INVESTIGATION ON A DEVELOPED WEARABLE ASSISTIVE DEVICE (WAD) IN REDUCTION LUMBAR MUSCLES ACTIVITY

A new wearable assistive device (WAD) was developed to decrease required force on the lumbar spine in static holding tasks. In order to obtain moments on lumbar spine in two conditions, with and without WAD, a biomechanical static model was used for estimation of external moments on lumbar spine. The results of biomechanical models indicated that there was a reduction in the lumbar moment ranging from 20% to 43% using WAD depending on the load and flexion angle. A total of 15 male healthy subjects were tested to experimentally verify the predicted reduction of external moments on the spine by wearing WAD. Normalized electromyography (EMG) of the right and left lumbar and thoracic erector spinae (LES, TES), latissimus dorsi (LD), external oblique (EO), internal oblique (IO) and rectus abdominus (RA) muscles were monitored at three lumbar flexion positions (0°, 30° and 60°) in symmetric posture with three different loads (0, 5 and 15 kg) in two conditions of with and without WAD. The effects of WAD and load were significant for all muscles but the interaction effects were only significant for extensor muscles groups (p < 0.016). Results of statistical analysis (ANOVA) on the normalized EMG while wearing WAD indicated that the muscle activity of right and left LES, TES and LD muscles significantly decreased (p < 0.001). This reduction for right LES, TES, LD muscles at 15 kg load and 60° trunk flexion were 23.2%, 30% and 27.8%, respectively which were in good agreement with the biomechanical model results.

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Abdominal Muscles Dominate Contributions to Vertebral Joint Stiffness during the Push-up

Journal of Applied Biomechanics ◽

10.1123/jab.24.2.130 ◽

2008 ◽

Vol 24 (2) ◽

pp. 130-139 ◽

Cited By ~ 9

Author(s):

Samuel J. Howarth ◽

Tyson A.C. Beach ◽

Jack P. Callaghan

Keyword(s):

Lumbar Spine ◽

Rectus Abdominis ◽

Erector Spinae ◽

Abdominal Muscles ◽

Rotational Stiffness ◽

Flexion Extension ◽

External Oblique ◽

Axial Twist ◽

Internal Oblique ◽

Push Up

The goal of this study was to quantify the relative contributions of each muscle group surrounding the spine to vertebral joint rotational stiffness (VJRS) during the push-up exercise. Upper-body kinematics, three-dimensional hand forces and lumbar spine postures, and 14 channels (bilaterally from rectus abdominis, external oblique, internal oblique, latissimus dorsi, thoracic erector spinae, lumbar erector spinae, and multifidus) of trunk electromyographic (EMG) activity were collected from 11 males and used as inputs to a biomechanical model that determined the individual contributions of 10 muscle groups surrounding the lumbar spine to VJRS at five lumbar vertebral joints (L1-L2 to L5-S1). On average, the abdominal muscles contributed 64.32 ± 8.50%, 86.55 ± 1.13%, and 83.84 ± 1.95% to VJRS about the flexion/extension, lateral bend, and axial twist axes, respectively. Rectus abdominis contributed 43.16 ± 3.44% to VJRS about the flexion/extension axis at each lumbar joint, and external oblique and internal oblique, respectively contributed 52.61 ± 7.73% and 62.13 ± 8.71% to VJRS about the lateral bend and axial twist axes, respectively, at all lumbar joints with the exception of L5-S1. Owing to changes in moment arm length, the external oblique and internal oblique, respectively contributed 55.89% and 50.01% to VJRS about the axial twist and lateral bend axes at L5-S1. Transversus abdominis, multifidus, and the spine extensors contributed minimally to VJRS during the push-up exercise. The push-up challenges the abdominal musculature to maintain VJRS. The orientation of the abdominal muscles suggests that each muscle primarily controls the rotational stiffness about a single axis.

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Effective erector spinae plane block for postoperative analgesia in a pyothorax patient who underwent emergency re-open thoracotomy—a case report

Ain-Shams Journal of Anesthesiology ◽

10.1186/s42077-019-0044-8 ◽

2019 ◽

Vol 11 (1) ◽

Author(s):

Izumi Kawagoe ◽

Daizoh Satoh ◽

Mariko Fukui ◽

Kenji Suzuki ◽

Eiichi Inada

Keyword(s):

Postoperative Analgesia ◽

Transverse Process ◽

Erector Spinae ◽

Open Thoracotomy ◽

Case Presentation ◽

Lung Lobectomy ◽

Erector Spinae Plane Block ◽

Lower Lung ◽

The Right ◽

Vein Stenosis

Abstract Background The appropriate choice of postoperative analgesia for pyothorax surgery is unclear since local infection could contaminate the catheter used for regional blocks and bacteremia can lead to disordered coagulation. We performed erector spinae plane block (ESPB) in a pyothorax patient undergoing emergency re-open thoracotomy. Case presentation An 81-year-old male with internal jugular vein stenosis on aspirin therapy was scheduled for pyothorax drainage and residual middle lobectomy 14 days after he underwent open right lower lung lobectomy for lung cancer. ESPB was performed with injection of 20 ml of 0.375% levobupivacaine at the Th5 transverse process of the right side under ultrasound guidance. Although he needed intravenous pentazocine for pain on postoperative day 0, no more analgesics were required postoperatively. NRS score ranged from 0 to 1 thereafter. Conclusions ESPB provided effective postoperative analgesia following emergency re-open thoracotomy for our pyothorax patient. ESPB might be the appropriate choice for postoperative analgesia following pyothorax surgery.

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Preoperative Fluoroscopically Guided Regional Erector Spinae Plane Blocks Reduce Opioid Use, Increase Mobilization, and Reduce Length of Stay Following Lumbar Spine Fusion

Global Spine Journal ◽

10.1177/21925682211010740 ◽

2021 ◽

pp. 219256822110107

Author(s):

Robert J. Owen ◽

Noah Quinlan ◽

Addisyn Poduska ◽

William Ryan Spiker ◽

Nicholas T. Spina ◽

...

Keyword(s):

Lumbar Spine ◽

Length Of Stay ◽

Lumbar Fusion ◽

Spine Fusion ◽

Erector Spinae ◽

Control Group ◽

Block Group ◽

Opioid Use ◽

Lumbar Spine Fusion ◽

Delivery Technique

Study Design: Retrospective review. Objective: To determine the effectiveness of erector spinae plane (ESP) blocks at improving perioperative pain control and function following lumbar spine fusions. Methods: A retrospective analysis was performed on patients undergoing < 3 level posterolateral lumbar fusions. Data was stratified into a control group and a block group. We collected postop MED (morphine equivalent dosages), physical therapy ambulation, and length of stay. PROMIS pain interference (PI) and physical function (PF) scores, ODI, and VAS were collected preop and at the first postop visit. Chi-square and student’s t-test ( P = .05) were used for analysis. We also validated a novel fluoroscopic technique for ESP block delivery. Results: There were 37 in the block group and 39 in the control group. There was no difference in preoperative opioid use ( P = .22). On postop day 1, MED was reduced in the block group (32 vs 51, P < .05), and more patients in the block group did not utilize any opioids (22% vs 5%, P < .05). The block group ambulated further on postop day 1 (312 ft vs 204 ft, P < .05), and had reduced length of stay (2.4 vs 3.2 days, P < .05). The block group showed better PROMIS PI scores postoperatively (58 vs 63, P < .05). The novel delivery technique was validated and successful in targeting the correct level and plane. Conclusions: ESP blocks significantly reduced postop opioid use following lumbar fusion. Block patients ambulated further with PT, had reduced length of stay, and had improved PROMIS PI postoperatively. Validation of the block demonstrated the effectiveness of a novel fluoroscopic delivery technique. ESP blocks represent an underutilized method of reducing opioid consumption, improving postoperative mobilization and reducing length of stay following lumbar spine fusion.

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Reduced biomechanical models for precision-cut lung-slice stretching experiments

Journal of Mathematical Biology ◽

10.1007/s00285-021-01578-2 ◽

2021 ◽

Vol 82 (5) ◽

Author(s):

Hannah J. Pybus ◽

Amanda L. Tatler ◽

Lowell T. Edgar ◽

Reuben D. O’Dea ◽

Bindi S. Brook

Keyword(s):

Smooth Muscle ◽

Muscle Contraction ◽

Ex Vivo ◽

Finite Thickness ◽

Biomechanical Model ◽

Local Stress ◽

Smooth Muscle Contraction ◽

Biomechanical Models ◽

Cytokine Activation ◽

Asymptotic Reduction

AbstractPrecision-cut lung-slices (PCLS), in which viable airways embedded within lung parenchyma are stretched or induced to contract, are a widely used ex vivo assay to investigate bronchoconstriction and, more recently, mechanical activation of pro-remodelling cytokines in asthmatic airways. We develop a nonlinear fibre-reinforced biomechanical model accounting for smooth muscle contraction and extracellular matrix strain-stiffening. Through numerical simulation, we describe the stresses and contractile responses of an airway within a PCLS of finite thickness, exposing the importance of smooth muscle contraction on the local stress state within the airway. We then consider two simplifying limits of the model (a membrane representation and an asymptotic reduction in the thin-PCLS-limit), that permit analytical progress. Comparison against numerical solution of the full problem shows that the asymptotic reduction successfully captures the key elements of the full model behaviour. The more tractable reduced model that we develop is suitable to be employed in investigations to elucidate the time-dependent feedback mechanisms linking airway mechanics and cytokine activation in asthma.

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Comparison among low intensity bridge exercises using suspension devices based on muscle activity and subjective difficulty

Journal of Back and Musculoskeletal Rehabilitation ◽

10.3233/bmr-200057 ◽

2021 ◽

pp. 1-6

Author(s):

Sang-Yeol Lee ◽

Se-Yeon Park

Keyword(s):

Inclination Angle ◽

Muscle Activity ◽

Erector Spinae ◽

Trunk Muscles ◽

Oblique Muscle ◽

Abdominal Muscles ◽

Internal Oblique Muscle ◽

Low Intensity ◽

Erector Spinae Muscle ◽

Internal Oblique

BACKGROUND: Recent clinical studies have revealed the advantages of using suspension devices. Although the supine, lateral, and forward leaning bridge exercises are low-intensity exercises with suspension devices, there is a lack of studies directly comparing exercise progression by measuring muscular activity and subjective difficulty. OBJECTIVE: To identify how the variations in the bridge exercise affects trunk muscle activity, the present study investigated changes in neuromuscular activation during low-intensity bridge exercises. We furthermore explored whether the height of the suspension point affects muscle activation and subjective difficulty. METHODS: Nineteen asymptomatic male participants were included. Three bridge exercise positions, supine bridge (SB), lateral bridge (LB), forward leaning (FL), and two exercise angles (15 and 30 degrees) were administered, thereby comparing six bridge exercise conditions with suspension devices. Surface electromyography and subjective difficulty data were collected. RESULTS: The rectus abdominis activity was significantly higher with the LB and FL exercises compared with the SB exercise (p< 0.05). The erector spinae muscle activity was significantly higher with the SB and LB exercises, compared with the FL exercise (p< 0.05). The LB exercise significantly increased the internal oblique muscle activity, compared with other exercise variations (p< 0.05). The inclination angle of the exercise only affected the internal oblique muscle and subjective difficulty, which were significantly higher at 30 degrees compared with 15 degrees (p< 0.05). CONCLUSIONS: Relatively higher inclination angle was not effective in overall activation of the trunk muscles; however, different bridge-type exercises could selectively activate the trunk muscles. The LB and SB exercises could be good options for stimulating the internal oblique abdominis, and the erector spinae muscle, while the FL exercise could minimize the erector spinae activity and activate the abdominal muscles.

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Using a Back Exoskeleton During Industrial and Functional Tasks—Effects on Muscle Activity, Posture, Performance, Usability, and Wearer Discomfort in a Laboratory Trial

Human Factors The Journal of the Human Factors and Ergonomics Society ◽

10.1177/00187208211007267 ◽

2021 ◽

pp. 001872082110072

Author(s):

Tessy Luger ◽

Mona Bär ◽

Robert Seibt ◽

Monika A. Rieger ◽

Benjamin Steinhilber

Keyword(s):

Heart Rate ◽

Muscle Activity ◽

Vastus Lateralis ◽

Erector Spinae ◽

Stair Climbing ◽

Trunk Flexion ◽

User Friendliness ◽

Timed Up And Go ◽

System Usability Scale ◽

Task Accomplishment

Objective To investigate the effect of using a passive back-support exoskeleton (Laevo V2.56) on muscle activity, posture, heart rate, performance, usability, and wearer comfort during a course of three industrial tasks (COU; exoskeleton worn, turned-on), stair climbing test (SCT; exoskeleton worn, turned-off), timed-up-and-go test (TUG; exoskeleton worn, turned-off) compared to no exoskeleton. Background Back-support exoskeletons have the potential to reduce work-related physical demands. Methods Thirty-six men participated. Activity of erector spinae (ES), biceps femoris (BF), rectus abdominis (RA), vastus lateralis (VL), gastrocnemius medialis (GM), trapezius descendens (TD) was recorded by electromyography; posture by trunk, hip, knee flexion angles; heart rate by electrocardiography; performance by time-to-task accomplishment (s) and perceived task difficulty (100-mm visual analogue scale; VAS); usability by the System Usability Scale (SUS) and all items belonging to domains skepticism and user-friendliness of the Technology Usage Inventory; wearer comfort by the 100-mm VAS. Results During parts of COU, using the exoskeleton decreased ES and BF activity and trunk flexion, and increased RA, GM, and TD activity, knee and hip flexion. Wearing the exoskeleton increased time-to-task accomplishment of SCT, TUG, and COU and perceived difficulty of SCT and TUG. Average SUS was 75.4, skepticism 11.5/28.0, user-friendliness 18.0/21.0, wearer comfort 31.1 mm. Conclusion Using the exoskeleton modified muscle activity and posture depending on the task applied, slightly impaired performance, and was evaluated mildly uncomfortable. Application These outcomes require investigating the effects of this passive back-supporting exoskeleton in longitudinal studies with longer operating times, providing better insights for guiding their application in real work settings.

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Hodgkin lymphoma presenting as alcohol-induced back pain

BMJ Case Reports ◽

10.1136/bcr-2018-228440 ◽

2019 ◽

Vol 12 (11) ◽

pp. e228440

Author(s):

Lucy Ma ◽

Sanskriti Varma ◽

Ashwini Niranjan-Azadi

Keyword(s):

Back Pain ◽

Lumbar Spine ◽

Hodgkin Lymphoma ◽

Anterior Chest Wall ◽

Marrow Transplant ◽

Radiographic Evaluation ◽

Anterior Mediastinal Mass ◽

Left Lower Extremity ◽

Stage Ivb ◽

The Right

A 32-year-old Chinese man without significant medical history presented with a 2-month history of worsening lumbosacral back pain radiating to the groin and left lower extremity. He also described a shooting pain in the sciatic nerve distribution that began with and was exacerbated by alcohol consumption, a rare but known symptom of Hodgkin lymphoma (HL). On exam, an anterior chest wall mass was noted. Radiographic evaluation of an anterior mediastinal mass showed osseous erosion into the manubrium. MRI of the lumbar spine showed diffuse osseous disease of the lower thoracic and lumbar spine with extension into the right sacroiliac joint and S2 neural foramen without vertebral body collapse or stenosis. Tissue biopsy revealed nodular sclerosis HL, stage IVB IPS2. The patient was primary refractory to ABVD (adriamycin, bleomycin, vinblastine, dacarbazine) therapy. Salvage ICE (ifosfamide, carboplatin, etoposide) chemotherapy was used and then followed by non-myeloablative haploidentical bone marrow transplant was performed on 5 March 2019.

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