Impact of Multifidus Muscle Morphometry on the Clinical Evolution of Chronic Low Back Pain

Purpose: The multifidus muscle is an important extensor muscle of the lumbar spine. It plays a major role in the stability and realization of axial rotation movements of the thoraco-lumbar spine. Its atrophy by fatty degeneration would be at the origin of the occurrence of chronic low back pain which constitutes a public health problem in Senegal. Taking into account its anatomy is essential for the etiopathogenic analysis and the treatment of low back pain. The purpose of our work was to investigate the impact of multifidus muscle morphometry on the anatomy-clinical evolution of low back pain. Material and method: this was a prospective study over a period of 30 months from November 2019 to May 2022. It involved 100 patients seen in the neurology department of Fann Hospital for chronic low back pain and who had already had a scanner falling within the criteria for low back pain. We used 3D Slicer, SPSS 20, Excel 2016 software to model and analyze the morphometric data of the multifidus muscle after physiotherapy and control lumbar scans. Results: The sex ratio was 2.23. The average age of the patients was 45 ± 7 years. On the initial CT scan, according to the Hadar classification, we noted a predominance of grade 2 with 56% in L5/S1, followed by grade 1 with 32% and grade 3 with 14%. In L4/L5, the majority of patients, 67%, had grade 1. A conflicting circumferential disc bulge with the roots predominating in L5/S1 was present in 94% of men (p-value = 0.02). Before physiotherapy, the average volume of the multifidus was 193 mm3 ± 39, after physiotherapy it was 203 mm3 ± 42 with a progression rate of 5.2%. Clinically, severe type pain had regressed from 86% before physiotherapy to 0% after physiotherapy (p-value = 0.03). Conclusion: Taking into account the morphometry of the multifidus is an essential element in the management of chronic low back pain.

Slacklining as therapy to address non-specific low back pain in the presence of multifidus arthrogenic muscle inhibition

Low back pain(LBP)represents the most prevalent,problematic and painful of musculoskeletal conditions that affects both the individual and society with health and economic concerns.LBP is a heterogeneous condition with multiple diagnoses and causes.In the absence of consensus definitions,partly because of terminology inconsistency,it is further referred to as non-specific LBP(NSLBP).In NSLBP patients,the lumbar multifidus(MF),a key stabilizing muscle,has a depleted role due to recognized myocellular lipid infiltration and wasting,with the potential primary cause hypothesized as arthrogenic muscle inhibition(AMI).This link between AMI and NSLBP continues to gain increasing recognition.To date there is no‘gold standard’or consensus treatment to alleviate symptoms and disability due to NSLBP,though the advocated interventions are numerous,with marked variations in costs and levels of supportive evidence.However,there is consensus that NSLBP management be cost-effective,self-administered,educational,exercise-based,and use multi-modal and multi-disciplinary approaches.An adjuvant therapy fulfilling these consensus criteria is‘slacklining’,within an overall rehabilitation program.Slacklining,the neuromechanical action of balance retention on a tightened band,induces strategic indirect-involuntary therapeutic muscle activation exercise incorporating spinal motor control.Though several models have been proposed,understanding slacklining’s neuro-motor mechanism of action remains incomplete.Slacklining has demonstrated clinical effects to overcome AMI in peripheral joints,particularly the knee,and is reported in clinical case-studies as showing promising results in reducing NSLBP related to MF deficiency induced through AMI(MF-AMI).Therefore,this paper aims to:rationalize why and how adjuvant,slacklining therapeutic exercise may positively affect patients with NSLBP,due to MF-AMI induced depletion of spinal stabilization;considers current understandings and interventions for NSLBP,including the contributing role of MF-AMI;and details the reasons why slacklining could be considered as a potential adjuvant intervention for NSLBP through its indirect-involuntary action.This action is hypothesized to occur through an over-ride or inhibition of central down-regulatory induced muscle insufficiency,present due to AMI.This subsequently allows neuroplasticity,normal neuro-motor sequencing and muscle re-activation,which facilitates innate advantageous spinal stabilization.This in-turn addresses and reduces NSLBP,its concurrent symptoms and functional disability.This process is hypothesized to occur through four neuro-physiological processing pathways:finite neural delay;movement-control phenotypes;inhibition of action and the innate primordial imperative;and accentuated corticospinal drive.Further research is recommended to investigate these hypotheses and the effect of slacklining as an adjuvant therapy in cohort and control studies of NSLBP populations.

Paraspinal strength and electromyographic fatigue in patients with sub-acute back pain and controls:Reliability,clinical applicability and between-group differences

BACKGROUND Paraspinal muscle strength and fatigue are considered important in low back pain(LBP)prevention and rehabilitation.High reliability of paraspinal strength and electromyographic(EMG)-fatigue parameters has not been universally reported.Moreover,the discriminative validity of these parameters requires further exploration,under the threat of potentially poor reliability of the methods examined.AIM To investigate the reliability and discriminative validity of paraspinal strength and EMG-related fatigue in subjects with recurrent LBP and healthy participants.METHODS Test-retest measurements were performed in 26 healthy and 66 LBP volunteers,for reliability.Paraspinal isometric maximal and mean strength were determined with a maximum voluntary isometric contraction(MVIC)protocol,performed in a custom-made device.For the fatigue test,participants performed a 60% MIVC level continuous isometric contraction of the paraspinals,in conjunction with EMG analysis from 4 muscle sites of the lumbar spine.Initial median frequency(IMF),the median frequency slope(MFslope),as well as the root mean square(RMS)slope EMG parameters were used as fatigue measures.Data were analysed with repeated measures ANOVA for test-retest differences.For reliability,the intraclass correlation coefficient(ICC3,1),standard error of the measurement(SEM)and the smallest detectable difference(SDD)were reported.Group-related differences for fatigue measures were analysed with a Multivariate Analysis of Covariance,with age,weight and strength as covariates.RESULTS Isometric strength presented statistically significant between-day differences(P<0.01),however these did not exceed 10%(healthy:7.2%/LBP-patients:9.7%)and ICC reliability values were excellent,yet test-retest error was increased for the patient group(healthy:ICC3,1:0.92-0.96,SEM:5.72-5.94 Hz,SDD:18.51%-18.57%/LBP-patients:ICC3,1:0.91-0.96,SEM:6.49-6.96,SDD:30.75%-31.61%).For the frequency data,IMF reliability was excellent(healthy:ICC3,1:0.91-0.94,SEM:3.45-7.27 Hz,SDD:9.56%-20.14%/patients:ICC3,1:0.90-0.94,SEM:6.41-7.59 Hz,SDD:17.75%-21.02%)and of MF raw and normalised slopes was good(healthy:ICC3,1:0.78-0.82,SEM:4.93-6.02 Hz,SDD:13.66-16.67%/LBP-patients:ICC3,1:0.83-0.85,SEM:6.75-7.47 Hz,SDD:18.69%-20.69%).However,the reliability for RMS data presented unacceptably high SDD values and were not considered further.For discriminative validity,less MVIC and less steep MFslopes were registered for the patient group(P<0.01).CONCLUSION Reliability and discriminative ability of paraspinal strength and EMG-related frequency parameters were demonstrated in healthy participants and patients with LBP.

Possibility of a Novel Warm-Up Strategy Using Capacitive and Resistive Electric Transfer: A Pilot Study

[Purpose] Capacitive and resistive electric transfer (CRET) is becoming prevalent in sports settings. CRET is effective for improving pain and healing injured tissue;however, its influence on muscle function and morphology is still unclear. This study confirmed the immediate effects of CRET on the duration of muscular stiffness and range of motion (ROM). [Method] This study describes the protocol for a single-arm trial with the non-blinding of participants and researchers. Twenty-four healthy men participated in the study. They received CRET therapy for their low back areas. The muscular stiffness of the multifidus muscle (superficial and deep) and the ROM using the active straight leg raise (ASLR) test were measured pre-intervention, post-intervention (immediately), and 15 and 30 min post-intervention. We compared these parameters using a one-way analysis of variance and Dunnett’s test (multiple comparison tests for subtests). [Results] The muscular stiffness of the superficial and deep multifidus muscles was significantly decreased, and the ASLR test showed a significant increase compared with the test performed pre-intervention. In addition, these effects persisted for 30 min. [Conclusion] Warm-up is vital for improving muscular stiffness and increasing the ROM. CRET is a useful device for achieving these aims, particularly as a passive warm-up method in sports settings.

Quantification Threshold Pixel Technique of Magnetic Resonance Imaging in Paraspinal Muscles Atrophy among Discopathy Patients

Purpose: To evaluate the relationship between lumbosacral discopathy status and paraspinal atrophic changes (Cross-sectional area (CSA) and fatty infiltration (FI)) among different age groups. Materials and Methods: We retrospectively evaluated 200 patients with confirmed discopathy who were examined by lumbosacral Magnetic Resonance Imaging (MRI) at the two main governmental hospitals in Gaza Strip. Using ImageJ software and quantification threshold technique, we measured the CSA and FI of paraspinal muscles {multifidus (MF) & erector spinae (ES)}. The interpretation of MRI images was performed by two radiologists with a good inter-observer agreement between the radiological discopathy findings. Results: The highest percentage and severity of discopathy were noticed at the level of L4/5 (89.5%), followed by L5/S1 (14.5%). The FI is increased towards lower levels of L3/4 to L5/S1. No correlation was found between discopathy level, the severity of discopathy, and CSA of MF & ES muscles. In contrast, a correlation was observed between FI of MF & ES muscles, discopathy level, and severity. Also, the results illustrated no significant relation was observed between CSA of MF & ES muscles and age groups (P > 0.05), while a significant correlation was reported between FI and age groups (P Conclusion: The MRI quantification threshold pixel technique for paraspinal muscles reflected the atrophic changes like CSA and FI in discopathy patients.