The Influence of Dual Pressure Biofeedback Units on Pelvic Rotation and Abdominal Muscle Activity during the Active Straight Leg Raise in Women with Chronic Lower Back Pain

Repeatability and reproducibility of the pressure biofeedback unit

INTRODUCTION

Although the pressure biofeedback unit (PBU) is used for muscular assessment and training, there is little evidence of its reproducibility and repeatability.

OBJECTIVE

This study aims to assess intra- and inter-rater reproducibility and repeatability of the PBU in the assessment of the transverse abdominal (TrA), internal oblique (IO), low back multifidi, and deep neck flexors (DNF).

METHODS

Fifty individuals had three muscular groups tested: TrA/IO, lower back multifidi, and DNF. For repeatability, one rater did three consecutive measures; for intra-rater reproducibility the same rater did two measures with seven-day intervals, and for inter-rater reproducibility, three raters, on the same day, did the measures. Data were analyzed with: Intraclass Correlation Coefficient (ICC), Standard Error of Measurement (SEM), and Minimal Detectable Change (MDC). (α = 0,05).

RESULTS

Repeatability: TrA/IO (ICC = 0.847), Multifidi (ICC = 0.860), DNF (ICC = 0.831). Inter-rater reproducibility: TrA/IO (ICC = 0.876), Multifidi (ICC = 0.508), DNF (ICC = 0.442). Intra-rater reproducibility: TrA/IO (ICC = 0.747), Multifidi (ICC = 0.293), DNF (ICC = 0.685). Except for Multifidi, all the SEM values were less than 10 mmHg and the MDC values were less than 15 mmHg.

CONCLUSIONS

The PBU can be used with reliability by different evaluators, although the evaluation of multifidi is not indicated.

Feasibility of the Archercise biofeedback device to strengthen foot musculature

Background

Foot muscle weakness can produce foot deformity, pain and disability. Toe flexor and foot arch exercises focused on intrinsic foot muscle strength and functional control may mitigate the progression of foot deformity and disability. Ensuring correct exercise technique is challenging due to the specificity of muscle activation required to complete some foot exercises. Biofeedback has been used to improve adherence, muscle activity and movement patterns. We investigated the feasibility of using a novel medical device, known as “Archercise”, to provide real-time biofeedback of correct arch movement via pressure change in an inflatable bladder, and foot location adherence via sensors embedded in a footplate during four-foot exercises.

Methods

Thirty adults (63% female, aged 23–68 years) performed four-foot exercises twice on the Archercise sensor footplate alone and then with biofeedback. One-way repeated measures ANOVA with pairwise comparisons were computed to assess the consistency of the exercise protocol between trial 1 and trial 2 (prior to biofeedback), and the effectiveness of the Archercise biofeedback device between trial 2 and trial 3 (with biofeedback). Outcome measures were: Arch movement exercises of arch elevation and lowering speed, controlled arch elevation, controlled arch lowering, endurance of arch elevation; Foot location adherence was determined by percentage of time the great toe, fifth toe and heel contacted footplate sensors during testing and were analysed with paired sample t-tests. Participant survey comments on the use of Archercise with biofeedback were reported thematically.

Results

Seventeen (89%) arch movement and foot location variables were collected consistently with Archercise during the foot exercises. Archercise with biofeedback improved foot location adherence for all exercises (p = 0.003–0.008), coefficient of determination for controlled arch elevation (p < 0.0001) and endurance area ratio (p = 0.001). Twenty-nine (97%) participants reported Archercise with biofeedback, helped correct exercise performance.

Conclusions

Archercise is a feasible biofeedback device to assist healthy participants without foot pathologies perform foot doming exercises.

Trial registration

Australian New Zealand Clinical Trials Registry (ANZCTR): 12616001559404. Registered 11 November 2016, http://www.ANZCTR.org.au/ACTRN12616001559404p.aspx

Diagnostic accuracy of lumbopelvic motor control tests using pressure biofeedback unit in professional swimmers: A cross-sectional study

Hypothesis

To determine the effect of receiving the visual feedback of the sphygmomanometer on lumbopelvic motor control (LPMC) tests in professional swimmers.

Method

31 professional swimmers to participate in the study. The outcome was maximum absolute mmHg variation in the pressure biofeedback unit's manometer with and without visual feedback on four LPMC tests.

Results

Test scores were significantly affected by visual feedback F = 10.07, p = 0.002, η² _p = 0.117 and the type of test F = 32.53, p < 0.001, η² _p = 0.300.

Conclusion

Visual feedback has a positive effect on the Active Straight Leg Raise Test (ASLR), the Knee Lift Abdominal Test (KLAT) scores completed by professional swimmers.

Pressure biofeedback unit to assess and train lumbopelvic stability in supine individuals with chronic low back pain

[Purpose] To determine if pressure biofeedback unit readings are related to abdominal muscle activation and centre of pressure displacement as well as to test the effects of using it as a biofeedback tool to control lumbopelvic motion. [Participants and Methods] Eighteen volunteers with chronic nonspecific low back pain (21.28 ± 1.41 years old) who performed an active straight leg raising (dynamic postural challenge) with and without pressure biofeedback. Changes in the pressure biofeedback unit and on centre of pressure displacement were assessed, as well as bilateral electromyographic abdominal muscle activity. Participants were not allowed to use a Valsalva manoeuvre. [Results] Pressure variation was not significantly correlated with abdominal muscle activity or with mediolateral centre of pressure displacement. When used as a biofeedback instrument, there was a significant increase in almost all abdominal muscles activity as well as a significant decrease in pressure variation and in mediolateral centre of pressure displacement while performing an active straight leg raising with a normal breathing pattern. [Conclusion] Despite not being an indicator of abdominal muscle activity or mediolateral load transfer in the supine position, the pressure biofeedback unit could have great relevance when used in the clinic for biofeedback purposes in individuals with low back pain.

Audiovisual Biofeedback-Based Trunk Stabilization Training Using a Pressure Biofeedback System in Stroke Patients: A Randomized, Single-Blinded Study

The purpose of this study was to assess the effects of audiovisual biofeedback-based trunk stabilization training using a pressure biofeedback system (PBS) in stroke patients. Forty-three chronic stroke patients, who had experienced a stroke more than 6 months ago and were able to sit and walk independently, participated in this study. The subjects were randomly allocated to an experimental group (n = 21) or a control group (n = 22). The experimental group participated in audiovisual biofeedback-based trunk stabilization training for 50 minutes/day, 5 days/week, for 6 weeks. The control group underwent trunk stabilization training without any biofeedback. The primary outcome of this study was the thickness of the trunk muscles. The secondary outcomes included static sitting balance ability and dynamic sitting balance ability. The thickness of the trunk muscles, static sitting balance ability, and dynamic sitting balance ability were significantly improved in the experimental group compared to the control group (p < 0.05). The present study showed that trunk stabilization training using a PBS had a positive effect on the contracted ratio of trunk muscles and balance ability. By providing audiovisual feedback, the PBS enables accurate and effective training of the trunk muscles, and it is an effective method for trunk stabilization.

Fitz-Hugh-Curtis syndrome: clinical diagnostic value of dynamic enhanced MSCT

[Purpose] This study aimed to investigate the clinical diagnostic value of dynamic enhanced multislice computed tomography (MSCT) for Fitz-Hugh-Curtis syndrome (FHCS). [Subjects and Methods] This study retrospectively analyzed the clinical features and manifestations of scanning and dynamic enhanced MSCT in 19 patients with FHCS. [Results] MSCT scans showed different degrees of liver capsule thickness in the lesion area: seven cases of sub-capsular effusion and three cases with a small amount of pleural effusion; thickness of the liver capsular arterial phase showing significant enhancement in 17 cases, and slight enhancement in two; portal venous and delayed phase enhancement decreased with no clear boundary of the liver parenchyma; and adjacent hepatic parenchymal involvement in five cases, in which the arterial phase appeared to have patchy or triangular enhancement, and unclear portal vein and delayed phase imaging findings. MSCT revealed pelvic inflammatory disease in 14 cases, peritonitis in two, endometritis combined with bilateral ovarian abscesses in two, and a tube-ovarian abscess in one. [Conclusion] Dynamic enhanced MSCT can accurately display liver capsule lesions and possible pelvic inflammatory diseases related to FHCS, suggest the infection source, and have high application value for making early, accurate diagnoses and improved prognosis.

Effects of performing an abdominal hollowing exercise on trunk muscle activity during curl-up exercise on an unstable surface

[Purpose] The purpose of this study was to investigate the effects of the abdominal hollowing exercise on trunk muscle activity during the curl-up exercise on an unstable surface by measuring electromyography (EMG) activity. [Subjects] Fourteen young healthy adults (nine male, five female) voluntarily participated in this study. [Methods] Each subject was asked to perform a curl-up exercise on two supporting surfaces (stable and unstable surfaces) combined with the abdominal hollowing exercise on an unstable surface. The muscle activities of the rectus abdominis (RA), external oblique (EO), internal oblique (IO), and transverse abdominis (TrA) were measured using surface EMG during performance of the curl-up exercise. [Results] The EMG activity of the RA and EO was significantly higher on an unstable surface than on a stable surface during the curl-up exercise. The EMG activities of the TrA and IO were greater in combination with the abdominal hollowing exercise on an unstable surface than during the curl-up exercise on both a stable and unstable surface. [Conclusion] These findings suggest that the local trunk muscle activity during the curl-up exercise is more strongly affected by combination with the abdominal hollowing exercise than by performance on an unstable supporting surface.

Reliability of the modified Thomas test using a lumbo-plevic stabilization

[Purpose] The purpose of this study was to examine the test-retest reliability of the modified Thomas test using lumbo-pelvic stabilization. [Subjects] Thirteen subjects (male=10, female=3) with hip flexor tightness voluntarily participated in the study. [Methods] The participants underwent the modified Thomas test under three conditions: 1) the general modified Thomas test (GM), 2) active lumbo-pelvic stabilization (ALS), and 3) passive lumbo-pelvic stabilization (PLS). Intra-class correlation coefficients (ICC) were used to determine the test-retest reliability of the knee joint angle measurement under three conditions. The standard error of measurement (SEM) and minimal detectable difference (95% confidence interval) (MDD⁹⁵) were calculated for each measurement to assess absolute consistency. [Results] The ALS (ICC = 0.99) and PLS (ICC = 0.98) methods for the modified Thomas test were more reliable than GM method (ICC = 0.97). The MDD⁹⁵ score for the ALS method, 2.35 degrees, indicated that a real difference existed between two testing sessions compared with the scores for the PLS (3.70 degrees) and GM methods (4.17 degrees) [Conclusion] Lumbo-pelvic stabilization is one of the considerations for precise measurement and may help to minimize measurement error when evaluating hip flexor tightness using the modified Thomas test.