Measurement of transversus abdominis activation in chronic low back pain patients using a novel standardized real-time ultrasound imaging method

Effectiveness of an exercise intervention based on preactivation of the abdominal transverse muscle in patients with chronic nonspecific low back pain in primary care: a randomized control trial

BACKGROUND

Low back pain is one of the most common disabling pathologies in humanity worldwide. Physical exercises have been used in recent decades to reduce the pain, improve the functionality of the lumbar spine and avoid relapses. The purpose of the study is to analyze the effect of a program based on re-education exercises involving preactivation of the abdominal transverse muscle compared to conventional treatment in adults with chronic nonspecific low back pain.

METHODS

A two-arm, single-blind randomized control trial with 35 primary care patients with chronic nonspecific low back pain. Both groups received a 4-week intervention. Data were collected at baseline and at the end of the intervention. Sixteen patients participated in the intervention group, and 19 patients in the control group.

RESULTS

For the experimental group, the outcomes of disability and activation of the abdominal transverse muscle decreased significantly (MD -2.9; CI 95% -5.6 to -0.35; η2 = 0.14; p = 0.028) and (MD 2.3; CI 95% 0.91 to 3.67; η2 = 0.25; p = 0.002) respectively, with a large effect size, compared to the control group. There were no differences between the groups in pain intensity, thickness, and resistance of the transverse abdominal muscle.

CONCLUSION

A 4-week specific program based on re-education exercises of the preactivation of the abdominal transverse muscle is more effective than conventional treatment for reducing disability and increasing the activation of the abdominal transverse muscle measured by VAS scale and PBU.

TRIAL REGISTRATION

Clinicaltrials.gov identifier: NCT03097497. Date of registration: 31/03/2017.

MSK Ultrasound - An IJSPT Perspective

MSK ultrasound is a valuable imaging technique which has become increasingly popular in recent years. This efficient technique proves beneficial in a variety of ways. MSK ultrasound effectively streamlines the process by enabling practitioners to securely and accurately image and assess structures all in one simple step. By allowing healthcare providers to access critical information quickly and conveniently, MSK ultrasound can help identify conditions early when interventions are most effective. Moreover, it may be able to shorten diagnostic times and reduce costs through more cost-effective use of resources such as imaging and laboratory testing. Furthermore, MSK ultrasound can provide additional insights into musculoskeletal anatomy and help improve patient care and outcomes. In addition, utilizing this method reduces exposure to radiation and provides enhanced patient comfort with its quick scan duration. MSK ultrasound has a high potential to provide quick and accurate diagnosis of MSK disturbances when used correctly. As clinicians become more comfortable and familiar with this technology, we will continue to see its use expand for various MSK assessments. In this commentary we'll explore how ultrasound can be used in physical therapy, specifically for musculoskeletal assessment. We'll also look at some of the potential benefits and limitations of using ultrasound in PT practice.

Are There Differences in Abdominal Muscle Function in Female Singers With and Without Voice Disorders? - An Observational Study

OBJECTIVES

The purpose of this study was to determine the motor function of the abdominal muscles in singers with and without functional voice disorders and to examine them for possible differences. Additionally, the breathing behaviour and posture control was investigated.

STUDY DESIGN

Observational study.

METHODS

Female subjects (n = 20) with differing levels of professional competence were used to provide the data for analysis. By using the Singing Voice Handicap Index (SVHI) the grade of dysphonia could be measured, and the subjects were organized in groups. The change of muscle thickness of the M. transversus abdominis (TVA) and the M. obliquus internus abdominis (OIA) during different singing tasks was measured by using ultrasound. The subjects were then asked to perform the Abdominal Hollowing Test (AHT) with the STABILIZER. Finally, the subjects were all filmed while singing. The videos recordings of the singing sessions were analysed by an independent clinical expert regarding breathing and secondary motor activities (SMA). For the statistical analysis, the Mann-Whitney-U Test and the Chi-Square-Test was mainly used.

RESULTS

The results showed a significantly thinner TVA in the group with dysphonia in comparison to the group without dysphonia. Ultrasound measurements showed significantly higher changes of muscle thickness of the TVA during singing tasks in the group with dysphonia. Regarding the AHT there was a significant difference between the two groups. The group with dysphonia was not able to increase the pressure by 15mmHg. Furthermore, the healthy subjects demonstrated abdominal breathing, while the group with dysphonia present with thoracic breathing. Additionally, it was noted that the subjects with dysphonia showed a higher level of associated movements especially at and/or on the lumbar spine, cervical spine and the left arm and shoulder.

CONCLUSION

Differences in TVA-recruitment, breathing behaviour and secondary motor activities while singing were found. This study sparks new ideas for neuromusculoskeletal assessments and therapy.

Intra-rater reliability of transversus abdominis measurement by a novice examiner: Comparison of "freehand" to "probe force device" method of real-time ultrasound imaging

A "free hand" real-time-ultrasound method is commonly applied to measure transversus abdominis. Potentially, this increases transversus abdominis measurement error due to uncontrolled variability in probe to skin force, inclination, and roll, particularly for novice examiners. This single-group repeated-measures reliability study compared the intra-rater reliability of transversus abdominis thickness and activation measurement by a novice examiner between free hand and a standardized probe force device method. The examiner captured ultrasound videos of transversus abdominis in a single session in healthy participants (n =  33). Free hand ultrasound featured uncontrolled probe force, inclination, and roll, while probe force device method ultrasound standardized these parameters. Images of transversus abdominis at rest and contracted were measured and transversus abdominis activation calculated. Intraclass correlation coefficient, coefficient of variation, standard error of measurement, and worthwhile differences were calculated. The probe force device method resulted in greater reliability (intraclass correlation coefficient = 0.75-0.96) and lower measurement error (coefficient of variation = 8.89-28.7%) compared to free hand (intraclass correlation coefficient = 0.63-0.93; coefficient of variation = 6.52-29.4%). Reliability was good for all measurements except free hand TrA-C, which was moderate. TrA-C had the lowest reliability, followed by contracted thickness of the transverse abdominis, with resting thickness of the transverse abdominis being highest. Worthwhile differences were lower using a probe force device method versus free hand for resting thickness of the transverse abdominis and contracted thickness of the transverse abdominis and similar for TrA-C. Standardization using probe force device method ultrasound to measure transversus abdominis improved intra-rater reliability in a novice examiner. Use of a probe force device method is recommended to improve reliability through reduced sources of measurement error. Probe force device method intra- and inter-rater reliability in examiners of varying experience, in clinical populations, and to visualize other structures merits exploration.