Lumbar Multifidus Muscle Thickness Research Articles

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.

Using neuromuscular electrical stimulation in conjunction with ultrasound imaging technique to investigate lumbar multifidus muscle activation deficit

Lumbar multifidus muscle (LM) activation deficit has been proposed as a potential underlying mechanism responsible for recurrence episode of low back pain (LBP). The quantification of voluntary LM activation can provide a better understanding of the role of muscle activation deficit in LBP. The objective of this technical report is to propose a new approach using neuromuscular electrical stimulation (NMES) in combination with the ultrasound imaging technique (USI) to investigate the ability of individual to voluntarily activate the LM. We recruited ten participants with a recurrent LBP (rLBP) and twelve participants with no history of LBP (NoLBP). Theoretically, the superimposition of NMES on the LM during maximum voluntary isometric contraction (MVIC) should activate all motor units available in the LM. The percentage of LM activation (%LM) can be calculated by the changes of LM thickness during MVIC, divided by the changes of LM thickness during the combination of MVIC and NMES. This %LM was used to compare between groups. The individuals with rLBP had significantly lower %LM (p < 0.05) compared with the NoLBP counterpart (%LM = 72.4 and 92.9, respectively). Results demonstrate that this new approach can potentially differentiate %LM among individuals with rLBP and NoLBP. This new approach can be potentially used to 1) determine the extent of LM activation deficit, 2) identify the existence of muscle activation deficit in the LM, and 3) objectively measure the effect of the intervention designed to address the LM activation deficit.

Reliability of B-mode ultrasonography to measure lumbar multifidus muscle dimensions in patients with unilateral lumbar disc herniation

ObjectivesTo evaluate Ultrasound Imaging (USI) reliability for measurement of lumbar multifidus (LMF) muscle thickness and cross sectional area (CSA) at rest and during contraction in patients with unilateral lumbar disc herniation. SettingLaboratory. DesignReliability Study. ParticipantsThirty patients, aged 25–50 years (37.55 ± 9.55), with unilateral L4-L5 lumbar disc herniation participated in this study. Main outcome measuresThickness and CSA of LMF were measured using B-mode ultrasound by two raters in prone position. ResultsSame day and multiple day inter-rater and same day intra-rater reliability showed good to excellent reliability (intraclass correlation coefficients ranged from 0.70 to 0.91). Also standard error of measurement and minimal detectable change for USI reliabilities ranged from 0.06 to 0.57 and 0.16 to 1.31, respectively. ConclusionsReliability of USI for measurements of LMF muscle thickness and CSA was high, and consistent with previous studies conducted on reliability of USI to measure LMF dimensions in other populations.

Reliability of Ultrasound Imaging of the Trunk Musculature in Athletes with and without Hamstring Injuries.

Trunk muscles play an important role in providing both mobility and stability during dynamic tasks in athletes. The purpose of this study was to evaluate the within-day and between-day reliability of ultrasound (US) in measuring abdominal and lumbar multifidus muscle (MF) thickness in athletes with and without hamstring strain injury (HSI). Fifteen male soccer players (18-30 years old) with and without HSI were evaluated using two US probes (50 mm linear 7.5 MHZ and 70 mm curvilinear 5 MHz). The abdominal muscle thickness as well as the cross sectional area (CSA) of the MF was measured. To determine within and between days reliabilities, the second and third measurements were repeated with two hours and one week intervals, respectively. Intraclass correlation coefficients for athletes with and without HSI demonstrated good to high reliability for the abdominal muscle thickness (0.82 and 0.93) and CSA of the MF muscle (0.84 and 0.89, respectively). Our results indicated that US seemed to be a reliable instrument to measure abdominal and lumbar multifidus muscle thickness in soccer players with and without HSI. However, further studies are recommended to support the present study findings in other athletes.

Does Plantar Pressure Distribution Influence the Lumbar Multifidus Muscle Thickness in Asymptomatic Individuals? A Preliminary Study

BackgroundAtrophy can occur in the lumbar multifidus (LM) muscle quickly as a result of various musculoskeletal problems. Knowing factors influencing muscle thickness of the LM will provide important clues about lumbopelvic stability. ObjectivesAlthough there are several studies in the literature investigating the adverse effects of foot–ankle postural disorders on the lumbopelvic region, to our knowledge there has been no investigation of plantar pressure distribution (PPD) as a factor influencing muscle thickness of the LM. The aim of this study was to determine whether PPD could affect LM muscle thickness. MethodsThis observational study consisted of 25 asymptomatic individuals. Ultrasonographic imaging was used to determine the thickness of the LM. All participants were subjected to PPD analysis using the Digital Biometry Scanning System and Milletrix software in 9 different plantar pressure zones. The Pearson product-moment correlation coefficients were used to examine the correlations between the LM muscle thickness and other variables. Stepwise multiple linear regression analysis was used to determine the variables with the greatest influence on LM muscle thickness. ResultsPeak pressures of medial and lateral zones of the heel were the significant and independent factors influencing static LM thickness, with 39.5% of the variance; moreover, the peak pressures of heel medial and fourth metatarsal bone were the significant and independent factors influencing dynamic LM thickness, with 38.7% of the variance. ConclusionsPlantar pressure distribution could be an important factor influencing LM thickness, although further research is required. Examining foot–ankle biomechanics may provide information about the stability of the LM.

The effect of low back pain and lower limb injury on lumbar multifidus muscle morphology and function in university soccer players

BackgroundThe lumbar multifidus muscle (LMM) plays a critical role to stabilize the spine. While low back pain (LBP) is a common complaint in soccer players, few studies have examined LMM characteristics in this athletic population and their possible associations with LBP and lower limb injury. Therefore, the purpose of this study was to 1) investigate LMM characteristics in university soccer players and their potential association with LBP and lower limb injury; 2) examine the relationship between LMM characteristics and body composition measurements; and 3) examine seasonal changes in LMM characteristics.MethodsLMM ultrasound assessments were acquired in 27 soccer players (12 females, 15 males) from Concordia University during the preseason and assessments were repeated in 18 players at the end of the season. LMM cross-sectional area (CSA), echo-intensity and thickness at rest and during contraction (e.g. function) were assessed bilaterally in prone and standing positions, at the L5-S1 spinal level. A self-reported questionnaire was used to assess the history of LBP and lower limb injury. Dual-energy x-ray absorptiometry (DEXA) was used to acquire body composition measurements.ResultsSide-to-side asymmetry of the LMM was significantly greater in males (p = 0.02). LMM thickness when contracted in the prone position (p = 0.04) and LMM CSA in standing (p = 0.02) were also significantly greater on the left side in male players. The LMM % thickness change during contraction in the prone position was significantly greater in players who reported having LBP in the previous 3-months (p < 0.001). LMM CSA (r = − 0.41, p = 0.01) and echo-intensity (r = 0.69, p < 0.001) were positively correlated to total % body fat. There was a small decrease in LMM thickness at rest in the prone position over the course of the season (p = 0.03).ConclusionsThe greater LMM contraction in players with LBP may be a maladaptive strategy to splint and project the spine. LMM morphology measurements were correlated to body composition. The results provide new insights with regards to LMM morphology and activation in soccer players and their associations with injury and body composition measurements.

Ultrasonography of Lumbar Multifidus Muscle in University American Football Players.

The primary objective of this study was to examine and compare lumbar multifidus (LM) muscle size, asymmetry, and function in university football players with and without low back pain (LBP). A secondary objective was to examine the relationship between LM characteristics and body composition in football players. Ultrasound assessments of the LM muscle were performed in 41 university football players during the preseason. LM muscle cross-sectional area, echo intensity (e.g., indicator of fatty infiltration and connective tissue), thickness at rest, and thickness during submaximal contraction (e.g., contralateral arm lift) measurements in prone and standing positions were obtained bilaterally at the L5-S1 level. Body composition measures were acquired using dual-energy x-ray absorptiometry. A self-administered questionnaire was used to obtain LBP history data. The LM muscle thickness at rest in prone and in standing was significantly smaller in football players who reported the presence of LBP in the previous 3 months. The LM cross-sectional area in prone was significantly and positively correlated with weight, height, lean body mass, total fat mass, and total percent body fat. LM echo intensity was strongly correlated with total percent body fat and total fat mass and negatively correlated with the percent thickness change during contraction. The results of this study provide novel information on LM muscle morphology and activation in football players in prone and standing and suggest that players with LBP in the previous 3 months had smaller LM muscle thickness. LM morphology was strongly correlated with body composition measurements.

P.171 Effects of Korean dementia simulation program for caregivers of the elderly with dementia pilot study

Atrophy can occur in the lumbar multifidus (LM) muscle quickly as a result of various musculoskeletal problems. Knowing factors influencing muscle thickness of the LM will provide important clues about lumbopelvic stability.Although there are several studies in the literature investigating the adverse effects of foot–ankle postural disorders on the lumbopelvic region, to our knowledge there has been no investigation of plantar pressure distribution (PPD) as a factor influencing muscle thickness of the LM. The aim of this study was to determine whether PPD could affect LM muscle thickness.This observational study consisted of 25 asymptomatic individuals. Ultrasonographic imaging was used to determine the thickness of the LM. All participants were subjected to PPD analysis using the Digital Biometry Scanning System and Milletrix software in 9 different plantar pressure zones. The Pearson product-moment correlation coefficients were used to examine the correlations between the LM muscle thickness and other variables. Stepwise multiple linear regression analysis was used to determine the variables with the greatest influence on LM muscle thickness.Peak pressures of medial and lateral zones of the heel were the significant and independent factors influencing static LM thickness, with 39.5% of the variance; moreover, the peak pressures of heel medial and fourth metatarsal bone were the significant and independent factors influencing dynamic LM thickness, with 38.7% of the variance.Plantar pressure distribution could be an important factor influencing LM thickness, although further research is required. Examining foot–ankle biomechanics may provide information about the stability of the LM.

Associations of Trunk Muscle Thickness and Muscle Strength in Healthy Male Adults

Background: Since the test of muscle strength needs a person’s maximum exertion, the objective assessment of muscle size is often used. Among the imaging techniques for assessing muscle size, muscle thickness is easy to measure by ultrasonography. However, little is known about the associations of trunk muscle thickness and muscle strength. Objectives: This study aimed to investigate the correlation between trunk muscle thickness and muscle strength. Methods: Seventeen healthy male university students participated in this study (20.8 ± 0.6 years). Abdominal (rectus abdominis, external oblique, internal oblique, transverse abdominis) and low back (lumbar erector spinae, lumbar multifidus) muscle thickness were measured at rest using B-mode ultrasonography. Maximum voluntary isometric trunk flexion, extension, and rotation torque were measured using dynamometers. The relationships between all tested variables were investigated using the Pearson’s correlation coefficient. Results: A significant positive correlation was found between flexion and extension torque (r = 0.664, P = 0.004), flexion and right rotation torque (r = 0.565, P = 0.018), flexion and left rotation torque (r = 0.641, P = 0.006), extension and right rotation torque (r = 0.844, P < 0.001), extension and left rotation torque (r = 0.784, P < 0.001), and between right and left rotation torque (r = 0.982, P < 0.001). However, there was no significant correlation between trunk muscle thickness and torque. Conclusions: This study provides basic information about trunk muscle thickness and muscle strength in healthy male adults. The associations of trunk muscle thickness and muscle strength could not be identified through our measurements.

The effect of diaphragm training on lumbar stabilizer muscles: a new concept for improving segmental stability in the case of low back pain.

PurposeThe aim of this study was to assess the effects of diaphragm training on low back pain and thickness of stabilizer muscles of the lumbar spine.Patients and methodsFifty-two individuals were recruited with a history of chronic low back pain in our randomized controlled trial. The participants were divided randomly into two groups. One of the groups took part in a complex training program and completed with diaphragm training (DT group, n=26). The control (C) group took part only in the complex training (n=21). The thickness of transversus abdominis, diaphragm, and lumbar multifidus muscle was measured with ultrasonography in two positions: lying and sitting. All muscles were assessed in relaxed and in contracted state in the lying position and in a relatively relaxed (calm sitting) and relatively contracted state (during weightlifting) in the sitting position.ResultsAfter the training, severity of the pain was significantly reduced in both the groups. Regarding the thickness of the muscles, there were no changes in group C. The thickness of transversus abdominis increased significantly in relaxed and in relatively relaxed state, but there were no changes in contracted and relatively contracted state in group DT. As for the diaphragm muscle, there were significant increase in the state of supine position and in relatively contracted state, but there was no notable change in relatively relaxed state. With regard to the thickness of lumbar multifidus, a significant increase was only found in the left-sided muscle in relaxed, relatively relaxed, and relatively contracted state and in case of the right-sided one in relatively contracted state in group DT.ConclusionOur results suggest that diaphragm training has an effect also on the thickness of other active stabilizers of the lumbar spine, such as transversus abdominis and lumbar multifidus muscles.

The Effects of an 8-Week Stabilization Exercise Program on Lumbar Multifidus Muscle Thickness and Activation as Measured With Ultrasound Imaging in Patients With Low Back Pain: An Exploratory Study

BackgroundLumbar stabilization exercise programs (LSEP) produce positive effects on clinical outcomes, but the underlying mechanisms remain relatively unexplored. Psychological and neuromuscular mechanisms can be involved, such as a better activation of the lumbar multifidus, which represents one possibility. ObjectivesTo determine the following: (1) the effect of an LSEP on lumbar multifidus muscle thickness and activation, as measured with rehabilitative ultrasound imaging (RUSI), in patients with low back pain (LBP); (2) the correlation between RUSI measures and any change in clinical outcomes following the LSEP; and (3) the reliability of RUSI measures in control subjects over 8 weeks. DesignOne-arm clinical trial with healthy subjects as a control group; reliability study. SettingLSEP delivered in a clinical setting; outcomes measured in a laboratory setting. ParticipantsA total of 34 patients with nonacute LBP and 28 healthy control subjects. MethodsOutcomes were measured before and after an 8-week LSEP in patients with LBP, and at the same time interval (without treatment, to assess reliability) in control subjects. Main Outcome MeasurementsPain numeric rating scale, Oswestry Disability Index (function), as well as RUSI measures for the lumbar multifidus (LM) muscles at 3 vertebral levels (L5-S1, L4-5, and L3-4) during rest (static) and dynamic contractions (percent thickness change). ResultsPatients did not show systematic changes in RUSI measures relative to controls, even though RUSI impairments were observed at baseline (dynamic measure at L5-S1) and even though patients had significant improvements in pain and disability. Correlational analyses with these clinical outcomes suggested that patients had reduced muscle thickness at baseline that was associated with a greater reduction in disability following LSEP; however, LM activation measured at baseline showed the opposite. Static RUSI measures showed excellent reliability at the L4-5 and L3-4 levels, whereas dynamic measures were not reliable. ConclusionsPatients showed less muscle activation than controls at baseline (L5-S1 level), but the LSEP did not normalize this impairment. The links between RUSI measures and the change in clinical outcomes during LSEP should be further explored.This clinical trial has been recorded in the International Standard Registered Clinical/soCial sTudy Number (ISRCTN) registry (ID: ISRCTN94152969). Level of EvidenceII

The effects of pelvic diagonal movements and resistance on the lumbar multifidus

[Purpose] The purpose of this study was to compare the effects of pelvic diagonal movements, made with and without resistance, on the thickness of lumbar multifidus muscles. [Subjects and Methods] Participants in this study were healthy subjects who had no musculoskeletal disorders or lumbar-related pain. Participants were positioned on their side and instructed to lie with their hip flexor at 40 degrees. Ultrasonography was used for measurement, and the values of two calculations were averaged. [Results] The thickness of ipsilateral lumbar multifidus muscles showed a significant difference following the exercise of pelvic diagonal movements. The results of anterior elevation movements and posterior depression movements also demonstrated significant difference. There was no significant difference in lumbar multifidus muscles thickness between movements made with and without resistance. [Conclusion] These findings suggest that pelvic diagonal movements can be an effective method to promote muscular activation of the ipsilateral multifidus. Furthermore, researchers have concluded that resistance is not required during pelvic diagonal movements to selectively activate the core muscles.

Test-retest reliability of measurements of abdominal and multifidus muscles using ultrasound imaging in adults aged 50–79 years

Test-retest reliability of the combined process of ultrasound imaging (USI) and image measurement of thickness of abdominal and upper lumbar multifidus (MF) muscles and MF cross sectional area (CSA) of older adults has not been established. Imaging muscles of older adults can be challenging due to age-related changes in the spine and skeletal muscle so establishing test-retest reliability in this population is important. This study aimed to evaluate test-retest reliability of USI of abdominal and MF muscle thickness and MF CSA for adults aged 50–79 years. One operator took single sets of ultrasound images of abdominal and MF muscles of 23 adults aged 50–79 years participating in a clinical trial of vitamin D supplementation for knee osteoarthritis, on two occasions, one week apart. Images were subsequently measured by a single examiner. Test-retest reliability for abdominal muscle thickness and MF CSA was substantial (intraclass correlation coefficients (ICC) > 0.81) and for MF thickness ranged from fair to substantial (ICC 0.55–0.86). The standard error of measurement (SEM) was low (0.02–0.21) in every case. ICCs were low and SEM values were high for percentage thickness change. The substantial test-retest reliability of abdominal and MF (L4-L5) muscle thickness and of MF CSA supports the use of USI as a clinical and research tool to assess abdominal and MF muscle thickness and MF CSA of older adults.

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

Background: Spinal stabilisation exercise has been shown to be effective in the rehabilitation of low back pain (LBP). Due to the isometric nature of spinal stabilisation exercise, manual therapists use various verbal instructions to elicit lumbar multifidus muscle contraction.Objectives: The purpose of this study was to assess whether or not three verbal instructions would alter muscle thickness of the lumbar multifidus muscle differently in asymptomatic individuals and patients with LBP.Methods: Three verbal instructions were selected for this study: (1) swell the muscle underneath the transducer, (2) draw your belly button in towards your spinal column and (3) think about tilting your pelvis but without really doing it. Lumbar multifidus muscle thickness was determined using parasagittal ultrasound (US) imaging. Measurements of muscle thickness were collected at rest and during verbal instructions from 21 asymptomatic adults and 21 patients with LBP. Percent changes of muscle thickness during contraction and at rest were compared between groups and across verbal instructions.Results: ANOVA results showed no significant interaction for both L4-5 and L5-S1, but a significant main effect of verbal instruction (P = 0.049) at L4-5.Post hoc analysis showed a greater increase with verbal instruction #3 than verbal instruction #2 (P = 0.009). There was no significant main effect of group at either segment.Discussion: The results of the study suggest that both groups responded similarly to the three verbal instructions. Verbal instructions may increase lumbar multifidus muscle thickness by different amounts at L4-5, but by the same amount at L5-S1.

Effects of Low-Load Motor Control Exercises and a High-Load Lifting Exercise on Lumbar Multifidus Thickness: A Randomized Controlled Trial.

Randomized controlled trial. The aim of this study was to compare the effects of low-load motor control (LMC) exercises and a high-load lifting (HLL) exercise, on lumbar multifidus (LM) thickness on either side of the spine and whether the effects were affected by pain intensity or change in pain intensity. There is evidence that patients with low back pain (LBP) may have a decreased size of the LM muscles with an asymmetry between sides in the lower back. It has also been shown that LMC training can affect this asymmetry. It is, however, not known whether a high-load exercise has the same effect. Sixty-five participants diagnosed with nociceptive mechanical LBP were included and randomized into LMC exercises or a HLL exercise, the deadlift. The LM thickness was measured using rehabilitative ultrasound imaging (RUSI), at baseline and after a 2-month training period. There were no differences between interventions regarding effect on LM muscle thickness. However, the analysis showed a significant effect for asymmetry. The thickness of the LM muscle on the small side increased significantly compared with the large side in both intervention groups, without influence of pain at baseline, or change in pain intensity. At baseline, there was a difference in thickness of the LM muscles between sides. It seems that exercises focusing on spinal alignment may increase the thickness of the LM muscles on the small side, irrespective of exercise load. The increase in LM thickness does not appear to be mediated by either current pain intensity or the magnitude of change in pain intensity. 2.

Association of sagittal spinal alignment with thickness and echo intensity of lumbar back muscles in middle-aged and elderly women

ObjectiveQuantitative changes, such as a decrease in muscle mass, and qualitative changes, such as an increase in the amount of intramuscular non-contractile tissue, occur with aging. However, it is unclear whether quantitative or qualitative changes in back muscles are associated with spinal alignment in the standing position. We investigated the association of sagittal spinal alignment with muscle thickness as an index of the mass of lumbar back muscles and muscle echo intensity as an index of the amount of non-contractile tissue within these muscles. MethodsStudy participants comprised 36 middle-aged and elderly women. Thickness and echo intensity of erector spinae, psoas major, and lumbar multifidus muscles were measured using an ultrasound imaging device. Standing sagittal spinal alignment, determined from thoracic kyphosis and lumbar lordosis angles, and the sacral anterior inclination angle was measured using the Spinal Mouse. ResultsStepwise regression analysis performed using muscle thickness, echo intensity, and age as independent variables showed that erector spinae muscle thickness was a significant determinant of the thoracic kyphosis angle. Psoas major muscle thickness and echo intensity of the lumbar multifidus muscle were significant determinants of the sacral anterior inclination angle. ConclusionOur results suggest that an increase in thoracic kyphosis is associated with a decrease in the mass of the erector spinae muscle, and that a decrease in pelvic anterior inclination is associated with a decrease in the mass of the psoas major muscle and an increase in the amount of non-contractile tissue within the lumbar multifidus muscle.

Reliability of diagnostic ultrasound in measuring the multifidus muscle.

BackgroundUltrasound is frequently used to measure activity in the lumbar multifidus muscle (LMM). However previous reliability studies on diagnostic ultrasound and LMM have included a limited number of subjects and few have used Bland-Altman’s Limits of Agreement (LOA). Further one does not know if activity affects the subjects’ ability to contract the LMM.MethodsFrom January 2012 to December 2012 an inter- and intra-examiner reliability study was carried out in a clinical setting. It consisted of a total of four experiments with 30 subjects in each study. Two experienced examiners performed all measurements. Ultrasound measurements were made of: 1. the LMM in the resting state, 2. during a contracted state, 3. on subsequent days, and, before and after walking. Reliability and agreement was tested for 1. resting LMM, 2. contracted LMM, and 3. thickness change in the LMM. Mean values of three measurements were used for statistical analysis for each spinal level. The intra-class correlation coefficient (ICC) 3.1 and 3.2 was used to test for reliability, and Bland-Altman’s LOA method to test for agreement.ResultsAll of the studies indicate high levels of reliability, but as the LMM thickness increased (increasing contraction) the agreement between examiners was poorer than for low levels of contraction.ConclusionsThe use of diagnostic ultrasound to measure the LMM seems to be reliable in subjects who have little or no change in thickness of the LMM with contraction.

A Fully Automatic Measurement of Lumbar Multifidus Muscle Thickness from Ultrasound Image

A Fully Automatic Measurement of Lumbar Multifidus Muscle Thickness from Ultrasound Image