Lateral abdominal muscle size at rest and during abdominal drawing-in manoeuvre in healthy adolescents

Reliability of Ultrasound Measurements of the Lumbar Multifidus and Transversus Abdominis Muscles during Lying and Unstable Sitting Positions in Individuals With and Without Chronic Low Back Pain

Background

The reliability studies are limited to support ultrasound usage during dynamic conditions; for example, unstable sitting position.

Objective

This study aims to examine the reliability of ultrasound measurements of the lumbar multifidus and transversus abdominis during lying and unstable sitting positions in individuals with chronic low back pain (CLBP) and asymptomatic individuals considering abnormal lumbar lordosis.

Material and Methods

In this observational study, intrarater within-day and between-day reliability of muscle thickness and contraction ratio of the lumbar multifidus and transversus abdominis muscles were assessed using ultrasound imaging. In total, 40 participants (27 with CLBP, 13 asymptomatic individuals) with abnormal lumbar lordosis were recruited. The degree of lumbar lordosis has been measured by a flexible ruler. The muscle thickness was assessed at lying and sitting on a gym ball for both muscles in three sessions.

Results

Both groups had well to high ICCs of thickness measurement and contraction ratio in the transversus abdominis and lumbar multifidus muscles during both static (ICC=0.71-0.99) and semi-dynamic conditions (ICC=0.73-0.98). The standard error of measurements and minimal detectable changes were rather small in both groups.

Conclusion

Ultrasound imaging is a highly reliable method to assess muscle thicknesses and contraction ratio of the transversus abdominis and lumbar multifidus during different conditions, even in patients with CLBP and abnormal lumbar lordosis.

An Investigation of the Association between Transversus Abdominis Myofascial Structure and Activation with Age in Healthy Adults using Ultrasound Imaging

BACKGROUND

Because of their importance in core stability, training the deep abdominal muscles, fascial structures and particularly the transversus abdominis, is a key component of many sport and physical therapy programs. However, there are gaps in knowledge about age-related changes in the structure and activation capacity of these muscles.

HYPOTHESIS/PURPOSE

This study investigated the association between deep abdominal muscles and fascial structures and transversus abdominis activation with age in healthy adults.

STUDY DESIGN

A cross-sectional study.

METHODS

Eighty-six adults aged 18 to 77 participated in this study. An ultrasound image of their transversus abdominis, internal oblique, external oblique and associated fasciae was first captured at rest, then during a contraction of the transversus abdominis. Bivariate correlation analyses and hierarchical analyses were performed (significance level: p < 0.05).

RESULTS

The thickness of these three muscles decreases with age ( ρ = -0.66 for external oblique, -0.51 for internal oblique and -0.58 for transversus abdominis), whereas the thickness of their fasciae increases ( ρ = 0.39 for the fascia of external oblique, 0.54 for the fascia between internal oblique and external oblique, and 0.74 for the fascia between internal oblique and transversus abdominis). Transversus abdominis activation decreases with age (r =-0.44). Age accounts for 19.5% of the variance in transversus abdominis activation.

CONCLUSION

These results demonstrate that normal aging is associated with changes in deep abdominal myofascial structures and transversus abdominis activation. Assessment of these metrics can provide valuable baseline information for physical therapists involved in rehabilitation and strengthening programs targeting older individuals.

LEVEL OF EVIDENCE

Level 2.

How Do the Abdominal Muscles Change during Hypopressive Exercise?

Background and objective: Prior studies have reported an activation of abdominal muscles during hypopressive exercises in women with pelvic floor disfunction. However, no previous research analyzed the effects of hypopressive exercise on abdominal muscles in healthy populations to understand the normal biomechanics of this area. The aim of this study was to examine the thickness of abdominal muscles at rest and during hypopressive exercise in supine and standing positions with ultrasound imaging in healthy adults. Methods: A cross-sectional study was carried out in 99 healthy university students. The thickness of the abdominal muscles at rest and during hypopressive exercise was assessed with ultrasound imaging in supine and standing positions. Results: During hypopressive exercise, there was a significant increase in the muscle thickness of transversus abdominis (p < 0.001) and internal oblique (p < 0.001) in supine and standing positions. External oblique only increased its thickness significantly in the standing position (p < 0.001) and rectus abdominis did not change during the hypopressive exercise in any position (p > 0.05). In conclusion, hypopressive exercises seem to increase the thickness of the deepest and most stabilized muscles such as transversus abdominis and internal oblique. Conclusions: These findings should be considered for future interventions with hypopressive exercises in healthy subjects.

Reliability of Sonography Measures of the Lumbar Multifidus and Transversus Abdominis during Static and Dynamic Activities in Subjects with Non-Specific Chronic Low Back Pain

PURPOSE

The purpose of this study was to investigate the test-retest reliability of ultrasound (US) thickness measurements and the muscle contraction ratio (CR) of lumbar multifidus (LM) and transversus abdominis (TA) muscles in participants with and without nonspecific chronic low back pain (NCLBP).

METHODS

A total of 62 participants (37 with NCLBP, 25 without NCLBP) with participated in the study. The within-day and between-day reliability of US thickness measurements and CR in a lying (supine for TA and prone for LM) and sitting positions for both muscles (sitting on a gym ball with both feet on the ground or lifting one foot off the floor) were assessed. Reliability analysis was performed with intraclass correlations (ICCs) for these two static and dynamic positions.

RESULTS

Test-retest reliability was calculated to be good to high for the static position (ICC = 0.72-0.95) and the dynamic position (ICC = 0.74-0.94) sonographic measurements in both group of TA measurement. Test-retest reliability of LM measurements was good to high for the static position (ICC = 0.82-0.95) and the dynamic position (ICC = 0.85-0.97) sonographic measurements in both groups.

CONCLUSIONS

US imaging is a highly reliable method for the assessment of TA and LM thickness muscles in the dynamic position in participants with and without NCLBP. The CR measures may be adequately reliable in assessing the function of the TA and LM muscles in participants with NCLBP and healthy ones.

Role of Ultrasound in Low Back Pain: A Review

Low back pain is one of most common musculoskeletal disorders around the world. One major problem clinicians face is the lack of objective assessment modalities. Computed tomography and magnetic resonance imaging are commonly utilized but are unable to clearly distinguish patients with low back pain from healthy patients with respect to abnormalities. The reason may be the anisotropic nature of muscles, which is altered in function, and the scans provide only structural assessment. In view of this, ultrasound may be helpful in understanding the disease as it is performed in real-time and comprises different modes that measure thickness, blood flow and stiffness. By the use of ultrasound, patients with low back pain have been found to differ from healthy patients with respect to the thickness and stiffness of the transversus abdominis, thoracolumbar fascia and multifidus. The study results are currently still not conclusive, and further study is necessary to validate. Future work should focus on quantitative assessment of these tissues to provide textural, structural, hemodynamic and mechanical studies of low back pain. This review highlights the current understanding of how medical ultrasound has been used for diagnosis and study of low back pain and discusses potential new applications.

Somatic regional oxygen saturation as an early marker of intra-abdominal hypertension in critically ill children: a pilot study

Background/aim

Intraabdominal hypertension is a common clinical condition with high mortality and morbidity in pediatric intensive care units. The aim of this study was to test the feasibility of regional tissue oxygenation (rSO2) measurement using near-infrared spectroscopy and to assess the correlation between rSO2 and perfusion markers of intraabdominal hypertension in high-risk pediatric patients.

Materials and methods

In this prospective observational cohort study in a tertiary pediatric intensive care unit in Çukurova University Faculty of Medicine, a total of 31 patients who were admitted between May 2017 and May 2018 with a risk of intraabdominal hypertension were included. Mesenteric and renal rSO2 measurements were taken and correlations with other tissue perfusion markers including mean arterial pressure, pH, lactate, intraabdominal pressure, abdominal perfusion pressure, mixed venous oxygen saturation, vasoactive inotropic score were assessed. Intraabdominal pressure was measured as ≥10 mmHg in 15 patients (48.3%) and these patients were defined as the group with intraabdominal hypertension.

Results

In the group with intraabdominal hypertension, mixed venous oxygen saturation was lower (P = 0.024), vasoactive inotropic score was higher (P = 0.024) and the mean abdominal perfusion pressure value was lower (P = 0.014). In the ROC analysis, the mesenteric rSO2 measurement was the best parameter to predict intraabdominal hypertension with area under the curve of 0.812 (P = 0.003) 95% CI [0.652–0.973].

Conclusion

Monitoring of mesenteric rSO2 is feasible in patients at risk for intraabdominal hypertension. Moreover, both mesenteric regional oxygen and perfusion markers may be used to identify pediatric patients at risk for intraabdominal hypertension.

Reliability of the lateral abdominal muscle thickness measurements in idiopathic scoliosis patients

BACKGROUND

To date, the reliability of ultrasound imaging (US) measures of the abdominal muscle thickness in idiopathic scoliosis (IS) patients during early stages of adolescence has not been confirmed.

OBJECTIVE

To assess the intra-rater reliability of US measures of the thickness of the external oblique (EO), internal oblique (IO), and transversus abdominis (TrA) on convex and concave body sides in adolescents with IS.

DESIGN

One-way repeated-measures analysis of variance (ANOVA) and reliability study.

METHODS

Fifteen patients diagnosed IS were included between the ages of 9 and 14 years. Three repeated US measurements were recorded in the supine resting position over 2 sessions, 24 h apart.

RESULTS

By assessing the mean value from the first two measurements (ICC_3,2), the reliability was between .76 and .95 for all examined muscles on the convex and concave sides. The reliability for the mean values from three measurements (ICC_3,3) was between .81 and .96. The smallest detectable difference values for single measurements were twice as high on the convex side than on the concave side for all examined abdominal muscles.

CONCLUSION

US measurements of the thickness of the EO, IO, and TrA muscles in supine rest position in adolescent IS patients are reliable. In order to increase measurement reliability, and due to variability in reliability between concave and convex body side, we recommend using the mean of three consecutive measurements of the EO, IO, and TrA muscles for adolescents with IS.

Body Mass Normalization for Lateral Abdominal Muscle Thickness Measurements in Adolescent Athletes

OBJECTIVES

To determine the value of allometric parameters for ultrasound measurements of the oblique external (OE), oblique internal (OI), and transversus abdominis (TrA) muscles in adolescent athletes. The allometric parameter is the slope of the linear regression line between the log-transformed body mass and log-transformed muscle size measurement.

METHODS

The study included 114 male adolescent football players between the ages of 10 and 19 years. All individuals with no surgical procedures performed on the trunk area and who had played a sport for at least 2 years were included. A real-time B-mode ultrasound scanner with a linear array transducer was used to obtain images of the lateral abdominal muscles from both sides of the body. A stabilometric platform was used to assess the body mass value.

RESULTS

The correlations between body mass and the OE, OI, and TrA muscle thicknesses were r = 0.73, r = 0.79, and r = 0.64, respectively (in all cases, P < .0001). The allometric parameters were 0.77 for the OE, 0.67 for the OI, and 0.61 for the TrA. Using these parameters, no significant correlations were found between body mass and the allometric-scaled thickness of the lateral abdominal muscles.

CONCLUSIONS

Significant positive correlations exist between body mass and lateral abdominal muscle thickness in adolescent athletes. Therefore, it is reasonable to advise that the values of the allometric parameters for the OE, OI, and TrA muscles obtained in this study should be used, and the allometric-scaled thicknesses of those muscles should be analyzed in future research on adolescent athletes.

Side differences of the lateral abdominal wall in supine rest position in mild adolescent idiopathic thoracolumbar scoliosis

Objectives

This study aims to evaluate the thickness of the abdominal muscles on both sides in patients with mild adolescent idiopathic scoliosis (AIS) and to assess the absolute and relative thickness of oblique external (OE), oblique internal (OI), and transversus abdominis (TrA).

Patients and methods

A total of 84 participants underwent ultrasonographic examination of the abdominal muscles in the supine resting position. All participants were divided into two groups including AIS group (n=42) and control group (n=42). The absolute and relative thicknesses of OE, OI, and TrA were recorded.

Results

In the AIS group, the TrA on the left side was significantly thicker by 0.30 mm (95% CI 0.01-0.7) than the right side. For relative values, the percentage contribution to the structure of the lateral abdominal wall of the OE on the right and the TrA on the left was significantly higher by 3.2% (95% CI 0.9-5.5) and 3.1% (95% CI 1.1-5.0), respectively, in the AIS group.

Conclusion

Our study results show that, in the supine resting position, the muscles of the lateral abdominal wall are thinner in AIS patients. In addition, side-to-side differences in the percentage contribution of the OE and TrA to the structure of the lateral abdominal wall are seen in this patient population, although these differences are independent of the direction of the scoliosis.

Body Mass Normalization for Ultrasound Measurements of Adolescent Lateral Abdominal Muscle Thickness

OBJECTIVES

The purpose of this study was to determine the value of the allometric parameter for ultrasound measurements of the thickness of the oblique external (OE), internal (OI), and transversus abdominis (TrA) muscles in the adolescent population. The allometric parameter is the slope of the linear regression line between the log transformed body mass and log transformed muscle size measurement.

METHODS

The study included 321 adolescents between the ages of 10 and 17, consisting of 160 boys and 161 girls. The participants were recruited from local schools and attended regular school classes at normal grade levels. All individuals with no signs of scoliosis (screening with use of a scoliometer), and no surgical procedures performed on the trunk area were included. A real-time ultrasound B-scanner with a linear array transducer was used to obtain images of the lateral abdominal muscles from both sides of the body.

RESULTS

The correlation between body mass and the OE muscle was r = 0.69; the OI muscle r = 0.68; and the TrA muscle r = 0.53 (in all cases, P < .0001). The allometric parameter for the OE was 0.88296; the OI 0.718756; and the TrA 0.60986. Using these parameters, no significant correlations were found between body mass and the allometric-scaled thickness of the lateral abdominal muscles.

CONCLUSIONS

Significant positive correlations exist between body mass and lateral abdominal muscle thickness assessed by ultrasound imaging. Therefore, it is reasonable to advise that the values of the allometric parameters for OE, OI, and TrA obtained in this study should be used in other studies performed on adolescents.

The importance of body mass normalisation for ultrasound measurement of the transversus abdominis muscle: The effect of age, gender and sport practice

BACKGROUND

Some studies have not considered body mass as a confounder in TrA analysis, which may have led to improper interpretation of results.

OBJECTIVES

To assess the differences in the effect of age, gender and physical activity between normalised for body mass and actual values of the TrA as well as to establish the effect of age, gender and physical activity on normalised for body mass TrA thickness in adolescents.

DESIGN

The study was a cross-sectional study conducted at selected primary and secondary schools, and colleges in the Silesian region of Poland.

METHOD

A real-time ultrasound was used to obtain images of the TrA muscle. Body mass normalisation for TrA thickness was performed with allometric scaling and the following equation: Allometric-scaled TrA = TrA thickness/body mass^0.61.

RESULTS

Analysis has shown that boys have significantly thicker muscle by 0.27 mm (95% CI 0.04-0.50) than girls, and those who practise sports have thicker muscle by 0.30 mm (95% CI 0.06-0.52) than non-active individuals. For allometric-scaled TrA, there were no significant effects (p > 0.50). There was a significant correlation between participants age and the actual value of the TrA (r = 0.42, p < 0.05). The correlation between age and allometric-scaled TrA was insignificant and close to zero (r = -0.006, p = 0.93).

CONCLUSIONS

An analysis of TrA thickness without body mass normalisation can deliver improper interpretation of study results. Thus, it is recommended in future researches to analyse TrA thickness measurement after normalisation rather than actual values. In the adolescent population, there is no effect of gender, age and physical activity on allometric-scaled TrA thickness.

Assessment of the abdominal muscles at rest and during abdominal drawing-in manoeuvre in adolescent physically active girls: A case-control study

BACKGROUND

An impact of regular physical activity (RPA) on the abdominal muscles may be significant when comparing various symptomatic groups. However, there is lack comprehensive information in this field. The objective of this study was to assess the lateral abdominal wall at rest and during abdominal drawing-in manoeuvre in adolescent physically active girls in different body positions.

METHODS

One hundred and forty-four female students, 13-17 years of age, participated in the study. Participants were divided into 2 groups based on a physical activity (PA) statement. Measurements of the thickness of the abdominal muscles at rest and during abdominal drawing-in manoeuvre were made in the supine and standing positions by ultrasound imaging.

RESULTS

Compared to the control group, activities of the obliquus internus and transversus abdominis muscles were higher in the regular PA group by 8.9% (95%CI: 3.1-14.7) and 36% (95%CI: 19.1-47.5), respectively. In the RPA group, the transversus abdominis preferential activation ratio was greater by 0.03 (95%CI: 0.01-0.04), and the contraction ratio was greater by a mean value of 0.35 (95%CI: 0.18-0.46).

CONCLUSION

RPA does not have any effect on the resting thickness of the abdominal muscles in the supine and standing positions. Girls performing RPA have a greater ability to perform an independent activation and greater contractions of the transversus abdominis.

Comparison of Lateral Abdominal Muscle Thickness and Cross Sectional Area of Multifidus in Adolescent Soccer Players with and without Low Back Pain: A Case Control Study

BACKGROUND

Low back pain (LBP) is a common complaint amongst adolescent athletes. While different studies have shown association between LBP and trunk muscle thickness in the general population, few articles have studied it in adolescent athletes.

OBJECTIVES

The aim of this study is to compare lateral abdominal muscle thickness and function, and cross sectional area (CSA) of lumbar multifidus (LM) in adolescent soccer players with and without LBP.

METHODS

In total, 28 adolescent soccer players with and without LBP, from the premier league participated in this study. The thickness of external oblique, internal oblique and transversus abdominis and the CSA of the LM muscles at L4 level on both sides were measured at rest and contraction via ultrasound imaging (USI). In addition, leg length discrepancy, hamstring flexibility, active lumbar forward flexion, and isometric muscle endurance of trunk extensors were measured in both groups. (study design/setting: case control study).

RESULTS

The mean (SD) age in LBP group and non-LBP group were 14.0 (1.1) and 14.1 (0.9) years, respectively. There was no significant difference in baseline characteristics of participants between groups. Findings showed no significant difference between LBP and non-LBP groups comparing all measured variables.

CONCLUSIONS

The data obtained support that there is not a correlation between abdominal muscle thickness and CSA of the lumbar multifidi and LBP in adolescent soccer players. These findings suggest that other factors rather than the thickness of deep trunk muscles may play a more significant role in the etiology of LBP in adolescent soccer players.

Measurement of superficial and deep abdominal muscle thickness: an ultrasonography study

Background

Real-time ultrasound imaging is a valid method in the field of rehabilitation. The ultrasound imaging allows direct visualization for real-time study of the muscles as they contract over the time. Measuring of the size of each abdominal muscle in relation to the others provides useful information about the differences in structure, as well as data on trunk muscle activation patterns. The purpose of this study was to assess the size and symmetry of the abdominal muscles at rest in healthy adults and to provide a reference range of absolute abdominal muscle size in a relatively large population.

Method

A total 156 healthy subjects with the age range of 18–44 years were randomly recruited. The thickness of internal oblique, external oblique, transverse abdominis, and rectus abdominis muscles was measured at rest on both right and left sides using ultrasound. Independent t test was used to compare the mean thickness of each abdominal muscle between males and females. Differences on side-to-side thicknesses were assessed using paired t test. The association between abdominal muscle thicknesses with gender and anthropometric variables was examined using the Pearson correlation coefficient.

Results

A normal pattern of increasing order of mean abdominal muscle thickness was found in both genders at both right and left sides: transverse abdominis < external oblique < internal oblique < rectus abdominis. There was a significant difference on the size of transverse abdominis, internal oblique, and external oblique muscles between right and left sides in both genders. Males had significantly thicker abdominal muscles than females. Age was significantly correlated with the thickness of internal oblique, external oblique, and rectus abdominis muscles. Body mass index was also positively correlated with muscle thickness of rectus abdominis and external oblique.

Conclusions

The results provide a normal reference range for the abdominal muscles in healthy subjects and may be used as an index to find out abnormalities and also to evaluate the effectiveness of different interventions.