the active straight leg raise test (ASLR) and the association between thickness changes with clinical outcomes. Fifty-two patients with LBP and two examiners (one experienced and one novice) participated in this study. A total of 18 B-mode images at L4-L5 or L5-S1level (both sides, 3 at rest and 6 during ASLR) were collected. For assessing test-retest reliability, the experienced examiner repeated the procedure after 7days. Intraclass correlation coefficients (ICC), standard error of measurements (SEM) and minimal detectable changes (MDC) were calculated. Inter-examiner agreement was good to excellent (ICC3,2=0.71-0.92) and test-retest reliability was excellent (ICC3,1= 0.91-0.98). Mean average of multiple measurements improved the agreement. Greater LM thickness at rest (p<.05) and greater thickness change after 3s (p<.01) and 10s (homolateral side, p<.01; contralateral side, p<.05) were associated with less pain intensity. US is a reliable method to assess the LM thickness at rest and contracted during the ASLR in patients with LBP. The measurement at 3s after maintaining ASLR, as well as the use of the mean of three measurements, has been shown to be the most reliable method for measuring LM muscle thickness during ASLR.

Sensorimotor system changes in adolescent rugby players post-concussion: A prospective investigation from the subacute period through to return-to-sport

BackgroundThe pathophysiology of concussion is complex. Altered sensorimotor function post-concussion may contribute to the wide range of symptoms and impairments reported. There is currently limited evidence documenting changes in sensorimotor function during the recovery period. The aim of this study was to investigate the effect of concussion on the sensorimotor system in adolescents post-concussion using a multifaceted approach. Study designProspective nested case-control study. MethodsA total of 285 male adolescent rugby players underwent assessment of sensorimotor function during preseason. Players who sustained a concussion during the season and control players, matched for age and playing position, were assessed in the subacute period (3–5 days) and after return-to-sport (3 weeks). Tests of sensorimotor function included balance, cervical spine and vestibulo-ocular function, and measurement of the size and contraction of lumbopelvic muscles (ultrasound imaging). ResultsTwenty-three players (8%) sustained a concussion. Of these, 20 players were assessed during the subacute period and 17 players following return-to-sport. The prevalence of vestibulo-ocular dysfunction increased from 38.9% to 72.2% during the subacute period and dysfunction was present in 83.3% of players after return-to-sport (p = 0.01). Changes in lumbar multifidus muscle size (p = 0.002) and thickness (p = 0.05) at the L5 vertebral level were observed. No statistically significant changes in balance, cervical spine proprioception, or contraction of lumbopelvic muscles were found (p > 0.05). ConclusionChanges in sensorimotor function were observed in the subacute period post-concussion, with some persisting after return-to-sport. Using symptom-based criteria for return-to-sport may not adequately reflect the sequelae of concussion on the sensorimotor system.

Association of sagittal spinal alignment in the sitting position with the trunk and lower extremity muscle masses in children and adults with cerebral palsy: A pilot study

BackgroundWe examined the association of sagittal spinal alignment in the sitting position with the trunk and lower extremity muscle masses in children and adults with cerebral palsy (CP). We also compared muscle masses between children and adults with CP who could and could not sit without the support of their upper extremities. MethodsThe subjects were 34 children and adults with CP. Sagittal spinal alignment in the sitting position, such as thoracic kyphosis, lumbar lordosis, and sacral anterior inclination angles were measured using a Spinal Mouse. The thicknesses of the trunk and lower extremity muscles were measured using an ultrasound imaging device. Furthermore, the subjects were classified into the sitting-possible group (n = 18), who could sit without the support of the upper extremities, or a sitting-impossible group (n = 16), who could not sit without the support of the upper extremities. FindingsStepwise regression analysis revealed that the lumbar multifidus muscle thickness and body weight were significant and independent factors of the lumbar lordosis angle in the sitting position. The thicknesses of the thoracic erector spinae, gluteus maximus and minimus, long head of the biceps femoris, semitendinosus, and rectus femoris muscles were significantly lower in the sitting-impossible group than those in the sitting-possible group. InterpretationDecreased lumbar lordosis angle in the sitting position was associated with decreased lumbar multifidus muscle mass in children and adults with CP. Furthermore, not only trunk extensor but also hip joint muscles may contribute to sitting without upper extremity support.

Does Neuromuscular Electrical Stimulation Have an Additive Effect on Disability, Pain and Abdominal and Lumbar Muscle Thickness in Chronic Low Back Pain? – A Randomized Controlled Double-Blind Study

Abstract Objective To examine the effect of neuromuscular electrical stimulation (NMES) combined with core stabilization exercises (CSE) in patients with chronic low back pain (CLBP). Methods Thirty-six patients (mean age 33.6±12.6 years) with CLBP were randomly assigned to 4 weeks (12 sessions) of NMES group (NMES combined with CSE) (n=18) vs. Control group (sham NMES and CSE) (n=18). After the 4 weeks, same exercises were given as home exercise program without NMES. The outcome measures were Oswestry Disability Index (ODI), Visual Analog Scale (VAS), Nottingham Health Profile (NHP) and ultrasonography. Ultrasonography was used for measuring transversus abdominis (TrA), internal oblique (IO), external oblique (EO) muscles thickness and lumbar multifidus muscle thickness and area. Assessments were performed at baseline and 4th week and eighth week follow-up. Results In both groups, the change of ODI, VAS and NHP values of the first measurement according to the values of the 4th week and the eighth week were found statistically significant (p=0.001; p&lt;0.01). There were no statistically significant differences in ODI, VAS and NHP scores between the 4th week and the eighth week in both groups (p&gt;0.05). None of NMES and control group measurements with US showed a statistically significant increase in the TrA, IO, EO thickness and multifidus thickness and area (p&gt;0.05). Conclusions It was shown that NMES can be tolerated by patients with CLBP, but the addition of simultaneus NMES to CSE had no contribution to the clinical outcome measures.

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.

Combined neuromuscular electrical stimulation with motor control exercise can improve lumbar multifidus activation in individuals with recurrent low back pain

Motor control exercise (MCE) is commonly prescribed for patients with low back pain. Although MCE can improve clinical outcomes, lumbar multifidus muscle (LM) activation remains unchanged. Neuromuscular electrical stimulation (NMES) can be used to re-activate motor units prior to MCE which should result in increased LM activation. Therefore, this study aimed to explore the immediate effects of NMES combined with MCE on LM activation and motor performance. Twenty-five participants without low back pain (NoLBP) and 35 participants with movement control impairment (MCI) were recruited. Participants with MCI were further randomized to combined NMES with MCE (COMB) or sham-NMES with MCE (MCE) group. Ultrasound imaging was used to measure LM thickness at rest, maximum voluntary isometric contraction (MVIC), and NMES with MVIC. These data were used to calculate LM activation. Quadruped rocking backward was used to represent motor performance. LM activation and motor performance were measured at baseline and after one-session of intervention. Results showed that both COMB and MCE groups had significantly lower (P < 0.05) LM activation compared with NoLBP group at baseline. Additionally, both COMB and MCE groups demonstrated significant improvement (P < 0.05) in motor performance while COMB group demonstrated significantly greater improvement (P < 0.05) in LM activation compared with MCE group. Individuals with MCI still have persisting LM activation deficit. Our key findings suggest that combined NMES and MCE may have better ability to improve LM activation in individuals with MCI. These findings would support the utility of NMES to induce a priming effect before MCE.

Reliability of lumbar multifidus and iliocostalis lumborum thickness and echogenicity measurements using ultrasound imaging.

To establish the test-retest and inter-rater reliability of lumbar multifidus (LM) and iliocostalis lumborum (IL) muscle thickness and echogenicity as derived using ultrasound imaging. Ultrasound images of the LM and IL were collected from 11 healthy participants on two occasions, 1week apart, by two independent assessors. Measures of LM and IL thickness and echogenicity were subject to test-retest and inter-rater reliability, which was assessed by calculation of an F statistic, the interclass correlation coefficient (ICC), the standard error of measurement, 95% confidence intervals and Bland-Altman plots. This study was given approval by The University of Melbourne Behavioural and Social Sciences Human Ethics Sub-Committee (ref: 1749845). Assessors A and B showed good to excellent test-retest reliability for LM thickness (ICC3,3 A: 0.89 and B: 0.98), LM echogenicity (ICC3,3 A: 0.93 and B: 0.95) and IL echogenicity (ICC3,3 A: 0.87 and B: 0.83). Test-retest reliability for IL thickness was poor for Assessor A but excellent for Assessor B. Both assessors demonstrated excellent inter-rater reliability for LM thickness and echogenicity (ICC2,3: 0.79 and 0.94), but poor reliability for IL thickness and echogenicity (ICC2,3: 0.00 and 0.39). Inter-rater and test-retest reliability was excellent for LM but was less reliable for measures of the IL muscle.

Impacts of Different Sitting Positions on Lumbar Multifidus Muscle Thickness and Hardness: A Crossover Comparative Study

Impacts of Different Sitting Positions on Lumbar Multifidus Muscle Thickness and Hardness: A Crossover Comparative Study

Recovery of the lumbar multifidus muscle size in chronic low back pain patients by strengthening hip abductors: A randomized clinical trial

IntroductionDecrease in cross-sectional thickness of lumbar multifidus (MF) muscles during prolonged low back pain episodes commonly occurs. Restoration of the MF muscle size can be an effective way of treating chronic low back pain (CLBP) patients. Traditionally, clinicians apply muscle stabilization exercises for these patients. Recent studies support the need for active strengthening exercises for treatment of the CLBP patients. ObjectiveThe MF muscles provide lumbar stability, and therefore we hypothesized that strengthening of these muscles can be more effective than the MF muscle stabilization exercises in restoration of the muscle size. DesignStudy design was a randomized allocation control trial with two groups of adult female CLBP patients (n = 12 each; age range of 20–45). Patients in the control group underwent stabilization exercises and the patients in the intervention group underwent the hip abductor strengthening exercises. SettingFor all subjects of each group, the trials continued in 24 sessions distributed over 8 weeks and the MF muscles were measured in the beginning of the first session and one week after completion of the last session. Main outcome measuresStatistical significance (p-value) of the change in the average MF muscle thickness, pain, and disability scores along with for each group were estimated. ResultsBoth regimens of exercises can significantly decrease the pain and disability: average pain and disability reductions of 46% (p-value of 0.001) and 33% (p-value of 0.02) via stabilization versus average pain and disability reductions of 65% (p-value of 0.001) and 59% (p-value of 0.001) via hip abductor strengthening. However, the hip abductor strengthening is the sole statistically significant exercise regimen (p-value of 0.014 vs 0.94) for increasing the MF muscle size. ConclusionReplacement of the traditional stabilization exercises with the hip abductor strengthening exercises for effective treatment of female adults with CLBP is recommended.

Seasonal Changes in Lumbar Multifidus Muscle in University Rugby Players.

Although smaller lumbar multifidus muscle (LMM) was reported to be a strong predictor of lower limb injury (LLI) in Australian Football League players, LMM morphology has not been investigated in rugby athletes. This study examined seasonal changes in LMM in rugby players and whether LMM characteristics were associated with low back pain (LBP) and LLI. Ultrasound examinations of the LMM were acquired in 21 university-level rugby players (12 women, 9 men) at preseason and end-season. LMM cross-sectional area (CSA), thickness at rest, and thickness during submaximal contraction (e.g., contralateral arm lift) measurements in prone and standing were obtained bilaterally at the L5-S1 level. The percent change in LMM thickness during contraction was calculated as follows: [(thicknesscontracted - thicknessrest)/thicknessrest × 100]. Self-reported questionnaires were used to acquire data on LBP and LLI. There was no significant difference in LMM characteristics between preseason and end-season measurements (P > 0.05). Preseason LMM CSA, side-to-side CSA asymmetry, and thickness at rest or during contraction were not associated with LBP or LLI. However, a lower percent thickness change in the standing position was significantly associated with having LBP during the preseason (P = 0.01) and playing season (P = 0.001), as well as LLI during the preseason (P = 0.03). This study provides preliminary evidence that LMM contractile ability and behavior during functional movement, such as standing, may have important implications for the susceptibility to injury among rugby athletes.