The assessment of abdominal and multifidus muscles and their role in physical function in older adults: 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.

The assessment of paraspinal muscle epimuscular fat in participants with and without low back pain: A case-control study

It remains unclear whether paraspinal muscle fatty infiltration in low back pain (LBP) is i) solely intramuscular, ii) is lying outside the epimysium between the muscle and fascial plane (epimuscular) or iii) or combination of both, as imaging studies often use different segmentation protocols that are not thoroughly described. Epimuscular fat possibly disturbs force generation of paraspinal muscles, but is seldomly explored. This project aimed to 1) compare epimuscular fat in participants with and without chronic LBP, and 2) determine whether epimuscular fat is different across lumbar spinal levels and associated with BMI, age, sex and LBP status, duration or intensity. Fat and water lumbosacral MRIs of 50 chronic LBP participants and 41 healthy controls were used. The presence and extent of epimuscular fat for the paraspinal muscle group (erector spinae and multifidus) was assessed using a qualitative score (0-5 scale; 0 = no epimuscular fat and 5 = epimuscular fat present along the entire muscle) and quantitative manual segmentation method. Chi-squared tests evaluated associations between qualitative epimuscular fat ratings and LBP status at each lumbar level. Bivariate and partial spearman's rho correlation assessed relationships between quantitative and qualitative epimuscular fat with participants' characteristics. Epimuscular fat was more frequent at the L4-L5 (X2 = 13.781, p = 0.017) and L5-S1 level (X2 = 27.825, p < 0.001) in participants with LBP compared to controls, which was not found for the higher lumbar levels. The total qualitative score (combined from all levels) showed a significant positive correlation with BMI, age, sex (female) and LBP status (r = 0.23-0.55; p < 0.05). Similarly, the total area of epimuscular fat (quantitative measure) was significantly correlated with BMI, age and LBP status (r = 0.26-0.57; p < 0.05). No correlations were found between epimuscular fat and LBP duration or intensity. Paraspinal muscle epimuscular fat is more common in chronic LBP patients. The functional implications of epimuscular fat should be further explored.

Effect of aquatic exercise versus standard care on paraspinal and gluteal muscles morphology in individuals with chronic low back pain: a randomized controlled trial protocol

BACKGROUND

Low back pain (LBP) is one of the most disabling diseases and a major health issue. Despite the evidence of a link between paraspinal and gluteal muscle dysfunction and LBP, it is unknown whether aquatic exercises can lead to improvements in paraspinal and gluteal muscle morphology and function, and whether improvements in overall muscle health are associated with improvements in patients' outcomes. The unique properties of water allow a water-based exercise program to be tailored to the needs of those suffering from LBP. This study uses magnetic resonance imaging (MRI) to investigate the effect of an aquatic exercise program versus standard exercise on 1) paraspinal and gluteal muscle size, quality and strength and 2) pain, disability, and psychological factors (pain related fear, depression, anxiety, sleep quality) in chronic LBP.

METHODS

This study will include 34 participants with chronic non-specific LBP and moderate to severe disability, aged between 18 and 65, who will be randomly assigned (1:1) to the aquatic exercise group or land-based standard care exercise group. Both groups will receive 20 supervised sessions, twice per week over 10 weeks. MRIs will be obtained along the lumbosacral spine (L1-L5) and pelvis at the start and end of the intervention to assess the effect of each exercise intervention on paraspinal and gluteal muscle size and quality. Pre- to post-intervention changes in all outcomes between each group will be assessed, and the association between the changes in back muscle quality and clinical outcomes will be examined. Between-subjects repeated measure analysis of variance will be used to examine the changes in paraspinal muscle morphology over the different time points. Linear mixed models will be used to assess whether baseline scores can modify the response to the exercise therapy treatment.

DISCUSSION

This study will determine if water-based exercises targeting the lower back and gluteal muscles can lead to important changes in muscle quality and function, and their possible relation with patients' pain and functional improvements. Our findings will have strong clinical implications and provide preliminary data to design a community program to better support individuals with chronic LBP.

TRIAL REGISTRATION

NCT05823857, registered prospectively on April 27th, 2023.

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

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

Transversus Abdominis Ultrasound Thickness during Popular Trunk-Pilates Exercises in Young and Middle-Aged Women

The transversus abdominis (TrA) is a core muscle that contributes to functional mobility and lumbar stability. This study aimed to compare the changes in TrA thickness during different Pilates exercises, and to identify the exercise that elicited the greatest TrA activation. Forty-four healthy women were divided into two groups: young (25-35 years old) and middle-aged (36-55 years old). TrA thickness was assessed by ultrasound while the participants performed five Pilates exercises: basic position, hundred, hip roll, side plank, and dead bug. A repeated measures analysis of variance revealed that the dead bug exercise induced a significantly higher increase in TrA thickness (relative to rest) than the other exercises (p < 0.05). The young group also showed a significantly higher overall TrA thickness than the middle-aged group (p < 0.05). The findings suggest that the dead bug exercise is the most effective for enhancing TrA activation among the Pilates exercises tested. The basic position and the hundred exercises can be used as warm-up exercises before performing more challenging exercises such as the hip roll, the side plank, and the dead bug. The sequence of exercises can be similar for both young and middle-aged women.

Lumbar multifidus muscle morphology is associated with low back-related pain duration, disability, and leg pain: A cross-sectional study in secondary care

BACKGROUND

Systematic reviews and studies exploring associations between morphologic change of paraspinal muscles and low back pain or related outcomes such as disability, radiculopathy, and physical workload, have reported conflicting results. This study explores the associations between lumbar multifidus muscle quality and clinical outcomes relating to low back pain.

METHODS

Cross-sectional study of spinal clinic outpatients presenting with a primary complaint of low back and/or leg symptoms. Univariable and multivariable regression models were used to investigate associations between MRI-based multifidus muscle cross-sectional area at L4 and L5 and clinical outcomes for low back pain, leg pain, disability, restricted motion, and strenuous nature of work. Results were reported with β-coefficients, odds ratios (OR), or incidence rate ratios (IRR) and their corresponding 95% confidence intervals, based on a 10% difference in muscle quality for each clinical variable. Multivariable analyses were adjusted for age, sex, and BMI.

RESULTS

875 patients [487 females; mean (SD) age: 43.6 (10.2) years] were included. In the multivariable analyses, muscle quality was significantly associated with disability (0-23 scale) [β: -0.74, 95% CI: -1.14, -0.34], leg pain intensity (0-10 scale) [β: -0.25, 95% CI: -0.46, -0.03], and current pain duration of more than 12 months [OR: 1.27, 95% CI: 1.03, 1.55]. No associations were found for low back pain intensity, morning stiffness, painful active range of motion, or work nature.

CONCLUSIONS

Patients with higher lumbar multifidus muscle quality reported lower levels of low back pain-related disability and leg pain intensity, indicating that muscle quality may play a role in the etiology of lumbar spine disorders. However, the clinical importance of these associations is uncertain due to the low magnitude of identified associations. Future longitudinal studies are needed to understand the effect of lumbar multifidus muscle quality on lumbar-related pain and disability.

Computed tomography-based preoperative muscle measurements as prognostic factors for anastomotic leakage following oncological sigmoid and rectal resections

BACKGROUND

Oncological sigmoid and rectal resections are accompanied with substantial risk of anastomotic leakage. Preoperative risk assessment and patient selection remain difficult, highlighting the importance of finding easy-to-use parameters. This study evaluates the prognostic value of contrast-enhanced (CE) computed tomography (CT)-based muscle measurements for predicting anastomotic leakage.

METHODS

Patients that underwent oncological sigmoid and rectal resections in the LUMC between 2016 and 2020 were included. Preoperative CE-CT scans, were analyzed using Vitrea software to measure total abdominal muscle area (TAMA) and total psoas area (TPA). Muscle areas were standardized using patient's height into: psoas muscle index (PMI) and skeletal muscle index (SMI) (cm2 /m2 ).

RESULTS

In total 46 patients were included, of which 13 (8.9%) suffered from anastomotic leakage. Patients with anastomotic leakage had a significantly lower PMI (22.1 vs. 25.1, p < 0.01) and SMI (41.8 vs. 46.6, p < 0.01). After adjusting for confounders (age and comorbidity), lower PMI (odds ratio [OR]: 0.85, 95% confidence interval [CI] 0.71-0.99, p = 0.03) and SMI (OR: 0.93, 95%CI 0.86-0.99, p = 0.02) were both associated with anastomotic leakage.

CONCLUSION

This study showed that lower PMI and SMI were associated with anastomotic leakage. These results indicate that preoperative CT-based muscle measurements can be used as prognostic factor for risk stratification for anastomotic leakage.

Thigh and Calf Myosteatosis are Strongly Associated with Muscle and Physical Function in African Caribbean Men

BACKGROUND

African Caribbeans have higher levels of myosteatosis than other populations; however, little is known about the impact of myosteatosis on physical function in African Caribbeans. Herein, we examined the association between regional myosteatosis of the calf, thigh, and abdomen versus physical function in 850 African-Ancestry men aged 64.2 ± 8.9 (range 50-95) living on the Caribbean Island of Tobago.

METHODS

Myosteatosis was measured using computed tomography and included intermuscular adipose tissue (IMAT) and muscle density levels of the thigh, calf, psoas, and paraspinous muscles. Outcomes included grip strength, time to complete 5 chair-rises, and 4-meter gait speed. Associations were quantified using separate linear models for each myosteatosis depot and were adjusted for age, height, demographics, physical activity, and chronic diseases. Beta coefficients were presented per standard deviation of each myosteatosis depot.

RESULTS

Higher thigh IMAT was the only IMAT depot significantly associated with weaker grip strength (β = -1.3 ± 0.43 kg, p = .003). However, lower muscle density of all 4 muscle groups was associated with weaker grip strength (all p < .05). Calf and thigh myosteatosis (IMAT and muscle density) were significantly associated with both worse chair rise time and gait speed (all p < .05), whereas psoas IMAT and paraspinous muscle density were associated with gait speed.

CONCLUSION

Myosteatosis of the calf and thigh-but not the abdomen-were strongly associated with grip strength and performance measures of physical function in African Caribbean men. However, posterior abdominal myosteatosis may have some utility when abdominal images are all that are available.

Evaluation of the degeneration of the multifidus and erector spinae muscles in patients with low back pain and healthy individuals

BACKGROUND

Although several studies have been conducted to determine the cause of low back pain (LBP), a sufficient correlation has not been found between research findings and symptoms. Therefore there seems to be a need for studies to explain the relationship between pain and morphological changes in the paraspinal muscles of patients with LBP through comparisons with healthy control subjects.

OBJECTIVE

The aim of this study was to examine degeneration in the lumbar musculus multifidus (LMF) and lumbar musculus erector spinae (LES) muscles in patients with chronic LBP with non-radiculopathy lumbar disc herniation (LDH), patients with mechanical LBP, and healthy individuals.

METHODS

The study included 35 patients with mechanical LBP, 38 patients with non-radiculopathy LDH, and a control group of 36 healthy participants. In all patients and the control group, evaluations were made on axial magnetic resonance imaging slices at L3-S1 level of the LMF and LES cross-sectional areas (CSA), total CSA (TCSA = LMF+LES), fat infiltrations and asymmetries.

RESULTS

The mean CSA values of the right and left LMF and LES showed significant differences between the groups (p< 0.001, p= 0.002, p= 0.002, p= 0.010, respectively). Fat infiltrations showed a difference between the right-left LMF and left LES groups (p= 0.007, p< 0.001, p= 0.026, respectively). Asymmetry was not observed between the CSA and TCSA of the right and left sides.

CONCLUSION

A correlation was found between fat infiltration in the LMF and mechanical LBP and LDH. However, no significant correlation was determined between LBP and the CSA and TCSA of the LMF and LES. This was thought to be due to an incorrect result of CSA and TCSA in the evaluation of muscle mass. Therefore, for a more accurate evaluation of muscle mass, it can be considered necessary to measure muscle atrophy associated with fat infiltration or functional CSA.

The Role of Multifidus in the Biomechanics of Lumbar Spine: A Musculoskeletal Modeling Study

BACKGROUND

The role of multifidus in the biomechanics of lumbar spine remained unclear.

PURPOSE

This study aimed to investigate the role of multifidus in the modeling of lumbar spine and the influence of asymmetric multifidus atrophy on the biomechanics of lumbar spine.

METHODS

This study considered five different multifidus conditions in the trunk musculoskeletal models: group 1 (with entire multifidus), group 2 (without multifidus), group 3 (multifidus with half of maximum isometric force), group 4 (asymmetric multifidus atrophy on L5/S1 level), and group 5 (asymmetric multifidus atrophy on L4/L5 level). In order to test how different multifidus situations would affect the lumbar spine, four trunk flexional angles (0°, 30°, 60°, and 90°) were simulated. The calculation of muscle activation and muscle force was done using static optimization function in OpenSim. Then, joint reaction forces of L5/S1 and L4/L5 levels were calculated and compared among the groups.

RESULTS

The models without multifidus had the highest normalized compressive forces on the L4/L5 level in trunk flexion tasks. In extreme cases produced by group 2 models, the normalized compressive forces on L4/L5 level were 444% (30° flexion), 568% (60° flexion), and 576% (90° flexion) of upper body weight, which were 1.82 times, 1.63 times, and 1.13 times as large as the values computed by the corresponding models in group 1. In 90° flexion, the success rate of simulation in group 2 was 49.6%, followed by group 3 (84.4%), group 4 (89.6%), group 5 (92.8%), and group 1 (92.8%).

CONCLUSIONS

The results demonstrate that incorporating multifidus in the musculoskeletal model is important for increasing the success rate of simulation and decreasing the incidence of overestimation of compressive load on the lumbar spine. Asymmetric multifidus atrophy has negligible effect on the lower lumbar spine in the trunk flexion posture. The results highlighted the fine-tuning ability of multifidus in equilibrating the loads on the lower back and the necessity of incorporating multifidus in trunk musculoskeletal modeling.

The relationship between the degeneration and asymmetry of the lumbar multifidus and erector spinae muscles in patients with lumbar disc herniation with and without root compression

BACKGROUND

The determination of muscle pathologies in lumbar disc herniation (LDH) and other conditions with low back pain is important for understanding low back problems and determining appropriate treatment methods. In patients with lumbar disc herniation with radiculopathy, elucidating the effect of root compression on the severity of muscle degeneration may predict the importance of alleviating root compression. For this purpose, magnetic resonance imaging (MRI) was used to compare the degeneration and asymmetries of the lumbar musculus multifidus (MF) and lumbar musculus erector spinae (ES) muscles in patients with lumbar discopathy without root compression (radiculopathy) and in patients with lumbar discopathy with root compression (radiculopathy).

METHODS

The patients were examined in two groups: 56 patients with lumbar discopathy and no radiculopathy (Non-rad group) and 51 patients with lumbar discopathy and radiculopathy (Rad group). On axial MRI sections passing through the centre of the disc at the L3-S1 level, the asymmetry, cross-sectional area (CSA), fat infiltration, and total CSA (TCSA = MF + ES) of the MF and ES muscles were measured and compared.

RESULTS

No difference was seen between the groups with respect to the CSA values of the right and left MF and left ES, but a significant difference was found in the right ES CSA (p = 0.021). The CSA and TCSA of the MF and ES showed no asymmetry according to group. Severe fat infiltration of > 50% in the right and left MF and left ES was found in the Rad group at a higher rate than in the Non-rad group. Fat infiltration was significantly positively correlated with age, body mass index, and the duration of pain (p < 0.001, p < 0.001, p = 0.004, respectively).

CONCLUSIONS

The study results showed a correlation between LDH and paraspinal muscle degeneration, while no correlation was found with asymmetry. Severe (> 50%) fat infiltration is associated with root compression, and the severity of fat filtration increases in the presence of root compression. The development of more severe degeneration due to denervation associated with root compression plays a role in the emergence of this situation. Therefore, in patients with lumbar disc herniation with radiculopathy, it can be foreseen that to stop and correct severe fat infiltration and muscle degeneration, first, nerve root compression should be corrected with appropriate medical treatment methods, and in patients in whom there is no response, the pressure should be alleviated with appropriate surgical methods.

Low lumbar multifidus muscle status and bone mineral density are important risk factors for adjacent segment disease after lumbar fusion: a case–control study

Background

The quantity and quality of the paraspinal muscles are important factors that lead to spinal diseases. However, the role of paraspinal muscles in the pathogenesis of adjacent segment disease (ASD) after lumbar fusion surgery is rarely studied. The purpose of the research is to investigate the relationship between paraspinal muscles and ASD.

Methods

Thirty-three patients with ASD were included, and 33 controls without ASD were matched according to the basic demographic information. Cross-sectional images of the paraspinal muscles at each intervertebral disk level (L1–S1) before the first operation were analyzed, and the cross-sectional area (CSA) and degree of fat infiltration (FI) of the multifidus (MF) muscle and the erector spinae muscle were compared.

Results

There was no significant difference in demographic characteristics (P > 0.05) except for the bone mineral density (BMD) (P = 0.037) between the two groups. There were significant differences in the CSA and FI of the lower lumbar multifidus (P < 0.05). The CSA of the MF muscle at L3–L4, FI of the MF muscle at L4–L5 and L5–S1 and BMD were important risk factors for ASD. Among patients who received two-segment fusion for the first time, significant difference was observed in the degree of FI of the MF muscle in the lower lumbar segment (P < 0.05).

Conclusions

The CSA, FI and BMD of the lower lumbar MF muscle were closely related to the occurrence of ASD. The CSA of the MF muscle at L3–L4, the degree of FI of the MF muscle at L4–L5 and L5–S1 and BMD were important risk factors for ASD. The number of fusion segments in the first operation has a certain impact on the above-mentioned conclusions.

Protocol and reference values for minimal detectable change of MyotonPRO and ultrasound imaging measurements of muscle and subcutaneous tissue

The assessment of muscle health is of paramount importance, as the loss of muscle mass and strength can affect performance. Two non-invasive tools that have been found to be useful in this are the MyotonPRO and rehabilitative ultrasound imaging, both have shown to be reliable in previous studies many of which conducted by the research team. This study aims to determine the reliability of previously unassessed local body structures and to determine their minimal detectable changes (MDC) to support both researchers and clinicians. Twenty healthy participants were recruited to determine the reliability of seven skin positions out of a previously established protocol. Reliability was determined between three independent raters, and day to day reliability was assessed with one rater a week apart. Intraclass Correlation Coefficients (ICC) between raters and between days for tissue stiffness, tone and elasticity range from moderate to excellent (ICC 0.52–0.97), with most good or excellent. ICCs for subcutaneous thickness between days was good or excellent (ICC 0.86–0.91) and moderate to excellent between raters (ICC 0.72–0.96), in muscles it was moderate to excellent between raters and days (ICC 0.71–0.95). The protocol in this study is repeatable with overall good reliability, it also provides established MDC values for several measurement points.

Age- and sex-dependent differences in the morphology and composition of paraspinal muscles between subjects with and without lumbar degenerative diseases

BACKGROUND

The quality of the paraspinal muscles has been recommended as a surrogate marker for the evaluation of the severity of the lumbar degenerative diseases (LDD). The purpose of this study is to determine the age- and sex-dependent differences in the morphology and composition of the paraspinal muscles between LDD and asymptomatic subjects.

METHODS

We analyzed data from 370 patients and 327 asymptomatic volunteers aged between 18-85 years. The measurement of the cross-sectional area (CSA) of the erector spinae, multifidus, and psoas at the L4/5-disc level was performed by the magnetic resonance imaging (MRI). The fatty infiltration ratio (FI %) of the multifidus and erector spinae was calculated.

RESULTS

FI % of the lumbar paraspinal muscles were significantly and positively correlated with the severity of LDD instead of the CSA. Males had greater CSA than females, and females showed higher FI % than males in the paraspinal muscles. With the increase of age, the CSA of the lumbar paraspinal muscles gradually decreased, and the psoas showed the most significant decreasing trend. However, the FI % gradually increased in both LDD and asymptomatic groups with aging.

CONCLUSION

Age- and sex-dependent differences were found in the morphology and composition of the paraspinal muscles between subjects with and without LDD. Further long-term follow up investigations and basic studies will continue to confirm the natural history of the paraspinal muscles with aging and their association with LDD.

Paraspinal muscle imaging measurements for common spinal disorders: review and consensus-based recommendations from the ISSLS degenerative spinal phenotypes group

PURPOSE

Paraspinal muscle imaging is of growing interest related to improved phenotyping, prognosis, and treatment of common spinal disorders. We reviewed issues related to paraspinal muscle imaging measurement that contribute to inconsistent findings between studies and impede understanding.

METHODS

Three key contributors to inconsistencies among studies of paraspinal muscle imaging measurements were reviewed: failure to consider possible mechanisms underlying changes in paraspinal muscles, lack of control of confounding factors, and variations in spinal muscle imaging modalities and measurement protocols. Recommendations are provided to address these issues to improve the quality and coherence of future research.

RESULTS

Possible pathophysiological responses of paraspinal muscle to various common spinal disorders in acute or chronic phases are often overlooked, yet have important implications for the timing, distribution, and nature of changes in paraspinal muscle. These considerations, as well as adjustment for possible confounding factors, such as sex, age, and physical activity must be considered when planning and interpreting paraspinal muscle measurements in studies of spinal conditions. Adoption of standardised imaging measurement protocols for paraspinal muscle morphology and composition, considering the strengths and limitations of various imaging modalities, is critically important to interpretation and synthesis of research.

CONCLUSION

Study designs that consider physiological and pathophysiological responses of muscle, adjust for possible confounding factors, and use common, standardised measures are needed to advance knowledge of the determinants of variations or changes in paraspinal muscle and their influence on spinal health.

Factors associated with paravertebral muscle cross-sectional area in patients with chronic low back pain

Background

This study was performed to reveal the relationships between the cross-sectional areas (CSAs) of the paraspinal muscles and the severity of low back pain (LBP), including the level of disability.

Methods

This single-center cross-sectional study was conducted on 164 patients with chronic LBP. The effects of demographic characteristics, posture, level of physical activity, disc herniation type, and sarcopenia risk on the CSAs of paraspinal muscles were evaluated along with the relationship between the CSAs and severity of pain and disability in all patients. The CSAs of paraspinal muscles were evaluated using the software program Image J 1.53.

Results

A negative significant correlation was found between age and the paraspinal muscle’s CSA (P < 0.05), whereas a positive correlation was present between the level of physical activity and the CSA of the paraspinal muscle at the L2-3 and L3-4 levels. The CSAs of paraspinal muscles in patients with sarcopenia risk was significantly lower than those in patients without sarcopenia risk (P < 0.05). The CSAs of paraspinal muscles at the L2-3 and L3-4 levels in obese patients were significantly higher than those in overweight patients (P = 0.028, P = 0.026, respectively). There was no relationship between the CSAs of paraspinal muscles and pain intensity or disability.

Conclusions

Although this study did not find a relationship between paraspinal CSAs and pain or disability, treatment regimens for preventing paraspinal muscles from atrophy may aid pain physicians in relieving pain, restoring function, and preventing recurrence in patients with chronic LBP.

Are computed tomography-based measures of specific abdominal muscle groups predictive of adverse outcomes in older cancer patients?

PURPOSE

It is unknown whether computed tomography (CT)-based total abdominal muscle measures are representative of specific abdominal muscle groups and whether analysis of specific abdominal muscle groups are predictive of the risk of adverse outcomes in older cancer patients.

METHODS

Retrospective single-center cohort study in elective colon cancer patients aged ≥65 years. CT-based skeletal muscle (SM) surface area, muscle density and intermuscular adipose tissue (IMAT) surface area were determined for rectus abdominis; external- and internal oblique and transversus abdominis (lateral muscles); psoas; and erector spinae and quadratus lumborum (back muscles). Outcomes were defined as severe postoperative complications (Clavien-Dindo score >2) and long-term survival (median follow-up 5.2 years).

RESULTS

254 older colon cancer patients were included (median 73.6 years, 62.2% males). Rectus abdominis showed the lowest SM surface area and muscle density and the back muscles showed the highest IMAT surface area. Psoas muscle density, and lateral muscle density and percentage IMAT were associated with severe postoperative complications independent of gender, age and cancer stage.

CONCLUSIONS

CT-based total abdominal muscle quantity and quality do not represent the heterogeneity that exists between specific muscle groups. The potential added value of analysis of specific muscle groups in predicting adverse outcomes in older (colon) cancer patients should be further addressed in prospective studies.

Multifidus muscle fatty infiltration as an index of dysfunction in patients with single-segment degenerative lumbar spinal stenosis: A case-control study based on propensity score matching

The multifidus muscle morphology and its relation to the function of patients with degenerative lumbar spinal stenosis (DLSS) remains unclear. This study aimed to investigate the multifidus muscle morphology in patients with DLSS and to determine its relations to the patients function. Sixty-two patients with single-segment DLSS at L4-5 and sixty control patients with non-spinal-derived low back pain were retrospectively enrolled and further matched based on propensity scores. The Oswestry Disability Index (ODI) and bodily pain using the Short-Form Health Survey were evaluated. The cross-sectional area (CSA), CSA of fatty free (CSAF), and fatty infiltration rate [FIR; i.e., (1- CSAF/CSA) × 100%] of the multifidus muscle were measured on magnetic resonance images using ImageJ software. Adjustment for confounders was performed using generalized linear models. The FIR at L5-S1 in controls was statistically significant but slightly less than the DLSS group. The between-groups difference was 5% (p < 0.001), and 2.8% (p = 0.036) in the complete and matching cohorts, respectively, after adjustment. Statistically significant differences were not observed in other multifidus muscle parameters between the groups. FIR > 20% at L5-S1 was independently associated with ODI ≥ 41 in patients with DLSS [Retaining demography as control block or not, Odds ratio (OR) = 8.4, p = 0.023; OR = 12.3, p = 0.030]. The multifidus muscle at L5-S1 demonstrated slightly greater fatty infiltration in patients with L4-5 single-segment DLSS than controls. Significant fatty infiltration in the multifidus muscle at L5-S1 may be correlated with poor function in patients with L4-5 single-segment DLSS.

Reliability of a Test for Assessment of Isometric Trunk Muscle Strength in Elderly Women

Objective

The aim of this study was to analyze the reproducibility of a protocol using the maximal isometric strength test of the trunk in elderly women aged above 60 years, without low back pain.

Methods

Twenty-one physically inactive elderly women, who had not engaged in any activity or exercise program in the past three months, participated in the cross-sectional study that consisted of two days of evaluations for the maximal isometric strength of the extensor and flexor muscles of the trunk, with a 48 h interval between the sessions. A platform with fixed seating was used, which allowed the fixation of the hip and lower limbs, with a load cell connected to a linear encoder. To verify the reliability of the test, the interclass correlation coefficient, variation coefficient, minimum detectable difference (MDD), standard error of measurement, and Bland–Altman graphs were calculated.

Results

No statistical difference was observed between the first and second evaluation, which indicates that there was no learning effect. Interclass correlation coefficient values were classified as very high and high for extensor (0.98) and flexor (0.86) muscles, respectively, besides low variation (9% for both muscle groups) and acceptable values for minimum detectable difference (extensors = 51.1 N, flexors = 48.9 N). In addition, the Bland–Altman analysis revealed low bias and values within the limits of agreement.

Conclusion

It is concluded that the test of maximum isometric strength of the trunk in healthy and trained elderly people presents high reliability. These values proved to be reliable if performed in at least two evaluation sessions, which confirms the hypothesis of the authors by the consistency of the measurement test.

Imaging with ultrasound in physical therapy: What is the PT's scope of practice? A competency-based educational model and training recommendations

Physical therapists employ ultrasound (US) imaging technology for a broad range of clinical and research purposes. Despite this, few physical therapy regulatory bodies guide the use of US imaging, and there are limited continuing education opportunities for physical therapists to become proficient in using US within their professional scope of practice. Here, we (i) outline the current status of US use by physical therapists; (ii) define and describe four broad categories of physical therapy US applications (ie, rehabilitation, diagnostic, intervention and research US); (iii) discuss how US use relates to the scope of high value physical therapy practice and (iv) propose a broad framework for a competency-based education model for training physical therapists in US. This paper only discusses US imaging—not ‘therapeutic’ US. Thus, ‘imaging’ is implicit anywhere the term ‘ultrasound’ is used.

Trunk exercise training improves muscle size, strength, and function in older adults: A randomized controlled trial

The aim of this study was to assess the effectiveness of a multimodal exercise program to increase trunk muscle morphology and strength in older individuals, and their associated changes in functional ability. Using a single-blinded parallel-group randomized controlled trial design, 64 older adults (≥60 years) were randomly allocated to a 12-week exercise program comprising walking and balance exercises with or without trunk strengthening/motor control exercises; followed by a 6-week walking-only program (detraining; 32 per group). Trunk muscle morphology (ultrasound imaging), strength (isokinetic dynamometer), and functional ability and balance (6-Minute Walk Test; 30 second Chair Stand Test; Sitting and Rising Test; Berg Balance Scale, Multi-Directional Reach Test; Timed Up and Go; Four Step Square Test) were the primary outcome measures. Sixty-four older adults (mean [SD]; age: 69.8 [7.5] years; 59.4% female) were randomized into two exercise groups. Trunk training relative to walking-balance training increased (mean difference [95% CI]) the size of the rectus abdominis (2.08 [1.29, 2.89] cm² ), lumbar multifidus (L4/L5:0.39 [0.16, 0.61] cm; L5/S1:0.31 [0.07, 0.55] cm), and the lateral abdominal musculature (0.63 [0.40, 0.85] cm); and increased trunk flexion (29.8 [4.40, 55.31] N), extension (37.71 [15.17, 60.25] N), and lateral flexion (52.30 [36.57, 68.02] N) strength. Trunk training relative to walking-balance training improved 30-second Chair Stand Test (5.90 [3.39, 8.42] repetitions), Sitting and Rising Test (1.23 [0.24, 2.23] points), Forward Reach Test (4.20 [1.89, 6.51] cm), Backward Reach Test (2.42 [0.33, 4.52] cm), and Timed Up and Go Test (-0.76 [-1.40, -0.13] seconds). Detraining led to some declines but all outcomes remained significantly improved when compared to pre-training. These findings support the inclusion of trunk strengthening/motor control exercises as part of a multimodal exercise program for older adults.

Collection of the Abstracts of the 2019Sp PMD: Translational Myology and Mobility Medicine

The Interdepartmental Research Centre of Myology (CIR-Myo), Department of Biomedical Sciences, University of Padova, Italy and the A&C M-C Foundation for Translational Myology, Padova, Italy organized with the scientific support of Helmut Kern, Jonathan C. Jarvis, Viviana Moresi, Marco Narici, Feliciano Protasi, Marco Sandri and Ugo Carraro, the 2019SpringPaduaMuscleDays: Translational Myology and Mobility Medicine, an International Conference held March 28-30, 2019 in Euganei Hills and Padova (Italy). Presentations and discussions of the Three Physiology Lectures and of the seven Sessions (I: Spinal Cord Neuromodulation and h-bFES in SC; II: Muscle epigenetics in aging and myopathies; III: Experimental approaches in animal models; IV: Face and Voice Rejuvenation; V: Muscle Imaging; VI: Official Meeting of the EU Center of Active Aging; VII: Early Rehabilitation after knee and hip replacement) were at very high levels. This was true in the past and will be true in future events thanks to researchers and clinicians who were and are eager to attend the PaduaMuscleDays.

Population-based study of age- and sex-related differences in muscle density and size in thoracic and lumbar spine: the Framingham study

Relative age-related deficit in trunk muscle density was greater in women than men whereas the relative decrease in muscle mass with age was similar in both sexes. The greater muscle fat content and greater age-related fat accumulation among women may contribute to women suffering more functional disabilities than men.

INTRODUCTION

A better understanding of the effect of aging on trunk musculature will have implications for physical function, disability, pain, and risk of injury in older adults. Thus, we determined the age- and sex-related differences in muscle density and size of both thoracic and lumbar trunk muscles.

METHODS

In this cross-sectional study, muscle density and size were measured from quantitative computed tomography (QCT) scans for 10 trunk muscle groups at different vertebral levels in 250 community-based men and women aged 40 to 90 years from the Framingham Offspring and Third Generation cohorts.

RESULTS

Trunk muscles in men were 20-67% larger and had 5-68% higher density than in women. The relative age-related deficits in muscle size were similar in both sexes, and decreased on average by ~ 8% per decade in both sexes. In contrast, women had greater age-related decreases in muscle density than men (- 17% in women, and - 11% in men, p < 0.01). Age-related declines varied by specific muscle, tending to be greater for outer trunk muscles than for paraspinal muscles, but within a given muscle the age-related changes in muscle density and size were similar among spinal levels.

CONCLUSION

This comprehensive study of trunk muscle deficits with increasing age may have important implications for physical function, disability, pain, and risk of injury in older adults. The greater levels of mobility impairments with aging in women may in part be explained by greater proportion of intramuscular fat tissue and greater age-related fat accumulation in trunk muscles in women than in men.

The Association between Imaging Parameters of the Paraspinal Muscles, Spinal Degeneration, and Low Back Pain

This narrative review investigated imaging parameters of the paraspinal muscles and their association with spinal degenerative features and low back pain (LBP) found in the literature. Three principal signs of muscle degeneration were detected on imaging: decreased muscle size, decreased radiographic density, and increased fat deposits. Men have a higher density of paraspinal muscles than women, younger individuals have a higher density than older ones, and lean individuals have a higher density than those with an increased body mass index. Fatty infiltration appears to be a late stage of muscular degeneration and can be measured noninvasively by an MRI scan. Fatty infiltration in the lumbar multifidus is common in adults and is strongly associated with LBP, especially in women, independent of body composition. Fatty infiltration develops in areas where most degenerative changes are found. MR spectroscopy studies have corroborated that the lumbar multifidus in LBP subjects has a significantly higher fat content than asymptomatic controls. There is a strong need for establishing uniform methods of evaluating normal parameters and degenerative changes of the paraspinal muscles. Additional imaging studies are needed to improve the understanding of the association and causal relationships between LBP, spinal degeneration, and changes in the paraspinal muscles.