Morphological changes of the lateral abdominal muscles in adolescent soccer players with low back pain: A prospective cohort study

Effect of a Ten-week Sensorimotor Exercise Program on the Side-to-Side LAM Asymmetry of Adolescent Football Players: A Randomized Control Trial

In this study we, evaluated the effects of a 10-week sensorimotor exercise program on the thickness and side-to-side asymmetry of the lateral abdominal muscles in adolescent soccer players. From among 120 initially recruited participants, we included 90 athletes (aged 10-17 years old) in our final analysis. Healthy athletes who met our inclusion criteria were randomly divided into comparative experimental and control groups. Sensorimotor exercises were conducted twice weekly for 10-weeks in the experimental group, and the control group received no intervention. We took ultrasound measurements when participants were in supine and standing rest positions. In the supine position, the experimental group (a) reduced the asymmetry of the internal oblique (IO) muscle by 0.4 mm (MD: 0.7; 95% CI 0.6-1.1); (b) increased the thickness of the external oblique (EO) muscle on the right by 0.7 mm (MD: 0.2; 95% CI 0.1-0.6) and on the left by 0.9 mm (MD: 0.2, 95% CI 0.2-0.7); and (c) increased the muscle on the IO right by 0.8 mm (MD: 0.3; 95% CI 0.2-0.9) and on the, left by 1.2 mm (MD: 0.4 95% CI 0.3-1.1). In a standing position the experimental group increased the thickness of the EO on the right by 1.5 mm (MD: 0.6; 95% CI 0.03-1.2) and on the left by 2.1 mm (MD: 0.6; 95% CI 0.1-1.3) and increased the IO on the right by 1.2 mm (MD: 0.7; 95% CI 0.2-1.7) and on the left by 1.1 mm (MD: 0.9; 95%CI 0.1-2.0). Thus, this 10-week program of additional sensorimotor exercises reduced the (side-to-side) asymmetry of the internal oblique muscle and increased the thickness of the EO and IO muscles in young football players.

Effect of strengthening and weakening of abdominal and dorsal muscles on lumbar spine loads in parents of disabled children

Pain in the lower part of the back is one of the most common chronic illnesses globally. This work aimed to determine the impact of the reinforcement of particular groups of abdominal and dorsal muscles on the loads exerted on the lumbar section of the spine in 30 mothers of children with motor disabilities. An optical Ariel Performance Analysis System recorded and processed the kinematics data of everyday activities. Tests investigating the effects of the strengthening or weakening of abdominal and dorsal muscles on loading in the lumbar section of the spine utilized the AnyBody Modelling System. Input data for the simulations included mean values of body positions, while the effects of strengthening or weakening of muscles were simulated in the muscle forces model by introducing different values for muscle physiological cross-sectional area (PCSA). Simulations used decreasing or increasing PCSA values of abdominal muscles and the erector spinae. The analysis involved component and resultant force values on the lumbosacral joint (L5-S1) of the spine and intra-abdominal pressure values. The highest reduction of the resultant reaction value in L5-S1 was observed in the simulations that increased the PCSA of the transverse abdominal (TrA). Indeed, a double increase in the TrA cross-section caused a reduction of the resultant reaction in L5-S1 by 30% and the anterior-posterior and proximal-distal forces by approximately 20-30%. Increased PCSA of the erector spinae exerted higher loads on the spine. These results indicate that strengthening weakened abdominal muscles, particularly TrA, in parents of children with motor disabilities reduces lower spinal loads during daily activities.

Comparison of whole trunk muscle mass between healthy and lumbar herniated nucleus pulposus patients using abdominal pelvic computed tomography

Background

Paraspinal muscle asymmetry is associated with low back pain (LBP) problems. This study aimed to analyze skeletal muscle areas around the lumbar vertebra and compare the ratio of anterior and posterior muscles between patients with lumbar herniated nucleus pulposus (HNP) and healthy individuals using abdominal pelvic computed tomography (APCT).

Methods

After propensity score matching, 122 HNP patients and 122 non-HNP individuals were finally used for analyses. In APCT, axial cut images were collected at the level of the third lumbar vertebra lower end plate and only the muscle structure was obtained. After obtaining the muscular portion of their image, we measured the skeletal muscle area (SMA). Second, for analysis relation of sarcopenia and HNP, the status of low skeletal muscle mass was determined using a previously reported criteria based on APCT scans in the Republic of Korea.

Results

From the analysis of the anterior-posterior muscles, the ratio of anterior SMA was statistically significantly larger in the HNP group than in the non-HNP group. Regarding the anatomical classification of trunk muscles, a statistically significant left-right imbalance to peripheral muscle in HNP men was observed. Regarding the status of low skeletal muscle mass, no statistical difference in prevalence between the two groups were observed. Moreover, no statistical difference in the prevalence of low skeletal muscle mass obesity was observed.

Conclusion

The lumbar flexor muscle was larger in HNP than others, showing trunk muscle imbalance. However, low skeletal muscle mass is not associated with HNP.

Whole Body Vibration: A Valid Alternative Strategy to Exercise?

Several studies agree that mechanical vibration can induce physiological changes at different levels, improving neuromuscular function through postural control strategies, muscle tuning mechanisms and tonic vibration reflexes. Whole-body vibration has also been reported to increase bone mineral density and muscle mass and strength, as well as to relieve pain and modulate proprioceptive function in patients with osteoarthritis or lower back pain. Furthermore, vibratory training was found to be an effective strategy for improving the physical performance of healthy athletes in terms of muscle strength, agility, flexibility, and vertical jump height. Notably, several benefits have also been observed at the brain level, proving to be an important factor in protecting and/or preventing the development of age-related cognitive disorders. Although research in this field is still debated, certain molecular mechanisms responsible for the response to whole-body vibration also appear to be involved in physiological adaptations to exercise, suggesting the possibility of using it as an alternative or reinforcing strategy to canonical training. Understanding these mechanisms is crucial for the development of whole body vibration protocols appropriately designed based on individual needs to optimize these effects. Therefore, we performed a narrative review of the literature, consulting the bibliographic databases MEDLINE and Google Scholar, to i) summarize the most recent scientific evidence on the effects of whole-body vibration and the molecular mechanisms proposed so far to provide a useful state of the art and ii) assess the potential of whole-body vibration as a form of passive training in place of or in association with exercise.

The effect and mechanism of traditional Chinese exercise for chronic low back pain in middle-aged and elderly patients: A systematic review

Background

Increasing lines of evidence indicate that traditional Chinese exercise (TCE) has potential benefits in improving chronic low back pain (CLBP) symptoms. To assess the clinical efficacy of TCE in the treatment of CLBP, we performed a systematic review of existing randomized controlled trials (RCTs) of CLBP and summarized the neural mechanisms underlying TCE in the treatment of CLBP.

Methods

A systematic search was conducted in four electronic databases: PubMed, Embase, the Cochrane Library, and EBSCO from January 1991 to March 2022. The quality of all included RCTs was evaluated by the Physiotherapy Evidence Database Scale (PEDro). The primary outcomes included pain severity and pain-related disability.

Results

A total of 11 RCTs with 1,256 middle-aged and elderly patients with CLBP were included. The quality of all 11 included RCTs ranged from moderate to high according to PEDro. Results suggested that TCE could considerably reduce pain intensity in patients with CLBP. Overall, most studies did not find any difference in secondary outcomes (quality of life, depression, and sleep quality).

Conclusion

The neurophysiological mechanism of TCE for treating CLBP could be linked to meditation and breathing, posture control, strength and flexibility training, and regulation of pain-related brain networks. Our systematic review showed that TCE appears to be effective in alleviating pain in patients with CLBP.

Incidence, prevalence and risk factors for low back pain in adolescent athletes: a systematic review and meta-analysis

OBJECTIVE

To investigate the incidence, prevalence, risk factors and morphological presentations of low back pain (LBP) in adolescent athletes.

DESIGN

Systematic review with meta-analysis.

DATA SOURCES

Medline, Embase, CINAHL via EBSCO, Web of Science, Scopus.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Studies evaluating the incidence and/or prevalence of LBP in adolescent athletes across all sports.

RESULTS

There were 80 studies included. The pooled incidence estimate of LBP in adolescent athletes was 11% (95% CI 8% to 13%, I²=0%) for 2 years, 36.0% (95% CI 4% to 68%, I²=99.3%) for 12 months and 14% (95% CI 7% to 22%, I²=76%) for 6 months incidence estimates. The pooled prevalence estimate of LBP in adolescent athletes was 42% (95% CI 29% to 55%, I²=96.6%) for last 12 months, 46% (95% CI 41.0% to 52%, I²=56%) for last 3 months and 16% (95% CI 9% to 23%, I²=98.3%) for point prevalence. Potential risk factors were sport participation, sport volume/intensity, concurrent lower extremity pain, overweight/high body mass index, older adolescent age, female sex and family history of LBP. The most common morphology reported was spondylolysis. Methodological quality was deemed high in 73% of cross-sectional studies and in 30% of cohort studies. Common reasons for downgrading at quality assessment were use of non-validated survey instruments and imprecision or absence of LBP definition.

SUMMARY/CONCLUSION

LBP is common among adolescent athletes, although incidence and prevalence vary considerably due to differences in study methodology, definitions of LBP and data collection.

PROSPERO REGISTRATION NUMBER

CRD42020157206.

Automated ultrasound measurements of lateral abdominal muscles under controlled breathing phases

BACKGROUND AND OBJECTIVES

A breathing phase during ultrasound measurements of the lateral abdominal muscles (LAMs) are usually indirectly controlled by visual inspection of the position of the transversus abdominis (TrA) muscle. This is due to the lack of devices to directly control airflow that are connected to the ultrasound in order to automatically and simultaneously freeze ultrasound images at the programmed breathing phase. Such indirect control may be related with potential measurement error because LAMs are respiratory muscles. Thus, the aim of this study was to present a newly developed and automatic measurement procedure to directly control airflow and at the same time automatically collect ultrasound images at the programed breathing phase. Additionally, it was decided to compare LAMs measurements obtained manually by the examiner and with an external device controlling the peak phase of tidal inspiration and expiration and compare the elasticity and thickness measurements between tidal inspiration and expiration in young participants.

METHODS

The study was carried out on 10 healthy youth. The thickness and shear modulus were measured by an Aixplorer ultrasound scanner. The measurements were obtained manually by the examiner and with a newly developed external device controlling the peak phases of tidal inspiration and expiration.

RESULTS

A significant difference in external/internal oblique thickness between the expiration and inspiration phases depended on the measurement procedure. The TrA thickness was similar during inspiration and expiration. During inspiration, the TrA shear modulus was higher than during expiration, and the TrA shear modulus depended on the measurement procedure.

CONCLUSION

Although the raw LAMs thickness and external/internal oblique thickness/shear modulus data were similar, the measurement procedure may affect the interpretation of the results. The TrA shear modulus is the most vulnerable to errors related to the measurement procedure. Construction of this study device controlling airflow and automatically collecting ultrasound images at the selected breathing phase seems to be promising in future studies considering measurements of respiratory muscles in a strictly defined breathing phase.

The Effects of Whole-Body Vibration Exercise on Anticipatory Delay of Core Muscles in Patients with Nonspecific Low Back Pain

Objective

The objective of this study is to determine the effect of whole-body vibration (WBV) exercise on the anticipatory delay of core muscles in nonspecific low back pain (NSLBP) patients.

Methods

Forty participants with NSLBP were randomly divided into the WBV group and the control group. The sEMG signals of deltoid, erector spines (ES), multifidus (MF), rectus abdominis (RA), and transversus abdominus/internal oblique muscles (TrA/IO) were recorded before and after the intervention in the weight-shifting task. The relative activation time of each muscle was calculated.

Results

In the WBV group, the relative activation time of bilateral MF and bilateral TrA/IO was significantly reduced on shoulder flexion (right MF: P=0.014; left MF: P=0.011; right TrA/IO: P=0.008; left TrA/IO: P=0.026). As for shoulder abduction, except for the left TrA/IO and the left RA, the relative activation time of other muscles was significantly reduced (right ES: P=0.001; left ES: P < 0.001; right MF: P=0.001; left MF: P=0.009; right TrA/IO: P < 0.001; right RA: P=0.001). In the control group, there was no significant difference in the relative activation time of each muscle before and after the intervention (P > 0.05).

Conclusions

WBV exercise can effectively alleviate the anticipatory delay of core muscles in NSLBP patients, but the long-term effects still need further study. This trial is registered with ChiCTR-TRC-13003708.

Effect of Transversus abdominis muscle training on pressure-pain threshold in patients with chronic low Back pain

Background

Therapeutic training is the most commonly used treatment methods for chronic low back pain (CLBP), and the use of a pressure biofeedback unit for transversus abdominis muscle (TrA) training is one of the core muscle training methods. The study aim of this research is to explore the effects of different intensities (sham training, low-intensity and high-intensity) of TrA muscle training on people with CLBP in pressure-pain threshold (PPT).

Methods

A total of 45 patients with CLBP were recruited, of whom 44 were included in the analysis. Fifteen, 14, and 15 were included in the sham training group, the low-intensity group, and the high-intensity group, respectively. A pressure biofeedback unit was used in performing a one-time TrA training intervention involving 30 times of 180 mmHg TrA contraction training at high intensity for 10 min and 15 times of 100 mmHg TrA contraction training at low intensity for 5 min. The sham training group completed comfort exercises and did not undergo training. The evaluation indicators were as follows: PPT, short-form McGill pain questionnaire, and body surface pain radiation.

Results

High-intensity training could activate more waist core muscles than low-intensity training. Significant changes on PPT (units: kgf) were observed in the following four muscles immediately after high-intensity training: iliopsoas [0.69 (0.13–1.25) 95% CI, p = 0.020]; quadratus lumborum [0.84 (0.23–1.45) 95% CI, p = 0.012]; erector spinae [0.66 (0.18–1.15) 95% CI, p = 0.011]; transversus abdominis [0.70 (0.26–1.14) 95% CI, p = 0.004], and in three muscles after low-intensity training: quadratus lumborum [0.61 (0.17–1.05) 95% CI, p = 0.009]; transversus abdominis [0.14 (from − 0.15 to 0.43) 95% CI, p = 0.022]; piriformis [0.55 (0.13–0.98) 95% CI, p = 0.014]. The change in body surface pain radiation immediately after exercise was [− 10.87 (from − 17.51 to − 4.22) 95% CI, p = 0.003] for high-intensity training and [− 5.21 (from − 9.40 to − 1.03) 95% CI, p = 0.019] for low-intensity training.

Conclusions

TrA training could increase the PPT of the waist core muscles and reduce the radiation range of waist pain. The benefits of high-intensity training are higher than those of low-intensity training.

Trial registration

ChiCTR-TRC-13003701. Registered 18 October 2013.

Code of ethical approval: 2018069.

Shear wave elastography of the lateral abdominal muscles in C-shaped idiopathic scoliosis: a case-control study

Considering that knowledge about lateral abdominal muscles (LAM) in idiopathic scoliosis (IS) is still very limited, the aims of this study were: (a) to compare LAM thickness and elasticity between C-shaped IS and non-scoliotic population; and (b) to compare LAM thickness and elasticity between C-shaped thoracic, thoracolumbar, and lumbar IS. A total of 259 adolescents were included in the final analysis; among these, 108 were IS and 151 were non-IS. LAM thickness and elasticity were measured at rest and during isometric contraction by an Aixplorer ultrasound scanner. Out of all LAM, only OE thickness was higher on the convex body side compared to the concave side in lumbar and thoracolumbar scoliosis. It may be related with muscle’s atrophy/hypertrophy or other tissues displacement rather than different force generated by the muscle on both body sides, because an asymmetry in the elasticity of the LAM between the convex and concave side was not presented. The only TrA was stiffer in lumbar scoliosis compared to thoracolumbar and thoracic scoliosis. LAM elasticity was similar in IS and non-IS adolescents.

The Relationship Between Low Back Pain Incidence and Ultrasound Assessment of Trunk Muscles in Adult Soccer Players: A Cohort Study

Background: Few studies have demonstrated the connection between trunk muscle thickness and low back pain (LBP) in athletes. Objectives: This study aimed to define whether the thickness of the lateral abdominal muscles (LAM) and lumbar multifidus (LM) are related to LBP incidence in elite male soccer players. Methods: In this short-term cohort study, 42 elite male soccer players from professional soccer teams were followed for a season. The muscle thickness of LAM and the cross-sectional area (CSA) of the LM were assessed. The relation between the incidence of LBP and the aforementioned factors was evaluated after the cohort study. Results: Thirty-seven participants completed the study, and seven participants (18.91%) experienced LBP during the follow-up period. No significant relationship was detected between LBP and the thickness of LAM and CSA of LM (P > 0.05). None of the other variables had any relationship with LBP incidence (P > 0.05). Conclusions: The LAM thickness and CSA of LM during a resting position and drawing-in maneuver was found not to be directly related to LBP incidence in elite male soccer players in the short term. Assessing these muscles’ conditions in more functional positions could be considered for further research.

Performance in dynamic movement tasks and occurrence of low back pain in youth floorball and basketball players

BACKGROUND

Prospective studies investigating risk factors for low back pain (LBP) in youth athletes are limited. The aim of this prospective study was to investigate the association between hip-pelvic kinematics and vertical ground reaction force (vGRF) during landing tasks and LBP in youth floorball and basketball players.

METHODS

Three-hundred-and-eighty-three Finnish youth female and male floorball and basketball players (mean age 15.7 ± 1.8) participated and were followed up on for 3 years. At the beginning of every study year the players were tested with a single-leg vertical drop jump (SLVDJ) and a vertical drop jump (VDJ). Hip-pelvic kinematics, measured as femur-pelvic angle (FPA) during SLVDJ landing, and peak vGRF and side-to-side asymmetry of vGRF during VDJ landing were the investigated risk factors. Individual exposure time and LBP resulting in time-loss were recorded during the follow-up. Cox's proportional hazard models with mixed effects and time-varying risk factors were used for analysis.

RESULTS

We found an increase in the risk for LBP in players with decreased FPA during SLVDJ landing. There was a small increase in risk for LBP with a one-degree decrease in right leg FPA during SLVDJ landing (HR 1.09, 95% CI 1.02 to 1.17, per one-degree decrease of FPA). Our results showed no significant relationship between risk for LBP and left leg FPA (HR 1.04, 95% CI 0.97 to 1.11, per one-degree decrease of FPA), vGRF (HR 1.83, 95% CI 0.95 to 3.51) or vGRF side-to-side difference (HR 1.22, 95% CI 0.65 to 2.27) during landing tasks.

CONCLUSIONS

Our results suggest that there is an association between hip-pelvic kinematics and future LBP. However, we did not find an association between LBP and vGRF. In the future, the association between hip-pelvic kinematics and LBP occurrence should be investigated further with cohort and intervention studies to verify the results from this investigation.

LEVEL OF EVIDENCE

Prognosis, level 1b.

Influence of phase of respiratory cycle on ultrasound imaging of deep abdominal muscle thickness

BACKGROUND

It is difficult to evaluate the transversus abdominis (TrA) and internal oblique (IO) due to their dual role in both trunk control and breathing.

OBJECTIVES

To investigate whether TrA and IO thickness as measured by ultrasound differs across the respiratory cycle in upright standing.

DESIGN

Observational study.

METHODS

Thickness of TrA and IO was measured with ultrasound in 67 subjects in upright standing. Measures were performed 3 times and by 2 assessors, at the end of relaxed expiration, at the end of a full inspiration, and at the end of full expiration. Differences were assessed by ANOVA. Intra- and inter-rater reliability (of a single measure and the average of 3 measures) were assessed by intra-class correlation (ICC).

RESULTS

Thickness of the TrA and IO was higher at full expiration than at the end of relaxed expiration (p < 0.001), and in turn compared to at full inspiration (p < 0.001). Intra-rater reliability was excellent at all respiratory phases (ICC 0.76-0.87). Whereas inter-rater reliability for a single measure was only fair to good for TrA (ICC 0.52-0.71) and good to excellent for IO (ICC 0.61-0.78), the inter-rater reliability of the average was excellent at all respiratory phases (ICC 0.75-0.90).

CONCLUSIONS

Thickness of TrA and IO increases when lung volume decreases. The intra- and inter-rater reliability of an average measure were excellent at the end of relaxed expiration, full inspiration and full expiration. This provides new opportunities to evaluate the deep abdominal muscles, and their role in respiration, in a physiotherapeutic setting.