Rehabilitative Ultrasound Imaging Measures Research Articles

M-Mode Ultrasound Behavior of Rectus Femoris and Vastus Intermedius during Contraction with Anthropometric Correlations: Cross-Sectional Study

The quadriceps femoris muscle (QF) is of clinical importance since it has been correlated with pathologies at knee level, such as anterior cruciate ligament (ACL) injury, pain processes and complex clinical conditions. Among the variables that have been related to these clinical conditions are anthropometric measurements, architecture and muscular behavior of the QF. The aim of this study was to determine the relationship between the rectus femoris (RF) and vastus intermedius (VIM) muscles’ behavior measured by rehabilitative ultrasound imaging (RUSI) M-mode under maximal voluntary isometric contraction (MVIC) and anthropometric measurements. This was a cross-sectional, observational study. Sixty-two asymptomatic volunteers were included (20.42 ± 4.97 years, most women 59.7%). RUSI measurements were muscle contraction/rest thickness and contraction/relaxation velocity. Anthropometric measurements were, lower limb length, RF length, QF tendon length, distance between spines, proximal, middle and distal thigh perimeter. Statistically significant correlations (p < 0.05) were found between VIM thickness at rest and contraction with thigh perimetry, RF length and dominant lower limb length. For the RF, a correlation was found between the thickness at rest and the length of this muscle (p = 0.003). There is a correlation between anthropometric variables and muscular behavior measured by RUSI M-mode.

The relationship between clinical examination measures and ultrasound measures of fascia thickness surrounding trunk muscles or lumbar multifidus fatty infiltrations: An exploratory study.

Patients with chronic low back pain (CLBP) exhibit remodelling of the lumbar soft tissues such as muscle fatty infiltrations (MFI) and fibrosis of the lumbar multifidus (LuM) muscles, thickness changes of the thoracolumbar fascia (TLF) and perimuscular connective tissues (PMCT) surrounding the abdominal lateral wall muscles. Rehabilitative ultrasound imaging (RUSI) parameters such as thickness and echogenicity are sensitive to this remodelling. This experimental laboratory study aimed to explore whether these RUSI parameters (LuM echogenicity and fascia thicknesses), hereafter called dependent variables (DV) were linked to independent variables (IV) such as (1) other RUSI parameters (trunk muscle thickness and activation) and (2) physical and psychological measures. RUSI measures, as well as a clinical examination comprising physical tests and psychological questionnaires, were collected from 70 participants with LBP. The following RUSI dependent variables (RUSI-DV), measures of passive tissues were performed bilaterally: (1) LuM echogenicity (MFI/fibrosis) at three vertebral levels (L3/L4, L4/L5 and L5/S1); (2) TLF posterior layer thickness, and (3) PMCT thickness of the fasciae between subcutaneous tissue thickness (STT) and external oblique (PMCTSTT/EO ), between external and internal oblique (PMCTEO/IO ), between IO and transversus abdominis (PMCTIO/TrA ) and between TrA and intra-abdominal content (PMCTTrA/IA ). RUSI measures of trunk muscle's function (thickness and activation), also called measures of active muscle tissues, were considered as independent variables (RUSI-IV), along with physical tests related to lumbar stability (n=6), motor control deficits (n=7), trunk muscle endurance (n=4), physical performance (n=4), lumbar posture (n=2), and range of motion (ROM) tests (n=6). Psychosocial measures included pain catastrophizing, fear-avoidance beliefs, psychological distress, illness perceptions and concepts related to adherence to a home-based exercise programme (physical activity level, self-efficacy, social support, outcome expectations). Six multivariate regression models (forward stepwise selection) were generated, using RUSI-DV measures as dependent variables and RUSI-IV/physical/psychosocial measures as independent variables (predictors). The six multivariate models included three to five predictors, explaining 63% of total LuM echogenicity variance, between 41% and 46% of trunk superficial fasciae variance (TLF, PMCTSTT/EO ) and between 28% and 37% of deeper abdominal wall fasciae variance (PMCTEO/IO , PMCTIO/TrA and PMCTTrA/IA ). These variables were from RUSI-IV (LuM thickness at rest, activation of IO and TrA), body composition (percent fat) and clinical physical examination (lumbar and pelvis flexion ROM, aberrant movements, passive and active straight-leg raise, loaded-reach test) from the biological domain, as well as from the lifestyle (physical activity level during sports), psychological (psychological distress-cognitive subscale, fear-avoidance beliefs during physical activities, self-efficacy to exercise) and social (family support to exercise) domains. Biological, psychological, social and lifestyle factors each accounted for substantial variance in RUSI-passive parameters. These findings are in keeping with a conceptual link between tissue remodelling and factors such as local and systemic inflammation. Possible explanations are discussed, in keeping with the hypothesis-generating nature of this study (exploratory). However, to impact clinical practice, further research is needed to determine if the most plausible predictors of trunk fasciae thickness and LuM fatty infiltrations have an effect on these parameters.

Concurrent Validity and Reliability of Manual Versus Specific Device Transcostal Measurements for Breathing Diaphragm Thickness by Ultrasonography in Lumbopelvic Pain Athletes.

The use of rehabilitative ultrasound imaging (RUSI) to evaluate diaphragm thickness during breathing in athletes who suffer from non-specific lumbopelvic pain presents some measurement errors. The purpose of this study was to evaluate intra- and inter-sessions, intra- and inter-rater reliabilities, and concurrent validity of diaphragm thickness measurements during breathing using transcostal RUSI with a novel thoracic orthotic device that was used to fix the US probe versus those measurements obtained using manual fixation. A total of 37 athletes with non-specific lumbopelvic pain were recruited. Intra- (same examiner) and inter-rater (two examiners) and intra- (same day) and inter-session (alternate days) reliabilities were analyzed. All measurements were obtained after manual probe fixation and after positioning the thoracic orthotic device to fix the US probe in order to correctly correlate both measurement methods. Both left and right hemi-diaphragm thickness measurements were performed by transcostal RUSI at maximum inspiration, expiration, and the difference between the two parameters during relaxed breathing. Intra-class correlation coefficients (ICC), standard errors of measurement (SEM), minimum detectable changes (MCD), systematic errors, and correlations (r) were assessed. Orthotic device probe fixation showed excellent reliability (ICC = 0.852–0.996, SEM = 0.0002–0.054, and MDC = 0.002–0.072), and most measurements did not show significant systematic errors (p > 0.05). Despite manual probe fixation with a reliability ranging from good to excellent (ICC = 0.714–0.997, SEM = 0.003–0.023, and MDC = 0.008–0.064 cm), several significant systematic measurement errors (p < 0.05) were found. Most significant correlations between both orthotic device and manual probe fixation methods were moderate (r = 0.486–0.718; p < 0.05). Bland–Altman plots indicated adequate agreement between both measurement methods according to the agreement limits. The proposed novel thoracic orthotic device may allow ultrasound probe fixation to provide valid and reliable transcostal RUSI measurements of diaphragmatic thickness during relaxed breathing thus reducing some measurement errors and avoiding systematic measurement errors. It may be advisable to measure diaphragm thickness and facilitate visual biofeedback with respect to diaphragm re-education during normal breathing in athletes with non-specific lumbopelvic pain.

Structural remodeling of the lumbar multifidus, thoracolumbar fascia and lateral abdominal wall perimuscular connective tissues: Medium-term test-retest reliability of ultrasound measures

IntroductionGrowing interest is being paid to the lumbar multifidus (LM) intramuscular fatty infiltrations and fibrosis that are secondary to low back pain as well to the remodeling of perimuscular connective tissues (fasciae) such as the thoracolumbar fascia and fascia sheets separating the abdominal wall muscles. Magnetic resonance imaging and computed tomography have traditionally been used but rehabilitative ultrasound imaging (RUSI) is much more affordable and practical, which can accelerate research and clinical applications on this topic. The aim of this study was to test the medium-term (8 weeks) test-retest reliability of the corresponding RUSI measures. MethodsThirty-four participants with non-acute LBP and 30 healthy controls performed a RUSI assessment before and after an 8-week time interval. LM echogenicity was quantified to assess fatty infiltrations and fibrosis while fasciae were quantified with thickness measures. Relative and absolute reliability were estimated using the generalizability theory as a framework, allowing to partition the different sources of error. ResultsOverall, the reliability findings were quite acceptable, with negligible systematic effects. Excellent relative reliability was reached in half of the investigated RUSI measures, particularly when averaging measures across trials. However, neither relative, nor absolute reliability results support the use of these RUSI measurements on an individual basis (e.g. clinical applications) but they are useful on a group basis (e.g. research applications). DiscussionThe different sources of error were distributed unequally across RUSI measures, pointing to different measurement strategies to mitigate the underlying errors. ConclusionsThe use of the generalizability theory allowed identifying the sources of error of the different RUSI measures. For each category of measure, depending of the distribution of errors, it was possible to recommend specific measurement strategies to mitigate them.

Structural remodeling of the lumbar multifidus, thoracolumbar fascia and lateral abdominal wall perimuscular connective tissues: A search for its potential determinants.

Recently remodeling of lumbar soft tissues has received increased research attention. However, the major determinants that influence remodeling need to be elucidated in order to understand the impact of different rehabilitation modalities on tissue remodeling. The main aim of this study was to explore the between-subject variance of different measures of lumbar soft tissues quantified with rehabilitative ultrasound imaging (RUSI). RUSI measures (n=8) were collected from 30 subjects without and 34 patients with LBP: (1) lumbar multifidus (LM) echogenicity (fatty infiltration/fibrosis) at three vertebral levels (L3/L4, L4/L5 and L5/S1) (n=3); (2) posterior layer thickness of the thoracolumbar fascia (n=1); and (3) thickness of the fasciae surrounding the external oblique (EO), internal oblique (IO), and transversus abdominis (TrA) (n=4). Forward stepwise multivariate regression modeling was conducted with these RUSI measures as dependent variables, using the following independent variables as potential determinants: age, sex, the presence of LBP, body size/composition characteristics (height, weight, trunk length, subcutaneous tissue thickness over the abdominal, and LM muscles), trunk muscle function (or activation) as determined with the percent thickness change of LM, EO, IO, and TrA muscles during a standardized effort (RUSI measures), and physical activity level during sport and leisure activities as estimated with a self-report questionnaire. Two or three statistically significant predictors (or determinants) were selected in the regression model of each RUSI measure (n=8 models), accounting for 26-64% of their total variance. The subcutaneous tissue thickness on the back accounted for 15-30% variance of LM echogenicity measures and thoracolumbar fascia thickness while the subcutaneous tissue thickness over the abdominals accounted for up to 42% variance of the fascia separating the subcutaneous adipose tissues and the EO muscle. The thickness of IO at rest accounted for 13-21% variance of all investigated abdominal fasciae except the fascia separating the subcutaneous adipose tissue and EO. Pain status accounted for 13-18% variance of the anterior and posterior fasciae of the TrA. Age accounted for 11-14% variance of LM echogenicity at all investigated vertebral levels while sex accounted for 15-21% variance of LM echogenicity at L3/L4 and fascia separating subcutaneous adipose tissue and EO muscle. The function (or activation) of EO and LM at L3/L4 accounted for 8-11% variance of the thoracolumbar fascia and fascia separating TrA and intra-abdominal content (TrA posterior fascia), respectively. Finally, the physical activity level during sport activities accounted for 7% variance of the fascia separating the subcutaneous adipose tissues and the EO muscle. These findings suggest that determinants other than body size characteristics may impact the remodeling of lumbar soft tissues, more importantly the subcutaneous adipose tissue deposits (thickness RUSI measures), which are associated with ectopic fat deposition in the LM and in the fasciae that are more closely positioned to the surface. While age, sex, and pain status explain some variability, modifiable factors such as physical activity level as well as trunk muscle thickness and function were involved. Overall, these results suggest that rehabilitation can potentially impact tissue remodeling, particularly in terms of intramuscular and perimuscular adipose tissues.

The Effects of Thrust Joint Manipulation on the Resting and Contraction Thickness of Transversus Abdominis in Patients With Low Back Pain: A Randomized Control Trial

ObjectiveTo investigate the immediate changes in resting and contracted thickness of the transversus abdominis (TrA) muscle after application of thrust joint manipulation (TJM) vs sham manipulation in participants with low back pain. MethodsA pretest–posttest randomized controlled trial design was performed. Consecutive subjects satisfying eligibility criteria completed patient-report outcome baseline measures, pretreatment rehabilitative ultrasound imaging (RUSI) measurements, followed by the randomly assigned intervention then, post-treatment RUSI measurements, and post-treatment & final patient-reported outcome measures. To compare the outcomes of TJM and sham manipulation on the TrA muscle thickness, a 2-by-2 analysis of variance (treatment [TJM and sham manipulation]) by time (pretreatment and post-treatment) was completed for both the TrA muscle thickness at rest and muscle thickness during contraction. Descriptive statistics including independent-sample t tests for continuous variables and χ2 tests for categorical variables were used to analyze differences in patient-reported outcome measures between groups. ResultsSixty-seven eligible participants agreed to participate. No significant interactions were identified for either muscle thickness at rest or contraction. ConclusionThis study did not support the hypothesis that manipulation would result in greater changes in TrA thickness at rest or during contraction in participants with low back pain. Based on prior research that identified subgroups of participants likely to respond to manipulation, future research should include participants more likely to respond favorably to TJM. This study was a priori registered with clinicaltrails.gov (NCT02558855).

Ultrasound Measures of the Abdominal Wall in Patients with Low Back Pain Before and After an 8-week Lumbar Stabilization Exercise Program, and Their Association With Clinical Outcomes.

Lumbar stabilization exercise programs (LSEPs) act positively on clinical outcome measures in patients with low back pain (LBP), but the underlying mechanisms are not well understood. Among the various neuromuscular mechanisms, a good candidate is better activation of the abdominal wall, as measured with rehabilitative ultrasound imaging (RUSI). To determine whether RUSI measures are (1) sensitive to LBP status and treatment (LSEP) and (2) correlate with clinical outcomes following the LSEP. An exploratory one-arm clinical trial with healthy participants as a control group. LSEP was delivered in a clinical setting; outcomes were measured in a laboratory setting. Thirty-one patients with nonacute LBP and 30 healthy controls. Outcome measures were performed before and after an 8-week LSEP in patients with LBP, and with the same time interval for control participants to compare with patients at baseline. Pain, disability, as well as static (at rest) and dynamic (percent thickness change) RUSI measures for abdominal muscles (transversus abdominis, internal oblique [IO], and external oblique [EO]). Patients did not produce systematic changes in RUSI measures relative to controls, even if patients had significant improvement in pain and disability. However, the correlational analyses between the absolute change (pre- to post-LSEP) (1) of EO and IO thickness (in mm) at rest (bilaterally), and (2) in pain following the LSEP were significant and consistent (range: .36-.45) in patients. Although positive clinical improvements were observed following LSEP, there were minimal systematic changes in RUSI measures, likely because patients were not different from controls at baseline. Correlational analyses, however, indicated that greater reductions in pain were associated with reduced thickness of the EO and IO following the LSEP, suggesting the presence of some heterogeneity (or clinical subgroups) among the patients. II.

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

Validity of measuring distal vastus medialis muscle using rehabilitative ultrasound imaging versus magnetic resonance imaging

Objective quantification of muscle size can aid clinical assessment when treating musculoskeletal conditions. To date the gold standard of measuring muscle morphology is magnetic resonance imaging (MRI). However, there's a growing body of evidence validating rehabilitative ultrasound imaging (RUSI) against MRI. ObjectiveThis study aimed to validate RUSI against MRI for the linear measurements of the distal fibres of vastus medialis muscle in the thigh.Twelve healthy male participants were recruited from a local university population. The distal portion of their right vastus medialis was imaged with the participant in long-sitting, using MRI and RUSI whilst the leg was in extension and neutral hip rotation. Cross sectional area (CSA) and three linear measures were taken from the MRI and these were compared with the same linear measures from RUSI. Statistical analysis included comparison of MRI and RUSI measures using the paired t-test and intra-class correlation coefficients (ICC 3,1).Mean differences between the linear measures taken from the MRI and RUSI were −0.5 mm to 2.9 mm (95% confidence intervals −0.6–8.3 mm), which were not statistically different (p > 0.05) and were highly correlated (ICCs 3,1 0.84–0.94). Correlations between the three linear measurements and muscle CSA ranged from r = 0.23 to 0.87, the greatest being muscle thickness. Multiplying the linear measures did not improve the correlation of 0.87 found for muscle thickness.Linear measures of vastus medialis depth made using RUSI were shown to be as valid as using MRI. Muscle thickness measures using RUSI could be used within an objective assessment of this muscle.

Intrasession and interrater reliability of rehabilitative ultrasound imaging measures of the deep neck flexors: A pilot study

The purpose of this investigation was to examine the intrasession and interrater reliability of rehabilitative ultrasound imaging (RUSI) to measure the deep neck flexors (DNF). Two investigators traced the DNF muscle borders in eight female subjects aged 33 ± 11.2 years. Of the eight subjects, five subjects reported a greater than 6-month history of neck pain, and three subjects were asymptomatic healthy controls. Cross-sectional area (CSA) (cm2) of right and left muscle groups were calculated. The intraclass correlation coefficients (ICC) for CSA measures were 0.67 (95% CI: 0.27–0.87) for rater 1 with a standard error of measurement (SEM) of 0.06 cm2; 0.87 (95% CI: 0.65–0.96) for rater 2 with an SEM of 0.09 cm2; and 0.68 (95% CI: 0.44–0.87) for interrater reliability between rater 1 and rater 2 with an SEM of 0.11 cm2. The mean difference between CSA (cm2) measures were 0.00 ± 0.10 cm2 for rater 1 and 0.09 ± 0.13 cm2 for rater 2. The mean differences for CSA were 0.04 ± 0.12 cm2. This pilot investigation suggests that RUSI could be used to reliably assess the size of the deep neck flexors.

A Systematic Review of the Reliability of Rehabilitative Ultrasound Imaging for the Quantitative Assessment of the Abdominal and Lumbar Trunk Muscles

Systematic review. To systematically review the literature on the rater reliability of Rehabilitative Ultrasound Imaging (RUSI) measurements to assess the morphology of the abdominal and lumbar trunk musculature. RUSI is an increasingly popular method of evaluating the morphology and function of muscles with real-time ultrasound. Conclusions regarding the reliability of measurements obtained by RUSI, need to be established before recommending its wider use. A systematic approach to searching and identifying original research articles reporting quantitative RUSI measurements was undertaken. Reliability data were extracted and methodologic quality was evaluated by 2 independent reviewers. Of the 24 studies included, 6 were deemed to be of high methodologic quality. Among high quality studies, some reported the measurement error associated with performing repeated measurements of the same image (intraimage analysis), whereas others reported the reliability of obtaining and measuring unique RUSI images (interimage analysis). Intraimage measurements demonstrated good intrarater and interrater reliability (ICC: >0.93). Interimage measurements demonstrated good reliability between raters (ICC: >0.90). Interimage, intrarater correlation coefficients were more variable with ICC values ranging from 0.62 to 0.97. The methodologic quality of research investigating the reliability of RUSI to measure the abdominal and lumbar trunk muscles needs to be improved. The majority of results of high quality studies indicate that RUSI has good levels of rater reliability. Improved reliability was observed among studies examining muscle thickness, and when using mean measurement values obtained by more experienced examiners.

The validity of Rehabilitative Ultrasound Imaging for measurement of trapezius muscle thickness

The purpose of the study was to establish the validity of Rehabilitative Ultrasound Imaging (RUSI) against Magnetic Resonance Imaging (MRI) for measuring trapezius muscle thickness. Participants were asymptomatic subjects recruited from Trinity College Dublin and associated teaching hospitals. Four MRI axial slices were made through each of the C6, T1, T5 and T8 spinous processes, with the subject supine. RUSI was performed immediately after MRI at the same vertebral levels, with the subject prone. Linear measurements of trapezius muscle thickness were made off-line on both the MRI and Ultrasound scans, in three regions: lower, middle and upper trapezius. Bland and Altman limits of agreement and Pearson's correlation coefficient were used to analyse the relationship between thickness measures taken from MRI and RUSI. Eighteen subjects (9 women) participated, (age-range 21–42 years). Results demonstrated good agreement between MRI and RUSI measurements of the lower trapezius muscle at T8 ( r = 0.77) and moderate agreement at T5, ( r = 0.62). Results were poor for the middle (T1) and upper (C6) trapezius muscles, ( r = −0.22 to 0.52) but may be explained by differences in both positioning and imaging planes between the 2 modalities. It was concluded that RUSI is a valid method of measuring lower trapezius muscle thickness.

Rehabilitative ultrasound measurement of select trunk muscle activation during induced pain

Rehabilitative ultrasound imaging (RUSI) is considered a valid method to measure muscle activation in key spinal muscles in asymptomatic subjects. Research measuring muscle activation with RUSI in painful subjects is limited. The aim of this study was to determine if changes in muscle activation from experimentally induced pain can be measured by RUSI. Six male subjects performed tasks known to activate the transverse abdominis (TrA) and lumbar multifidus (LM) while RUSI measurements of muscle thickness were obtained during control and hypertonic saline conditions. The abdominal draw-in maneuver was used to volitionally activate the TrA and a series of upper extremity lifting tasks were used to automatically activate the LM. Pain was induced by injecting 5% hypertonic saline into the longissimus muscle adjacent to the LM at the L4 level. The percent change in muscle thickness from rest to contraction represented muscle activation. Activation was significantly less ( p<0.01) during the painful condition on 4 of the 5 tasks performed for the LM and on the task performed for the TrA. These results indicate that RUSI can be used to measure pain-related changes in deep trunk muscle activation. Future research should include a larger sample size and women.