Internal Oblique Research Articles

A Comparative Study Between Ultrasound-Guided Ilioingunial/Iliohypogastric Nerve Block versus Transverse Abdominis Plane Block in Patients Undergoing Oblique Inguinal Hernia Repair

Abstract Background Poorly controlled acute pain after abdominal surgery is related to somatic pain signals derived from the abdominal wall and is associated with a variety of unwanted post-operative consequences, including patient suffering, distress, respiratory complications, delirium, myocardial ischemia and prolonged hospital stay. Objective Regional anesthesia by (Ultrasound guided (US) Transversus abdominis plane block (TAP) or Ultrasound guided ilioinguinal and iliohypogastric nerves (IIN+IHN) block may be used as components of multimodal anesthesia with a comparable effect. In the present study, Bupivacaine is used to compare between them following inguinal hernia repair. Patients and Methods The study was conducted on 60 randomly chosen patients aged above 18 years, American Society of Anesthesiologists (ASA) class I or II scheduled for elective unilateral open inguinal hernia repair under general anesthesia, in Ain Shams University Hospitals after approval of the medical ethical committee. They were allocated in two groups. TAP block Group: received general anesthesia and (0.2 mL/kg of 0.25% bupivacaine per side), by midaxillary approach, under ultrasound guidance, the probe was placed transversely between the iliac crest and costal margin. Ilioinguinal/ iliohypogastric nerves block group: received general anesthesia, with (0.2 mL/kg of 0.25% bupivacaine per side). The inferior portion of linear ultrasound transducer will be placed over the anterior superior iliac spine with the superior margin of the transducer pointed directly in an oblique plane toward the umbilicus. The superior margin of the ultrasound transducer was slowly rotated superiorly and inferiorly until the fascial plane between the internal oblique and transverse abdominis muscle is identified. Results The results of the study revealed that patients received IIN+IHN block had significantly lower pain scores at 8, 12, 16, 20, and 24 hrs after operation, delayed time for rescue analgesia and decreased total need of analgesic in the first 24hrs post-operative compared to patients who received TAP nerves block. Conclusion IIN+IHN block was effective in reducing postoperative pain scores for 4-6 hours, lowering total 24-h postoperative opioid and analgesic consumption and delaying the need for rescue analgesia after inguinal hernia repair under general anesthesia, compared to TAP nerves block. It will be more useful to study in high-risk hypertensive and cardiac patients and to correlate with plasma catecholamine levels, which reflect the stress response and it is necessary to evaluate postoperative pain on movement in farther studies.

Abdominal wall muscle weakness outcomes after split abdominal flap repair of large congenital diaphragmatic hernias in newborn.

Split abdominal wall muscle flap (SAWMF) is a technique to repair large defects in congenital diaphragmatic hernia (CDH). A possible objection to this intervention could be any associated abdominal muscle weakness. Our aim is to analyze the evolution of this abdominal muscle wall weakness. Retrospective review of CDH repair by SAWMF (internal oblique muscle andtransverse) from 2004 to 2023 focusing on the evolution of muscle wall weakness. Eighteen neonates of 148 CDH patients (12,1%) were repaired using SAWMF. Mean gestational age and birth weight were 35.7 ± 3.5weeks and 2587 ± 816g. Mean lung-to-head ratio was 1.49 ± 0.28 and 78% liver-up. Seven patients (38%) were prenatally treated by tracheal occlusion. Ninety-four percent of the flaps were used for primary repair and one to repair a recurrence. One patient (5.6%) experienced recurrence. Abdominal muscle wall weakness was present in the form ofa bulge. Resolution of weakness at 1, 2 and 3years was 67%, 89% and 94%, respectively. No patient required treatment for weakness or died. Abdominal muscular weakness after a split abdominal wall muscle flap repair is not a limitation for its realization since it is asymptomatic and presents a prompt spontaneous resolution. IV.

Sport-Specific Abdominal Wall Muscle Differences: A Comparative Study of Soccer and Basketball Players Using Ultrasonography

Aim: This study aims to compare the thickness of abdominal wall muscles—the external oblique (EO), internal oblique (IO), transversus abdominis (TrAb), rectus abdominis (RA), and inter-recti distance (IRD)—between amateur soccer and basketball players using ultrasonography. Methods: This cross-sectional study was conducted with 35 male amateur athletes, including 17 soccer players and 18 basketball players. Ultrasonographic measurements of the EO, IO, TrAb, RA muscles, and IRD were taken while the muscles were in a relaxed state for all the participants in both sides. Results: Significant differences were found in the RA muscle thickness, with basketball players showing a greater mean thickness compared to soccer players. No significant differences were observed in the TrAb, IO, and EO muscles between the two groups. The IRD showed a trend towards larger separation in basketball players, though this was not statistically significant. Conclusions: This study highlights sport-specific adaptations in the RA muscle, likely due to the distinct physical demands of basketball and soccer. The findings underscore the importance of tailored training and rehabilitation programs that consider these morphological differences to enhance performance and reduce injury risks.

Evaluation of Abdominal Musculature Thickness, Pelvic Tilt, and Trunk Mobility in Women with Primary Dysmenorrhea: A Cross-Sectional Observational Study.

Background: This cross-sectional observational study aimed to investigate differences in abdominal musculature thickness, pelvic tilt, and trunk mobility between women with primary dysmenorrhea (PD) and a control group (CG). Methods: Participants included 44 women (22 with PD and 22 controls) aged over 18, nulliparous, and of reproductive age. Ultrasound imaging was used to measure the thickness of the transverse abdominis (TrA), internal oblique (IO), external oblique (EO), and rectus abdominis (RA) muscles at rest and during contraction. Additionally, anterior pelvic tilt was assessed using the Palpation Meter (PALM), and trunk flexion and extension were measured using an accelerometer (activForce2). Results: Significant differences (p < 0.05) were found in RA and EO muscle thickness, with lower values in the PD group compared to CG. However, there were no significant differences (p > 0.05) in TrA and IO muscle thickness, anterior pelvic tilt, or trunk mobility between groups. Conclusions: These findings contribute to understanding the musculoskeletal factors potentially involved in dysmenorrhea. Further research is needed to explore associations between PD and structural and alignment parameters.

Newly revealed anatomy of the bucinator muscle: An anatomical and histological study

BackgroundCurrent anatomical knowledge of the origin of the bucinator muscle (BM), i.e., long thin attachments on the maxilla and mandible and the pterygomandibular raphe (PMR), is not supported by anatomical dissection of this muscle. The aim of this study was therefore to investigate the detailed morphology of the BM and associated structures and to discuss its function. MethodsThe anatomy of the BM and related structures was investigated in 15 cadaveric heads using a surgical microscope and histological analysis. ResultsThe inferior fibers of the BM originated from a small retromolar area (internal oblique line), which shared a common tendon with the deep tendon of the temporalis. The superior fibers of the BM originated from the maxillary tuberosity. The middle fibers originated the pterygoid hamulus. No PMR was identified in any of the specimens, but the border between the BM and superior pharyngeal constrictor muscle (SC) was clear because the muscle fibers followed different directions. Some horizontal fibers were continuous between the BM and SC. ConclusionsOur results suggest the need to revise established accounts of the origins of the bucinator (the maxillary tuberosity, conjoint tendon of the temporalis, and pterygoid hamulus without a pterygomandibular raphe. It also needs to be noted that some of its fibers merge directly with the SC.

Gender Differences in Core Muscle Morphology of Elite Alpine Skiers: Insights from Ultrasonography.

A cross-sectional design was employed, examining ultrasound imaging (USI) in 22 elite skiers (11 male, 11 female) to assess the thickness of the external oblique (EO), internal oblique (IO), transversus abdominis (TrAb), and rectus abdominis (RA) muscles. Significant differences were noted, with male skiers displaying greater muscle thickness, particularly in the right IO and RA and left IO, EO, TrAb, and RA. These findings suggest that male and female skiers may require different training approaches to optimize performance and reduce injury risks. This research contributes to a deeper understanding of the physical demands on elite skiers and underscores the need for gender-specific training regimens to enhance athletic outcomes and prevent injuries.

The effects of various stair-climbing exercises on functional mobility and trunk muscle activation in community-dwelling older adults: A pilot randomized controlled trial.

Stair-climbing (SC) is an essential daily life skill, and stair-climbing exercise (SCE) serves as a valuable method for promoting physical activity in older adults. This study aimed to compare the impact of SCEs with heel contact (HC) and heel off (HO) during SC on functional mobility and trunk muscle (TM) activation amplitudes in community-dwelling older adults. In the pilot randomized controlled trial, participants were randomly allocated to either the HC group (n = 17; mean age 75.9 ± 6.3 years) or the HO group (n = 17; mean age 76.5 ± 4.6 years). The HC participants performed SCE with the heel of the ankle in contact with the ground, while the HO participants performed SCE with the heel of the ankle off the ground during SC. Both groups participated in progressive SCE for one hour per day, three days per week, over four consecutive weeks (totaling 12 sessions) at the community center. We measured timed stair-climbing (TSC), timed up and go (TUG), and electromyography (EMG) amplitudes of the TMs including rectus abdominis (RA), external oblique (EO), transverse abdominus and internal oblique abdominals (TrA-IO), and erector spinae (ES) during SC before and after the intervention. Both groups showed a significant improvement in TSC and TUG after the intervention (P < .01, respectively), with no significant difference between the groups. There was no significant difference in the EMG activity of the TMs between the groups after the intervention. The amplitude of TMs significantly decreased after the intervention in both groups (P < .01, respectively). Both SCE methods could improve balance and SC ability in older adults while reducing the recruitment of TMs during SC. Both SCE strategies are effective in improving functional mobility and promoting appropriate posture control during SC in older adults.

HERNIA MESH EXPLANTATION FOR MESH INGUINODYNIA AND ALLODYNIA. WHY IS HERNIA MESH SO PAINFUL?

Abstract Introduction Chronic pain after mesh repair for abdominal wall hernia is an indication for the removal of mesh and reconstruction by a non-mesh technique. Materials and Methods In a consecutive series over 19 years, 128 patients had mesh removed to relieve chronic pain. This open method of mesh removal relies on confirming normal anatomical landmarks. The superior and inferior leaf of the External oblique aponeurosis are raised, the spermatic cord is identified and retracted. The mesh is gently dissected off the Internal oblique from lateral to medial, taking care in preserving the vas, and accompanying vessels. Adherent ilio-inguinal, iliohypogastric and genitofemoral nerves are removed with the mesh. The resultant recurrent hernia is repaired by Moloney darn, a tension-free tissue repair. Results 128 consecutive patients have been treated by mesh explantation and immediate reconstruction on average 6 years after implantation. Resolution of symptoms was experienced very shortly after the mesh removed. Preperitoneal mesh particularly Kugel patch has been the most difficult to remove. Meshes have been submitted for histological examination and the findings are usually chronic granulomatous foreign body reaction. Few complications have been encountered with a follow-up period ranging from 6 months to 15 years, the most common being the failure of explantation to alleviate inguinal pain in the long-term. Conclusion All hernia patients should be afforded informed consent including discussing the potential long-term consequences of chronic groin and abdominal pain.

PATIENT CASE STUDY: REBUILDING A PATIENT’S LIFE NOT JUST THEIR ABDOMINAL WALL – EXPERIENCE FROM A TERTIARY HERNIA CENTRE ON THE IMPACT OF ABDOMINAL WALL RECONSTRUCTION ON QUALITY OF LIFE

Abstract Introduction Abdominal wall reconstruction is a transformative intervention, significantly improving the quality of life for individuals with complex defects. This paper focuses on sharing a patient's experience post-surgery. Case Presentation The patient presented with a complex incisional hernia following a laparotomy, Hartmann’s procedure and splenectomy for perforated diverticular disease. Their CT scan showed a 16.5 × 17.5 cm defect, with a separate component involving their colostomy and lateral displacement of their muscle complexes. The hernia significantly impacted the patient's quality of life, manifesting as daily moderate pain that hindered routine activities. They required daily dressings and antibiotics due to skin changes over the hernia. Furthermore, dissatisfaction with the cosmetic appearance of the hernia contributed to the overall burden on the patient. Management and Outcomes The patient underwent pre-operative botulinum toxin injections six weeks prior to their abdominal wall reconstruction. They received 200 units divided equally between internal and external obliques. During their surgery they required a left sided transversus abdominus release and an &amp;gt;5cm mesh overlap was achieved in all directions. A post-operative CT scan conducted ten days after the surgery revealed no complications. The patient's recovery progressed well, leading to their discharge 12 days post-surgery. Discussion The patient was reviewed nine months post-surgery. Expressing high satisfaction with the surgical outcome, they conveyed a profound positive impact on their quality of life. The patient's newfound confidence in the improved cosmesis of their hernia was evident. Overall, the surgery proved transformative, liberating the patient from the burdens of frequent medical appointments and instilling a renewed sense of self-assurance.

#360 Short-term treatment with medium cut-off dialyzers increases muscle mass with preserved fat tissue in maintenance HD patients

Abstract Background and Aims Protein-energy wasting is a significant complication of maintenance hemodialysis (HD) patients characterized by reduced fat or muscle mass and strength. The combination of non-modifiable general and disease-related factors, such as uremic toxin accumulation and systemic inflammation, is responsible for this condition. Medium cut-off (MCO) membranes are designed to provide clearance of large-middle molecular weight uremic toxins and inflammatory cytokines without causing loss of albumin. This study aimed to investigate the short-term effect of MCO dialyzers on fat tissues and muscle mass. Method We conducted a prospective, single-center cross-over study on maintenance HD patients treated with regular low-flux (LF) dialyzers. Fat tissues were measured with a skinfold caliper and mid-upper arm circumference. Muscle thickness and strength parameters from six different muscle groups were evaluated with ultrasound. The baseline (control) parameters were measured under LF dialyzers, and the measurements were repeated two weeks after switching to MCO dialyzers for the patients ordered by their clinicians according to the clinical indications. Results The median age was 69.5 (50.3,78.8) years, and 60% of the patients were female. Two weeks after switching to MCO, the Kt/Vs, urea reduction ratios, mean serum albumin, dry weight, and body mass index scores were similar. Mean skinfold thickness and mid-upper arm circumference were 15 mm (11,17) and 28mm (27,30) under LF and 16mm (14,19) and 28mm (27,30) under MCO dialyzers (p=0.82 and p=0.27). Rectus abdominis and external oblique muscle groups remained similar. Internal and external oblique muscle thickness were significantly increased (p=0.002 and p=0.001). Mean rectus femoris and gastrocnemius medialis (GKM) thicknesses were 1.19cm (0.99,1.33) and 1.16cm (0.9,1.4) under LF and 1.31cm (1.20, 1.40) and 1.24cm (0.95,1.40) under MCO dialyzers (p=0.002 and p=0.02). Mean GKM fibrile length and pennation angles were 2.4cm (2.2,2.8) and 20o (18,23) under LF and 2.7cm (2.4, 2.9) and 22o (19,24) under MCO dialyzers (p=0.007 and p=0.001). Conclusion Our study showed that MCO dialyzers increase muscle mass with preserved fat tissues in HD patients, short-term follow-up. This favorable effect might be due to the clearance of uremic toxins, which cannot be removed with conventional methods. If long-term studies support our findings, MCO dialyzers would be a milestone for the treatment of sarcopenia in HD patients.

Comparison of trunk muscle activity during lumbar stabilization exercises on stable and unstable surfaces.

Lumbar stabilization exercises (LSE) provide dynamic trunk stability, promote muscle strength and endurance, and improve low back pain rehabilitation and performance. To clarify the differences in trunk muscle activity during LSEs on stable and different unstable surfaces. Fifteen healthy males performed three exercises (elbow-toe, hand-knee, and side bridge) on stable (floor) and unstable surfaces. Muscle activity of the bilateral rectus abdominis, internal oblique, external oblique, and erector spinae were recorded. Data were compared using the Friedman test. Pairwise comparisons were performed using Wilcoxon's signed rank test if significant differences were observed. In the elbow-toe exercise, muscle activity of the rectus abdominis and right internal oblique increased in the following order: floor, low-difficulty, and high-difficulty unstable surface. In the hand-knee exercise, muscle activity of the internal oblique on the lower-extremity elevated side, external oblique, and erector spinae on the upper-extremity elevated side were greater on unstable surface exercise performance. In the side bridge exercise, rectus abdominis muscle activity was highest on a high-difficulty unstable surface. Trunk muscle activity increased during exercise on unstable surfaces. Since the effects of unstable surfaces vary depending on muscle and exercise types, exercise difficulty and surface stability must be considered accordingly.

Trunk muscle activation in prone plank exercises with different body tilts.

Body tilt changes could affect the intensity/difficulty of core stability exercises, but there is still a lack of knowledge about its impact. To analyse the trunk muscles activation during prone plank exercises at different body tilts. Twenty-four young adults who performed recreational gymnastic activities participated in this study. Electromyography activity of the rectus abdominis (RA), external oblique (EO), internal oblique (IO) and erector spinae (ES) was recorded during the performance of six variations of the prone plank exercise (planking with feet supported on the ground [conventional horizontal position] and planking with feet supported on wall bars at five different heights increasing the angle tilt) and an inverted position exercise. The RA, EO and IO activation in all prone plank variations were higher than those observed in the conventional prone plank. In addition, the coefficient of variation of the muscle activation increased with the declination angle, reaching the highest values in the inverted position for the RA and ES muscles. The results seem to indicate that the body tilt variation could be used as an easy and inexpensive strategy for modulating the neuromuscular demands and the motor control challenge during planking exercises.

Role of muscle ultrasound in frailty assessment in older adults with type 2 diabetes mellitus

BackgroundFrailty is a geriatric syndrome that is characterized by increased vulnerability to intrinsic and extrinsic stressors due to decreased biologic reserves. Muscle ultrasound (US) is a valid and reliable method for assessing muscle quantity in older adults. The study aims to examine the relationship between frailty definitions and US-derived muscle parameters.MethodsWe conducted a cross-sectional study with type 2 diabetes mellitus outpatients in a tertiary hospital, and all participants underwent a comprehensive geriatric assessment. For frailty assessment, the Fried Frailty Phenotype (FFP), the Clinical Frailty Scale (CFS), and the Edmonton Frailty Scale (EFS) were performed. Muscle US measurements included Gastrocnemius Medialis (GM) muscle thickness, GM fascicle length, GM pennation angle, Rectus Femoris (RF) muscle thickness, Rectus Femoris cross-sectional area (RFCSA), Rectus Abdominis (RA) muscle thickness, External Oblique (EO) muscle thickness, Internal Oblique (IO) muscle thickness, and Transverse Abdominis (TA) muscle thickness.ResultsIn all, 373 participants were included in the study. The median age of participants was 72.7 ± 5.9 years, and 64.6% of them were female. According to the FFP, 18.2% of the participants were living with frailty, 56% of them were pre-frail; 57.4% of them were living with frailty according to the CFS; 25.2% of them were living with frailty, and 20.6% of them were pre-frail according to the EFS. The FFP, CFS, and EFS scores were related to muscle thickness of GM, RF, and RA, fascicle length of GM, and pennation angle of GM and RFCSA. Particularly, GM pennation angle, RF muscle thickness, and RFCSA were associated with an increased risk of frailty. Besides muscle thickness of GM, RF, and RA, fascicle length of GM, pennation angle of GM, and RFCSA were significant for predicting the presence of frailty.ConclusionsUS-derived regional muscle measurements are associated with frailty definitions (in both physical, cumulative deficit, and multidimensional models) in a diabetic geriatric population.

A COMPARATIVE STUDY OF EFFECT OF DEXMEDETOMIDINE AND DEXAMETHASONE AS AN ADJUVANT TO 0.2% ROPIVACAINE FOR ULTRASOUND GUIDED TRANSVERSUS ABDOMINIS PLANE BLOCK FOR INFRAUMBILICAL SURGERIES

Background: The relief of pain and suffering is, and always has been, one of the primary concerns of mankind and one of the prime factors that has influenced the course of history of medicine. Transversus abdominis plane (TAP) block is a regional anaesthetic technique which blocks the abdominal neural afferents by introducing local anaesthetic into the neuro-fascial plane between the internal oblique and the transversus abdominis muscle. Aim: To compare the efficacy of Dexmedetomidine and dexamethasone as an adjuvant to 0.2%ropivacaine in ultrasound guided transverses abdominis plane block in infra umbilical surgeries in terms of, 1. Time to initial postoperative pain. 2. Time to initial rescue analgesia. 3. Quality of block.. 4. Total postop analgesic consumption. 5. Patient satisfaction with regard to pain relief. 6. Post-operative nausea and vomiting. Materials And Methods: We included 80 patients of age between 18-60 years of American Society of Anesthesiologists status (ASA)I and II scheduled for elective infraumbilical surgeries in our study. We randomly allotted these patients into two groups namely Group A and Group B of each. Patients in Group APatients who received transversus abdominis plane block with - 18ml Ropivacaine 0.2%+ 2 ml Dexamethasone 8mg. Patients in Group B received transversus abdominis plane block with-18ml Ropivacaine 0.2%+ 2 ml Dexmedetomidine .This TAP block was given soon after the surgery is completed. The duration of block and regression of sensory block, time for rescue analgesia, degree of sedation, hemodynamic parameters, post operative analgesia and adverse effects were noted. Result: The two groups were comparable on the basis of duration of surgery, site of surgery, ASA and BMI. Heart rates and mean arterial pressure were compared and it was found to be significantly lower in group B compared to group A until initial 5 hours. In our study we found that the visual analogue score at rest and on coughing between groups A and B was statistically insignificant. However, the time to first rescue analgesia (330 mins vs 240 mins) and total analgsic consumption in the 24 hours period post operatively was significantly lesser for group A compared to group B. Ramsey sedation score was significantly higher in group B compared to group A until 8 hourspost operatively. Nausea and vomiting in 3 cases of group A , and 2 cases in group B. No other significant side effects were noted. Conclusion: USG-guided TAP block is an effective and safe adjunct for postoperative analgesia in infra umblical surgeries. Addition of dexamethasone as an adjuvant prolongs the duration and reduces post-operative analgesic requirement in patients significantly more than dexmedetomidine whereas dexamethasone provides better control of the heart rate and mean arterial pressure.

Effects of abdominal hollowing and bracing on each intervertebral angle during quadruped upper and lower extremity lift: Three-dimensional motion analysis of the spine

To investigate the effects of intentionally minimizing spinal motion and abdominal muscle contractions on intervertebral angles during quadruped upper and lower extremity lift (QULEL). Fifteen healthy men performed the QULEL under four conditions: without any special instructions (basic), with the intention to minimize spinal motion (intentional), with abdominal bracing (bracing), and with abdominal hollowing (hollowing). Each intervertebral angle was calculated from the local coordinate system using the marker data obtained from a motion capture system. Shear moduli, as indicators of the activities of the right transversus abdominis (TrA), internal and external oblique, and rectus abdominis muscles, were assessed using shear wave elastography during QULEL. One-way repeated-measures analysis of variance and multiple comparisons among conditions were used to compare each shear modulus of the abdominal muscle and the changes in thoracic kyphosis (Th1-12), lumbar lordosis (L1-5), and lumbar intervertebral angles from the quadruped position to QULEL. The significance level was set at P < 0.05. Changes in lumbar lordosis and L2/L3 and L3/L4 extension angles were significantly lower under hollowing than under other conditions (effect size ηG2: lumbar lordosis, 0.068; L2/L3, 0.072; L3/L4, 0.043). The change in the L1/L2 extension angle significantly decreased in bracing and hollowing compared with the basic (ηG2 = 0.070). Only the TrA shear modulus significantly increased in bracing and hollowing compared with the basic (ηG2 = 0.146). Abdominal hollowing during the QULEL increased TrA activity and suppressed lumbar extension, except at L4/L5, and may be more effective as a rehabilitation exercise for controlling spinal motion.

What is the significance of trunk muscle morphology in terms of balance? Structure vs function in chronic post-stroke patients. A cross-sectional study

Objective: To assess the architecture of the trunk muscles with RUSI and to reveal which parameters may be related to balance assessment tools in patients that suffered a stroke with hemiparesis. Methods: An observational, analytical, cross-sectional, matched case-control study was conducted, nested within a single-center cohort comprising patients with chronic hemiparesis. Twenty individuals in the chronic post-stroke stage and twenty healthy controls were recruited for this investigation. Key outcomes included the thickness measurements of the Rectus Abdominis (RA), External Oblique (OE), Internal Oblique (OI), Transversus Abdominis (TrAb), and Lumbar Multifidus (LMult) muscles, as well as assessments using the Modified Rivermead Functional Test (MRFT), Timed Up and Go (TUG), and BERG scales. Results: Results did not show statistically significant differences between groups for the outcomes measured. Conclusions: The findings indicate no significant disparities between the measured sides, suggesting that muscle alterations in patients that suffered a stroke may be more pronounced during the acute stage compared to the chronic stage. Keywords: Stroke, trunk, balance.

Comparison of the Electromyography Activity during Exercises with Stable and Unstable Surfaces: A Systematic Review and Meta-Analysis.

The effect of electromyographic (EMG) activity on agonist muscles during exercises performed on stable and unstable surfaces remains uncertain. We aimed to review the literature regarding the comparison of the EMG activity of the agonist muscles of exercises performed on stable and unstable surfaces. Eighty-six studies that evaluated the EMG activity of 1783 individuals during exercises for the lower limbs, upper limbs, and core were included. The EMG activities of the pectoralis major (SMD = 0.28 [95% CI 0.09, 0.47]) and triceps brachii muscles (SMD = 0.45 [95% CI 0.25, 0.66]) were significantly increased when the unstable device was added to the exercise. Likewise, the EMG activity of all core muscles showed a significant increase with the unstable surface during the exercises, such as the rectus abdominis (SMD = 0.51 [95% CI 0.37, 0.66]), external oblique (SMD = 0.44 [95% CI 0.28, 0.61]), internal oblique (SMD = 1.04 [95% CI 0.02, 2.07]), erector spinae (SMD = 0.37 [95% CI 0.04, 0.71]), and lumbar multifidus (SMD = 0.35 [95% CI 0.08, 0.61]). However, the lower limb muscles did not show greater EMG activity during the exercise with unstable surfaces compared to the stable surface. In conclusion, unstable conditions increase the EMG activity of some upper limb and core muscles compared to a stable surface.

A Comparison between Core Stability Exercises and Muscle Thickness Using Two Different Activation Maneuvers.

Core stability training is crucial for competitive athletes, individuals who want to improve their health and physical performance, and those undergoing clinical rehabilitation. This study compared the ultrasound (US) muscle thickness of the abdominals and lumbar multifidus (LM) muscles between seven popular trunk stability exercises performed using hollowing and bracing maneuvers. Forty-four healthy young adults, aged between 21 and 32 years, performed a plank, bird dog, beast crawl, dead bug, Pilates tap, bridge, and side planks using the bracing and the hollowing maneuver. The thickness of the transversus abdominis (TrA), internal oblique (IO), and LM muscles was measured simultaneously using two ultrasound machines. Analysis of variance designs indicated that during hollowing, the bird dog and side plank exercises resulted in the greatest increase in the muscle's relative thickness overall. The relative thickness of all muscles was significantly greater (p < 0.001) during hollowing (22.7 ± 7.80 to 106 ± 24.5% of rest) compared to bracing (18.7 ± 7.40 to 87.1 ± 20.9% of rest). The TrA showed the greatest increase in thickness (p < 0.001) compared to the IO and LM. Additionally, the IO had a greater increase in thickness (p < 0.001) than the LM. In conclusion, our findings indicate that the bird dog and side plank exercises, when performed with hollowing, showed the most significant total muscle thickness increase. Notably, the hollowing maneuver enhances the thickness of the TrA, IO, and LM muscles more than the bracing maneuver. This contributes to the discussion on optimal strategies for dynamic core stabilization.

Effects of Ankle Position While Performing One- and Two-Leg Floor Bridging Exercises on Core and Lower Extremity Muscle Recruitment.

Given there are no known studies which have examined multiple lower extremity muscles between different ankle positions during bridging activities, the objective was to assess how employing two different ankle positions (PF versus DF) while performing five common bridging exercises (three bipedal and two unipedal) used in rehabilitation and athletic performance affect core and select lower extremity muscle EMG recruitment. Twenty healthy subjects performed a 5 s isometric hold during five two- and one-leg bridge exercises: (1) on right leg with left knee to chest (1LB-LFlex); (2) on right leg with left knee extended (1LB-LExt); (3) standard two-leg bridge (2LB); (4) two-leg bridge with resistance band around knees (2LB-ABD); and (5) two-leg bridge with ball between knees (2LB-ADD). Surface electromyographic (EMG) data were collected using a Noraxon Telemyo Direct Transmission System from fourteen muscles: (1) three superficial quadriceps (VM, VL, and RF); (2) three hip abductors (TFL, GMED, and GMAX); (3) medial hamstrings (ST) and lateral hamstrings (BF); (4) hip adductors (ADD); (5) erector spinae (ES); (6) latissimus dorsi (LATS); (7) upper rectus abdominis (RA); and (8) external oblique (EO) and internal oblique (IO). EMG data were normalized by maximum voluntary isometric contractions (MVICs). A paired t-test (p < 0.01) was used to assess differences in normalized mean EMG activities between DF and PF for each exercise. EMG activities were significantly greater in DF than PF for the (a) VM, VL, and RF during 1LB-LFlex; (b) ADD during 1LB-LFlex, 1LB-LExt; (c) EO during 1LB-LFlex; and (d) IO during 1LB-LFex. In contrast, EMG activities were significantly greater in PF than DF for ST and BF during all five bridge exercises. Bridging with PF (feet flat) was most effective in recruiting the hamstrings, while bridging with DF (feet up) was most effective in recruiting the quadriceps, hip adductors, and internal and external obliques.

Assessment of Lateral Abdominal Muscle Activation Asymmetry via M-mode Ultrasonography.

This study aimed to evaluate the asymmetry in the lateral abdominal muscles (LAMs) expressed as tissue deformation index asymmetry (aTDI) with the use of M-mode ultrasonography. The muscles of interest were the transversus abdominis, internal oblique, and external oblique. This is a cohort of 126 healthy subjects who participated in the study. Measurements were taken by two raters, blinded to the aim of the study. M-mode ultrasounds with a measurement frequency of 5 MHz were utilized to record the postural response of LAMs to external perturbation in the form of rapid arm abduction with load, and individual aTDI values for each muscle were calculated. The aTDI values from deep to superficial LAMs were 78.28% for transversus abdominis, 55.68% for internal oblique, and 44.80% for external oblique. Only the aTDI for transversus abdominis results differed significantly from those of the other LAMs (P<0.05). LAM asymmetry values exhibit the following gradient: transversus abdominis >internal oblique >external oblique. Specifically, only transversus abdominis demonstrates noteworthy asymmetry in postural activity. This observation contributes to the literature by indicating that transversus abdominis asymmetry may serve as a marker for assessing the variability in motor control of the deep abdominal musculature. The dominance of transversus abdominis (TrA) asymmetric activity underlines the importance of personalized approaches for patients with lumbopelvic disorders or for athletes seeking to enhance performance.