The effect of electromyography triggered electrical stimulation to abdominal muscles on sitting balance, respiratory functions, and abdominal muscle thickness in complete spinal cord injury: a randomized controlled trial.

Complete thoracic spinal cord injury (SCI) results in a loss of innervation to the abdominal muscles, which affects trunk stability and performance of activities of daily living from a sitting position. Respiratory function is also affected, leading to frequent pulmonary complications. Given the importance of trunk stability and respiratory function, we investigated the effects of electromyography triggered electrical stimulation (EMG-ES) applied to the abdominal muscles on sitting balance, respiratory functions and abdominal muscle thickness in individuals with complete thoracic SCI. This randomized controlled study included 34 participants with complete thoracic SCI who were randomly allocated to the experimental group ( n  = 17) and the control group ( n  = 17). During the 4-week intervention period, the experimental group received EMG-ES to their abdominal muscles, while the control group received isometric abdominal exercises three times per week. Both groups continued with their routine rehabilitation program (active or passive range of motion exercises, stretching, and balance coordination exercises). The primary outcome measures were the modified functional reach test (mFRT) and trunk control test (TCT). Secondary outcome measures included a pulmonary function test (PFT) and the bilateral abdominal muscle thicknesses using ultrasonography. At the end of the study, the experimental group showed significantly greater improvements in both primary outcomes. The mean difference in pre-post changes between the groups for the mFRT area was 242.8 cm² [95% confidence interval (CI): 181.3-329.8; effect size 0.92; P  < 0.001] and 5.0 points for TCT (95% CI: 3.9-6.0; effect size 0.98, P  < 0.001). The increase in the abdominal muscle thickness was also significantly greater in the experimental group ( P  < 0.001) without significant differences in the PFT ( P  > 0.05). We conclude that adding EMG-ES of abdominal muscles may further improve sitting balance and abdominal muscle thickness in individuals with complete thoracic SCI.

Ultrasound-Guided Transversus Abdominis Plane Blocks Versus Local Infiltration Anesthesia on Postanesthesia Care Unit Pain Control in Patients Undergoing Abdominoplasty.

GOALS/PURPOSE: The goal of this study was to compare ultrasound-guided transversus abdominis plane (TAP) blocks to local infiltration anesthesia with or without blind rectus sheath blocks in patients who underwent abdominoplasty at an outpatient surgery center. METHODS/TECHNIQUE: A retrospective review was conducted of patients who underwent outpatient abdominoplasty performed by the senior surgeon (J.T.L.). Group 1 received local infiltration anesthesia with or without blind rectus sheath blocks between April 2009 and December 2013. Group 2 received surgeon-led, intraoperative, ultrasound-guided, 4-quadrant TAP blocks between January 2014 and December 2021. Outcomes measured were opioid utilization (morphine milligram equivalents), pain level at discharge, and time spent in postanesthesia care unit (PACU). RESULTS: Sixty patients in each of the 2 study groups met the study criteria for a total of 120 patients. The study groups were similar except for a lower average age in group 1. Patients who received TAP blocks (group 2) had significantly lower morphine milligram equivalent requirements in the PACU (3.07 vs 8.93, P = 0.0001) and required a shorter stay in PACU (95.4 vs 117.18 minutes, P = 0.0001). There were no significant differences in pain level at discharge. CONCLUSIONS: Surgeon-led, intraoperative, ultrasound-guided, 4-quadrant TAP blocks statistically significantly reduced opioid utilization in PACU by 65.6% and average patient time in the PACU by 18.5% (21.8 minutes).

Providing Visual Biofeedback Using Brightness Mode Ultrasound During a Golf Swing.

Using ultrasound biofeedback in conjunction with verbal cueing can increase muscle thickness more than verbal cueing alone and may augment traditional rehabilitation techniques in an athletic, physically active population. Brightness mode (B-mode) ultrasound can be applied using frame-by-frame analysis synchronized with video to understand muscle thickness changes during these dynamic tasks. Visual biofeedback with ultrasound has been established in static positions for the muscles of the lateral abdominal wall. However, by securing the transducer to the abdomen using an elastic belt and foam block, biofeedback can be applied during more specific tasks prevalent in lifetime sports, such as golf. To analyze muscle activity during a golf swing, muscle thickness changes can be compared. The thickness must increase throughout the task, indicating that the muscle is more active. This methodology allows clinicians to immediately replay ultrasound videos for patients as a visual tool to instruct proper activity of the muscles of interest. For example, ultrasound can be used to target the external and internal obliques, which play an important role in swinging a golf club or any other rotational sport or activity. This methodology aims to increase oblique muscle thickness during the golf swing. Additionally, the timing of muscle contraction can be targeted by instructing the patient to contract the abdominal muscles at specific time points, such as the beginning of the downswing, with the goal of improving muscle firing patterns during tasks.

Effect of Motor Control Training on Trunk Muscle Morphometry, Pain, and Disability in People With Chronic Low Back Pain: A Systematic Review and Meta-Analysis.

OBJECTIVE: The aim of this systematic review and meta-analysis was to study the effects of motor control training (MCT) on trunk muscle morphometry measured by ultrasound imaging and pain and disability in individuals with chronic low back pain. METHODS: PubMed, Web of Science, Scopus, and Cochrane Library databases were searched from study inception until January 2021. Randomized control trials evaluating both muscle morphometry and pain or disability in individuals with chronic low back pain were included. Study selection, data extraction, and quality assessment were performed by 2 reviewers independently. Modified Downs and Black tool and the Grading of Recommendations Assessment, Development and Evaluation approach were used to assess the risk of bias and quality of evidence, respectively. A meta-analysis was performed using a random effects model with mean difference or standardized mean difference (SMD). RESULTS: Of 3459 studies initially identified, 15 studies were included, and 13 studies were selected for meta-analysis. The results revealed no differences in the resting thickness of the transversus abdominis, internal and external oblique, and lumbar multifidus muscles in studies that compared MCT with other interventions. The transversus abdominis muscles contraction ratio was greater (SMD = 0.93; 95% confidence interval [CI], -0.0 to 1.85) and lower pain (weighted mean difference: -1.07 cm; 95% CI, -1.91 to -0.22 cm; P = .01) and disability (SMD = -0.86; 95% CI, -1.42 to -0. 29; P < .01) scores were found in the groups who underwent MCT compared with other interventions. CONCLUSION: This systematic review and meta-analysis found that motor control exercise training increased the transverse abdominis contraction ratio (muscle activation) and improved the level of pain and disability compared to other interventions in people with chronic low back pain. However, motor control exercise training was not superior to other interventions in increasing the resting thickness of deep abdominal and lumbar multifidus muscles in intervention times less than 12 weeks.

Robot-assisted vs ultrasonography-guided transversus abdominis plane (TAP) block vs local anaesthesia in urology: results of the UROTAP randomized trial.

OBJECTIVES: To prospectively analyse robotically administered transperitoneal transversus abdominis plane (robot-assisted transversus abdominis plane [RTAP]) compared with both ultrasonography-guided transversus abdominis plane (UTAP) and local anaesthesia (LA) with regard to pain control and narcotic use in patients undergoing robot-assisted prostatectomy (RARP) or robot-assisted partial nephrectomy (RAPN). SUBJECTS/PATIENTS AND METHODS: Patients undergoing RARP or RAPN were randomized in a single-blind 2:2:1 fashion to RTAP:UTAP:LA, with the study powered to evaluate superiority of UTAP to LA and non-inferiority of RTAP to UTAP. We compared time to deliver the block, operating room time, postoperative pain scores using the visual analogue scale, and intra-operative and postoperative analgesia consumption. RESULTS: A total of 143 patients were randomized and received treatment. There was no significant difference in patient baseline characteristics. UTAP did not demonstrate superiority to LA in terms of pain control. RTAP and LA were faster to administer than UTAP (time to perform block 2.5 vs 2.5 vs 6.25 min; P < 0.001). There was no difference in postoperative narcotic, acetaminophen, ketorolac or ondansetron requirements among the three groups (P > 0.05). The study was terminated early due to the unexpected efficacy of LA. CONCLUSION: This study showed that UTAP and RTAP do not provide superior pain control to LA. The efficiency, effectiveness, and ease of administration of LA make it an excellent option for first-line therapy for postoperative analgesia.

Effects of mouthpiece shape and expiratory threshold loading on contraction of the lateral abdominal muscles: A cross-sectional study.

BACKGROUND: Expiratory tasks may facilitate transversus abdominis (TrA) activity for spinal stabilization. The purpose of this study was to verify whether a combination of pursed-lip breathing (PLB) and use of an expiratory threshold loading (ETL) device to increase expiratory resistance would promote TrA contraction comparable to that for a stabilization exercise. METHODS: Twenty healthy men performed expiratory tasks or an abdominal drawing-in maneuver (ADIM). Expiratory tasks comprised combinations of ETL settings with 0%, 5%, or 15% of maximum expiratory pressure, and mouthpieces with a normal shape or pursed-lip shape. B-mode ultrasound imaging of the TrA, internal oblique, and external oblique muscles was performed to determine percentage changes in muscle thickness. Percentage changes among tasks were statistically compared for each muscle. FINDINGS: TrA thickness increased with normal lips at 15% ETL, with PLB with 5% ETL, and with ADIM (p < 0.01 each). Internal oblique thickness increased under all PLB conditions (p < 0.01 each). No significant differences in external oblique thickness were seen for any tasks. The total thickness of the lateral abdominal muscles was significantly increased not only for 15% ETL tasks and ADIM, but also for PLB with 5% ETL (p < 0.02 each). INTERPRETATION: These results indicated that PLB with 5% ETL could facilitate the same level of TrA activity as the ADIM. PLB with 5% ETL was the only task that simultaneously increased overall lateral abdominal muscles, including the internal obliques, and might be readily applicable in clinical situations.

Comparison of two different feedback techniques for activating the transversus abdominis: An observational study.

BACKGROUND: The transversus abdominis (TrA) is an important muscle for spinal stabilization. The abdominal draw-in maneuver (ADIM) is a method that selectively activates the TrA without overactivation of the external oblique (EO) and internal oblique (IO). Individuals with low back pain may have trouble in understanding proper contraction of the TrA. OBJECTIVE: The aim of this study was to investigate the differences between two feedback techniques to re-educate the TrA. METHODS: One hundred eighty healthy volunteers (123 female, 57 male) were randomized into two groups. The ADIM was performed with different feedback methods: conventional (verbal and tactile) feedback and visual feedback from real-time ultrasound images. RESULTS: A within-group comparison revealed a significant increase in the thickness of the TrA, IO, and EO during the ADIM (p< 0.001) in both groups. The mean change (SD) in the thickness of the TrA and IO between rest and the ADIM was an increase of 2.541.25 and 1.882.14 in group 1 and 1.821.27 and 1.241.87 in group 2, respectively (p< 0.001). No significant differences were observed in EO thickness between the two groups. CONCLUSIONS: Although visual biofeedback shows a greater effect on ADIM training, both approaches are applicable, and clinicians may decide on which to use based on their clinical environment and experience.

Comparison of the Pressure Biofeedback Unit and Real-Time Ultrasound Imaging as Feedback Tools to Contract the Transversus Abdominis Muscle: A Randomized Controlled Trial in Healthy Older Adults.

BACKGROUND AND PURPOSE: The transversus abdominis (TrA) is a key muscle for lumbar stabilization and is often retrained in physical therapy. Feedback tools, such as the pressure biofeedback unit (PBU) and rehabilitative ultrasound imaging (RUSI), are frequently used by physical therapists to train their patients and improve their patients' ability to contract this muscle. However, the effect of these tools in rehabilitating the TrA in older adults remains to be demonstrated, as is their efficiency in transferring the skill of recruiting the TrA from a supine position to a standing position.The objective of the study was to compare the immediate effectiveness of the PBU and RUSI to reeducate the TrA muscle in a population of asymptomatic older adults (without pain). METHODS: Forty participants were randomized into 2 groups (RUSI or PBU). The intervention included a training session involving 15 TrA contractions held for 10 seconds with the corresponding feedback device. The dependent variable, TrA thickness (a muscle activation indicator), was measured using ultrasound images before and after the intervention in a supine and standing position. Nonparametric analyses were used for inter- and intragroup comparisons. RESULTS AND DISCUSSION: The results showed no between-group differences in TrA activation ratio (AR) in the supine or standing position (supine AR: TrA RUSI thickness change P = .53 vs PBU thickness change P = .73, comparison between groups P = .51; standing AR: TrA RUSI thickness change P = .003 vs PBU thickness change P = .10; comparison between groups P = .61). However, the change in TrA thickness compared to the other abdominal wall muscles in a standing position was significantly less post-intervention for the RUSI group only (RUSI P = .006 vs PBU P = .72). Both groups remained similar post-intervention for this outcome (P = .20). CONCLUSIONS: Neither the RUSI nor the PBU seems to have the desired effect on the activation of TrA in asymptomatic older adults.

Comparison of linea alba length and core-muscles engagement during core and lower back orientated exercises.

BACKGROUND: A comparison of Linea Alba (LA) length and engagement of the Transverse Abdominis (TrA), External Oblique (EO) and Internal Oblique (IO) between core-orientated and lower back orientated exercises (e.g. glute bridge and hip extension) is lacking. Therefore, the aim of this study was to compare the length of the LA and the engagement of TrA, EO and IO when performing the prone plank, bird dog, dead bug, lateral plank, glute bridge and hip extension. METHODS: Thirteen apparently healthy participants volunteered to this study. Ultrasound scanning of the anterior and antero-lateral abdominal walls at baseline and whilst performing prone plank, bird dog, dead bug, lateral plank, glute bridge and hip extension exercises was performed. LA length and thickness of the TrA, EO and IO were measured from ultrasound images. RESULTS: LA length (p = 0.77) and TrA thickness (p = 0.23) were not different between exercises. EO thickness was larger for the lateral plank compared to the bird dog (p = 0.01, d = 1.73), glute bridge (p < 0.01, d = 2.64), and hip extension (p < 0.01, d = 1.89). The dead bug was also larger in comparison to the glute bridge (p < 0.01, d = 2.05) and to the hip extension (p = 0.01, d = 1.45). For the IO thickness, the lateral plank was larger than the bird dog (p = 0.03, d = 1.21) and the dead bug (p = 0.04, d = 1.12). CONCLUSION: No difference was observed between exercises for the length of the LA or for the thickness of the TrA, which suggests that this muscle is similarly engaged in the assessed exercises, leading to a consistent stretch for the LA.

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

INTRODUCTION: Growing 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. METHODS: Thirty-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. RESULTS: Overall, 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). DISCUSSION: The different sources of error were distributed unequally across RUSI measures, pointing to different measurement strategies to mitigate the underlying errors. CONCLUSIONS: The 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.

The influence of rotational movement exercise on the abdominal muscle thickness and trunk mobility - Randomized control trial.

BACKGROUND: Trunk rotations are important functional movements which form the foundations of human motion pattern, especially in the functions of walking and running. They prevent the functional impairments and structural lesions resulting from axial overloading in static positions such as sitting. OBJECTIVES: The aim of the study was to assess the influence of rotational movement training exercises on the abdominal muscle thickness and spinal mobility range. STUDY DESIGN: Randomized controlled trial. METHODS: The study involved 73 individuals aged 18-45. The subjects were randomly divided into two groups. The study group (TG) comprised 40 people who performed rotational movement exercises over the period of 4 weeks (16 training sessions). In the control group (CG) the training was not applied. Changes in the thickness of selected abdominal muscles on ultrasound imaging were evaluated, as well as trunk mobility, based on the trunk lateral flexion test. RESULTS: The analysis of the obtained data has demonstrated a statistically significant increase in the thickness of the abdominal internal (IO) (p < 0.05) and external oblique muscles (EO) (p < 0.001) in the study group (TG) between measurements I and II, and measurements I and III. A similar increase in the thickness was found in the summation measurement of TrA + IO + EO. Bilateral increase in the trunk lateral flexion range in the frontal plane has also been noted. CONCLUSIONS: Rotational movement training of the trunk leads to an increase in the thickness of the abdominal oblique muscles. Rotational movement exercise training increases trunk mobility in the frontal plane.

Ultrasound Imaging as a Visual Biofeedback Tool in Rehabilitation: An Updated Systematic Review.

Rehabilitative ultrasound imaging (RUSI) is used by physical therapists as a feedback tool for measuring changes in muscle morphology during therapeutic interventions such as motor control exercises (MCE). However, a structured overview of its efficacy is lacking. We aimed to systematically review the efficacy of RUSI for improving MCE programs compared with no feedback and other feedback methods. MEDLINE, PubMed, SCOPUS and Web of Science databases were searched for studies evaluating efficacy data of RUSI to improve muscular morphology, quality, and/or function of skeletal muscles and MCE success. Eleven studies analyzing RUSI feedback during MCE were included. Most studies showed acceptable methodological quality. Seven studies assessed abdominal wall muscles, one assessed pelvic floor muscles, one serratus anterior muscle, and two lumbar multifidi. Eight studies involved healthy subjects and three studies clinical populations. Eight studies assessed muscle thickness and pressure differences during MCE, two assessed the number of trials needed to successfully perform MCE, three assessed the retain success, seven assessed the muscle activity with electromyography and one assessed clinical severity outcomes. Visual RUSI feedback seems to be more effective than tactile and/or verbal biofeedback for improving MCE performance and retention success, but no differences with pressure unit biofeedback were found.

Reliability of ultrasound measurement of the lateral abdominal and lumbar multifidus muscles in individuals with chronic low back pain: A cross-sectional test-retest study.

OBJECTIVES: Ultrasound (US) imaging has been suggested to evaluate the morphology and function of trunk muscles; however, little is known about the reliability of the US measures in patients with chronic low back pain (CLBP). This study aimed to evaluate intrarater reliability of US imaging of the lateral abdominal and lumbar multifidus muscles in individuals with nonspecific CLBP. METHODS: In this cross-sectional study, intrarater within-day and between-day reliability of US measurements of the transversus abdominis, internal oblique, external oblique and lumbar multifidus (at the L3-L4, L4-L5, and L5-S1 levels) muscles were obtained on both sides. The resting and contracted thickness and contraction ratio of each muscle were measured in 21 individuals with nonspecific CLBP. RESULTS: All US measurements of the lateral abdominal and lumbar multifidus muscles demonstrated good to excellent within-day (Intraclass correlation coefficients (ICCs: 0.80-0.98) and between-day (ICCs: 0.80-0.97) reliability. The standard error of the measurement (SEMs) and minimal detectable change (MDCs) of the lateral abdominal muscles on both sides ranged 0.5-1.6 mm and 0.4-4.4 mm, respectively. The SEMs and MDCs of the LM muscles on both sides ranged 1.1-2.7 mm and 2.86-7.49 mm, respectively. CONCLUSION: The findings indicate that US imaging has good to high intrarater within- and between-day reliability for assessing absolute thickness and contraction ratio of the trunk muscles on both right and left sides in patients with nonspecific CLBP. The vertical alignment of the US transducer is a reliable method for assessing the lateral abdominal muscles.

Breathing Exercise Called the Maximal Abdominal Contraction Maneuver.

Background and objectives: The maximal abdominal contraction maneuver (MACM) was designed as an effective and efficient breathing exercise to increase the stability of the spinal joint. However, it has not been determined whether MACM is more effective and efficient than the maximal expiration method. Thus, the present study was undertaken to investigate whole abdominal muscle thickness changes after MACM. Materials and Methods: Thirty healthy subjects (17 males and 13 females) participated in this study. An experimental comparison between MACM and the maximal expiration task was conducted by measuring the change of abdominal muscle thickness such as the transverse abdominis (TrA), internal oblique (IO), external oblique (EO) and rectus abdominis (RA) using ultrasound images. Results: The results indicated that MACM resulted in significantly greater muscle thickness increases of the TrA and RA than the maximal expiration exercise (p < 0.05). Conclusion: MACM provided better exercise than the maximal expiration exercise in terms of increasing spine stability, at least from a co-contraction perspective.

Effect of real-time ultrasound imaging for biofeedback on trunk muscle contraction in healthy subjects: a preliminary study.

BACKGROUND: Real-time ultrasound imaging (RUSI) has been increasingly used as a form of biofeedback when instructing and re-training muscle contraction. However, the effectiveness of the RUSI on a single sustained contraction of the lumbar multifidus (LM) and transversus abdominis (TrA) has rarely been reported. This preliminary study aimed to determine if the use of RUSI, as visual biofeedback, could enhance the ability of activation and continuous contraction of the trunk muscles including LM and TrA. METHODS: Forty healthy individuals were included and randomly assigned into the experimental group and control group. All subjects performed a preferential activation of the LM and/or TrA (maintained the constraction of LM and/or TrA for 30 s and then relaxed for 2 min), while those in the experimental group also received visual feedback provided by RUSI. The thickness of LM and/or TrA at rest and during contraction (Tc-max, T15s, and T30s) were extracted and recorded. The experiment was repeated three times. RESULTS: No significant differences were found in the thickness of LM at rest (P > 0.999), Tc-max (P > 0.999), and T15s (P = 0.414) between the two groups. However, the ability to recruit LM muscle contraction differed between groups at T30s (P = 0.006), with subjects in the experimental group that received visual ultrasound biofeedback maintaining a relative maximum contraction. Besides, no significant differences were found in the TrA muscle thickness at rest (P > 0.999) and Tc-max (P > 0.999) between the two groups. However, significant differences of contraction thickness were found at T15s (P = 0.031) and T30s (P = 0.010) between the two groups during the Abdominal Drawing-in Maneuver (ADIM), with greater TrA muscle contraction thickness in the experimental group. CONCLUSIONS: RUSI can be used to provide visual biofeedback, which can promote continuous contraction, and improve the ability to activate the LM and TrA muscles in healthy subjects.

Ultrasound-guided transversus abdominis plane block vs trigger point injections for chronic abdominal wall pain: a randomized clinical trial.

ABSTRACT: The primary aim of this randomized clinical trial is to investigate the effects of ultrasound-guided transversus abdominis plane (TAP) vs ultrasound-guided trigger point injections (TPIs) on numerical rating scale pain scores at month 3 follow-up in patients with a chronic abdominal wall pain. The primary outcome measure was the difference in mean numeric rating scale pain scores between the TAP and TPI groups at month 3 in an intent-to-treat (ITT) analysis. A total of 60 patients were randomized 1:1 to receive an ultrasound-guided TAP block (n = 30) or an ultrasound-guided TPI (n = 30). No significant group differences in baseline demographic or clinical characteristics were observed. The mean baseline pain score for the TAP and TPI groups was 5.5 and 4.7, respectively. In the ITT analysis at month 3, the between-group difference in pain scores was 1.7 (95% confidence interval, 0.3-3.0) favoring the TPI group. In a secondary per-protocol analysis, the between-group difference in pain scores was 1.8 (95% confidence interval, 0.4-3.2) favoring the TPI group. For the ITT and per-protocol analyses, the group differences in pain scores were consistent with a medium effect size. The main finding of this randomized clinical trial is that adults with chronic abdominal wall pain who received a TPI reported significantly lower pain scores at month 3 follow-up compared with patients who received a TAP block.

Changes in the lateral abdominal wall following endoscopic subcutaneous anterior component separation.

PURPOSE: Although changes in lateral abdominal wall musculature after posterior component separation with transversus abdominis release have been investigated, the effects of endoscopic subcutaneous anterior component separation (ES-ACS) on postoperative muscle anatomy have not been evaluated. The purpose of this study was to evaluate changes in the lateral abdominal muscles after ES-ACS. METHODS: Computed tomography (CT) images of patients who underwent ES-ACS were retrospectively evaluated. Lateral abdominal wall thickness and external oblique displacement were measured at the level of fixed retroperitoneal structures. Measurements on the ES-ACS side were compared with those on the contralateral undivided side or with preoperative images in patients with bilateral procedures. RESULTS: Fifteen patients met the criteria for study inclusion. Most patients (n = 13, 86.7%) underwent unilateral ES-ACS. The most commonly performed procedure was laparoscopic intraperitoneal onlay mesh-plus hernia repair (n = 12, 80.0%; the remaining patients underwent open repair). The Mean defect width was 8.4 cm (range 6-15 cm). There was no difference in the thickness of the lateral abdominal musculature between ES-ACS and undivided sides. There was a significant lateral displacement of the external oblique muscle from the lateral edge of the rectus abdominis on the ES-ACS side (mean distance 3.7 cm; p = 0.0006). No midline hernia recurrences, iatrogenic linea semilunaris hernias, or lateral eventrations were observed during a mean follow-up period of 2.6 years (range 0.5-7.4 years). CONCLUSION: ES-ACS resulted in no atrophy of the lateral abdominal muscles in long-term CT follow-up. The procedure is a safe and effective adjunct to complex hernia repair in selected patients.

Effects of core stabilization exercises on thickness and activity of trunk and hip muscles in subjects with nonspecific chronic low back pain.

BACKGROUND: Changes in trunk and hip muscles are believed to be important in subjects with nonspecific chronic low back pain (NSCLBP), but little is known about specific changes, or how they might be affected by core stabilization exercises. The aim of this study was to compare six key muscles before and after these exercises. METHODS: Thirty two NSCLBP patients were assigned randomly into two groups: exercise (n = 17) and control (n = 15). On 5 days per week for 4 weeks, the Exercise group performed 16 core stabilization exercises and the Control group received transcutaneous electrical nerve stimulation and a 'hot-pack'. Surface electromyography (EMG) was used to assess maximum bilateral activity of transversus abdominis (TrA), multifidus (MF) and gluteus maximus (Gmax) muscles. Ultrasound imaging was used to measure the rest and contracted thickness of these muscles. Pain and disability were assessed using a visual analogue scale (VAS) and the Oswestry Disability Index. RESULTS: When left and right-side muscle data were combined, two-way ANOVAs showed a nonsignificant interaction effect for all dependent variables (P > 0.05), significant time effects on resting muscle thickness for TrA (P = 0.01), MF (P = 0.041) and Gmax (P = 0.003), EMG signals of TrA (P = 0.038), pain and disability (P = 0.000). There were a significant group effect on contracted thickness for TrA (P = 0.032) and Gmax (P = 0.026) and disability (P = 0.017). CONCLUSIONS: Core stabilization exercises increased contracted thickness of TrA and Gmax muscles and decreased disability in subjects with NSCLBP.

Structural remodelling of the lumbar multifidus, thoracolumbar fascia and lateral abdominal wall perimuscular connective tissues: A cross-sectional and comparative ultrasound study.

INTRODUCTION: With low back pain (LBP), remodelling of the lumbar soft tissues involves both trunk muscles and neighbouring passive connective tissues. The aim of the present study was to compare three quantitative measures of these tissues, using ultrasound imaging (USI), among healthy controls and individuals with LBP. METHODS: USI measures from 30 healthy subjects and 34 patients with non-acute LBP were compared between groups and sexes. The measures employed were (1) lumbar multifidus echogenicity (fatty/fibrosis infiltration) at three vertebral levels; (2) posterior layer thickness of the thoracolumbar fascia, and (3) thickness of the perimuscular tissues surrounding the external oblique, internal oblique and transversus abdominis (TrA). RESULTS: USI measures of (1) multifidus echogenicity showed statistically significant changes between vertebral levels and sexes (females > males; p = 0.02); (2) differences in thoracolumbar fascia thickness approached statistical significance between groups (LBP > controls; p = 0.09) and sexes (females < males; p = 0.07); and (3) perimuscular tissue surrounding the TrA was significantly thinner (p ≤ 0.001) in patients with LBP compared to controls. DISCUSSION: The thinner perimuscular tissues surrounding the TrA in patients with LBP is a new finding, concurring with previous findings with regard to the lower activation of this deep muscle as well as more recent findings on other perimuscular tissue. CONCLUSION: Overall, USI measures were sensitive to different potential changes (pain status, sex, vertebral level), and this is useful in studying the remodelling of various soft tissues of the trunk.

Transverse abdominis activity and ultrasound biofeedback in college golfers with and without low back pain.

OBJECTIVES: To compare transverse abdominis (TrA) muscle activity in college golfers with and without a history of low back pain (LBP) and examine the effects of ultrasound biofeedback and a functional golf-setup position on TrA activity. DESIGN: Crossover study. SETTING: Laboratory. PARTICIPANTS: Thirty-two (n = 32) collegiate golfers were stratified into either the LBP group (n = 16, 4.6 ± 4.5 LBP episodes) or non-LBP group (n = 16, 0.1 ± 0.3 LBP episodes) based on LBP episodes in the last 6-months. MAIN OUTCOME MEASURES: Ultrasound measures of TrA activity were performed during standard contractions and contractions with ultrasound biofeedback. Contraction-type order was randomized between two visits. Testing was performed in two positions, supine and golf-setup positions. RESULTS: We observed no significant differences in TrA activity between the LBP and non-LBP groups. Overall, TrA activity was greater during biofeedback contractions compared to standard contractions, and TrA activity was lower in the golf-setup position compared to the supine position. CONCLUSIONS: We observed no differences in TrA activity between college golfers with and without LBP. College golfers with and without LBP demonstrated a greater ability to contract their TrA with real-time ultrasound biofeedback and a lower ability to contract their TrA in the functional golf-setup position compared to the traditional supine position.