scholarly journals Assessment of a passive wearable robot for reducing low back disorders during rebar work

2021 ◽  
Vol 26 ◽  
pp. 936-952
Author(s):  
Nihar J. Gonsalves ◽  
Omobolanle R. Ogunseiju ◽  
Abiola A. Akanmu ◽  
Chukwuma A. Nnaji
Keyword(s):  
Task Performance ◽  
Latissimus Dorsi ◽  
Completion Time ◽  
Mixed Effects ◽  
Erector Spinae ◽  
Low Back ◽  
Body Parts ◽  
Wearable Robot ◽  
Back Disorder ◽  
Muscle Activations

Low back disorder continues to be prevalent amongst construction workers, especially the rebar workers who are often engaged in repetitive stooping postures. Wearable robots, exoskeletons, are recent ergonomic interventions currently explored in the construction industry that have potentials of reducing the risks of low back pain by augmenting users’ body parts and reducing demands on the back. This paper presents the assessment of a commercially available passive wearable robot, BackX, designed for reducing low back disorder amongst rebar workers. The study evaluated the exoskeleton in terms of task performance and physiological conditions. Outcome measures such as completion time were employed to evaluate the effect of the exoskeleton on task performance, while activations of Erector Spinae and Latissimus Dorsi muscles, and perceived discomfort across body parts were employed to assess the physiological effects of the exoskeleton. The results indicated mixed effects of the exoskeleton on muscle activations. Although the results revealed that the exoskeleton can reduce muscle activations across the Latissimus Dorsi, mixed effects were observed for the Erector Spinae especially during the forward bending tasks. The exoskeleton reduced completion time by 50% during the rebar tasks. There was also a 100% reduction in perceived discomfort on the back, but discomfort was tripled at the chest region when the exoskeleton was worn. This study reveals the potentials of the exoskeleton for reducing low back disorder and improving productivity amongst the rebar workers. However, the unintended consequences such as increased discomfort at the chest region and activations of the muscles highlight the need for improving existing exoskeleton designs for construction work.

Ergonomic Analysis of Pallets and Drum Handling

2002 ◽  
Vol 46 (13) ◽  
pp. 1157-1161
Author(s):  
Bernard Martin ◽  
Diane Adamo ◽  
Robert Felicitas ◽  
Stephen Burastero ◽  
K. Han Kim
Keyword(s):  
Lawrence Livermore National Laboratory ◽  
National Laboratory ◽  
Erector Spinae ◽  
Electromyographic Activity ◽  
Low Back ◽  
Back Muscle ◽  
Back Disorder ◽  
Disc Compression ◽  
Ergonomic Analysis ◽  
Waste Drums

This study investigates the effects of heavy pallet and drum handling on spinal loading at the L5/S1 region and surface electromyographic activity of the erector spinae muscles, and the associated risk of low back disorder (LBD). Ten field technicians at the Lawrence Livermore National Laboratory (LLNL) were asked to unstack plastic and metallic pallets and manipulate 55 gallon waste drums. Lifting the metallic and plastic pallets and lowering a 34 Kg drum induced the highest disc compression at the L5/S1 level, while manipulating the pallets and breaking up a 203 Kg drum induced the highest low back muscle activity. The major results showed that posture has a significant influence on disc compression force; however, the lowest muscle load may not be correlated with the lowest disc compression. The computed disc compression forces and EMG activities are most likely responsible for the elevated risk of back injury in waste management workers.

Biomechanical and Electromyographic Comparisons of Isometric Trunk Flexor Endurance Test Postures: Prone Plank Versus V-Sit

2015 ◽  
Vol 31 (6) ◽  
pp. 469-475
Author(s):  
Lindsay L. Musalem ◽  
Tatjana Stankovic ◽  
Drazen Glisic ◽  
Gillian E. Cook ◽  
Tyson A.C. Beach
Keyword(s):  
Lumbar Spine ◽  
Latissimus Dorsi ◽  
Body Position ◽  
Reaction Force ◽  
Rectus Abdominis ◽  
Erector Spinae ◽  
Endurance Capacity ◽  
Low Back ◽  
Endurance Test ◽  
Force Data

The objective of this study was to investigate why holding times on 2 different tests of isometric trunk flexor endurance capacity (prone plank and v-sit) are weakly correlated. Body position and ground reaction force data from 10 men and 10 women were used to conduct static biomechanical analyses of both test postures, and bilateral activations of the rectus abdominis, internal and external obliques, latissimus dorsi, and lumbar and thoracic erector spinae were measured in a second sample of 15 men and 15 women while holding the test postures. No between-posture differences in net low back flexor moments were found (P = .111), but the lumbar spine was 28° more flexed in the v-sit than in the plank (P < .001). No between-posture differences were detected in the rectus abdominis (P = .397), external obliques (P = .204), internal obliques (P = .226), or lumbar erector spinae (P = .116) activation levels, but those of the thoracic erector spinae (P = .0253) and latissimus dorsi (P < .001) were greater in the plank than in the v-sit. Altogether, the findings suggest that differences between plank and v-sit holding times are most likely related to between-test differences in lumbar spine postures and shoulder demands.

scholarly journals Development of a trunk motor paradigm for use in neuroimaging

2020 ◽  
Vol 11 (1) ◽  
pp. 193-200
Author(s):  
Elizabeth Saunders ◽  
Brian C. Clark ◽  
Leatha A. Clark ◽  
Dustin R. Grooms
Keyword(s):  
Motor Control ◽  
Maximum Voluntary Contraction ◽  
Voluntary Contraction ◽  
Erector Spinae ◽  
Head Motion ◽  
Low Back ◽  
Cyclic Contraction ◽  
Cyclic Contractions ◽  
Measurement Units ◽  
Healthy Participants

AbstractThe purpose of this study was to quantify head motion between isometric erector spinae (ES) contraction strategies, paradigms, and intensities in the development of a neuroimaging protocol for the study of neural activity associated with trunk motor control in individuals with low back pain. Ten healthy participants completed two contraction strategies; (1) a supine upper spine (US) press and (2) a supine lower extremity (LE) press. Each contraction strategy was performed at electromyographic (EMG) contraction intensities of 30, 40, 50, and 60% of an individually determined maximum voluntary contraction (MVC) (±10% range for each respective intensity) with real-time, EMG biofeedback. A cyclic contraction paradigm was performed at 30% of MVC with US and LE contraction strategies. Inertial measurement units (IMUs) quantified head motion to determine the viability of each paradigm for neuroimaging. US vs LE hold contractions induced no differences in head motion. Hold contractions elicited significantly less head motion relative to cyclic contractions. Contraction intensity increased head motion in a linear fashion with 30% MVC having the least head motion and 60% the highest. The LE hold contraction strategy, below 50% MVC, was found to be the most viable trunk motor control neuroimaging paradigm.

Torso kinematics and low back disorder risk as a function of pallet orientation

2005 ◽  
Vol 4 (3) ◽  
pp. 173-183
Author(s):  
Michael J. Jorgensen ◽  
Amit Handa ◽  
Prabaharan Veluswamy
Keyword(s):  
Low Back ◽  
Back Disorder ◽  
Disorder Risk

The objective of this study was to assess the affect of pallet location on torso kinematics during lifting. Participants transferred 11.3 kg boxes to pallets at two orientations and two distances from a constant lift origin. When reorienting the pallet from 180° to 90°, torso twist, lateral and sagittal torso kinematics increased when palletizing to various locations on the pallet when keeping the pallet distance far. Torso flexion increased slightly at the lowest level on the pallet independent of the pallet distance. When keeping the pallet distance close, torso twist kinematics decreased only when palletizing to the highest and closest position of the pallet. When reorienting the pallet from 180° to 90° adjacent to the lift origin, the best strategy to reduce torso kinematics appears to be to eliminate the transferring of loads to the lowest level of the pallet, and keeping the pallet close to the lift origin.

Post-Render Warp with Late Input Sampling Improves Aiming Under High Latency Conditions

2020 ◽  
Vol 3 (2) ◽  
pp. 1-18
Author(s):  
Joohwan Kim ◽  
Pyarelal Knowles ◽  
Josef Spjut ◽  
Ben Boudaoud ◽  
Morgan Mcguire
Keyword(s):  
Task Performance ◽  
Completion Time ◽  
Source Code ◽  
Experimental Methodology ◽  
Task Completion ◽  
Controlled Environment ◽  
Content Creation ◽  
Remote Rendering ◽  
Streaming Services ◽  
Robotic Teleoperation

End-to-end latency in remote-rendering systems can reduce user task performance. This notably includes aiming tasks on game streaming services, which are presently below the standards of competitive first-person desktop gaming. We evaluate the latency-induced penalty on task completion time in a controlled environment and show that it can be significantly mitigated by adopting and modifying image and simulation-warping techniques from virtual reality, eliminating up to 80% of the penalty from 80 ms of added latency. This has potential to enable remote rendering for esports and increase the effectiveness of remote-rendered content creation and robotic teleoperation. We provide full experimental methodology, analysis, implementation details, and source code.

scholarly journals Rowers with a recent history of low back pain engage different regions of the lumbar erector spinae during rowing

2019 ◽  
Vol 22 (11) ◽  
pp. 1206-1212 ◽  
Author(s):  
Eduardo Martinez-Valdes ◽  
Fiona Wilson ◽  
Neil Fleming ◽  
Sarah-Jane McDonnell ◽  
Alex Horgan ◽  
...  
Keyword(s):  
Low Back Pain ◽  
Back Pain ◽  
Erector Spinae ◽  
Recent History ◽  
Low Back ◽  
History Of

The effect of pallet distance on torso kinematics and low back disorder risk

Ergonomics ◽  
2005 ◽  
Vol 48 (8) ◽  
pp. 949-963 ◽  
Author(s):  
Michael J Jorgensen ◽  
Amit Handa ◽  
Prabaharan Veluswamy ◽  
Manish Bhatt
Keyword(s):  
Low Back ◽  
Back Disorder ◽  
Disorder Risk

Use of Kinetic and Kinematic Data to Evaluate Load Transfer as a Mechanism for Flexion Relaxation in the Lumbar Spine

2013 ◽  
Vol 135 (10) ◽  
Author(s):  
Samuel J. Howarth ◽  
Paul Mastragostino
Keyword(s):  
Lumbar Spine ◽  
Body Mass ◽  
Full Range ◽  
Added Mass ◽  
Erector Spinae ◽  
Lower Limbs ◽  
Upper Body ◽  
Low Back ◽  
Kinematic Data ◽  
Flexion Relaxation

Flexion relaxation (FR) in the low back occurs when load is transferred from the spine's extensor musculature to its passive structures. This study investigated the influence of added upper body mass on low back kinetics and kinematics at the FR onset. Sixteen participants (eight male, eight female) performed standing full forward spine flexion with 0%, 15%, and 30% of their estimated upper body mass added to their shoulders. Electromyographic data were obtained from the lumbar erector spinae. Ground reaction forces and kinematic data from the lower limbs, pelvis, and spine were recorded. Extensor reaction moments (determined using a bottom-up linked segment model) and flexion angles at the FR onset were documented along with the maximum spine flexion. The angle at the FR onset increased significantly with added mass (p < 0.05). Expressing the FR onset angle as a percent of the full range of trunk flexion motion for that condition negated any differences between the added mass conditions. These findings demonstrate that low back kinetics play a role in mediating FR in the lumbar spine.

scholarly journals Alteration in HDEMG Spatial Parameters of Trunk Muscle Due to Handle Design during Pushing

Sensors ◽  
2021 ◽  
Vol 21 (19) ◽  
pp. 6646
Author(s):  
Jacqueline Toner ◽  
Jeremy Rickards ◽  
Kenneth Seaman ◽  
Usha Kuruganti
Keyword(s):  
Muscle Activity ◽  
Muscle Activation ◽  
Trunk Muscle ◽  
Erector Spinae ◽  
Low Back ◽  
Horizontal Orientation ◽  
Low Back Injuries ◽  
Spatial Parameters ◽  
Left And Right ◽  
Pushing And Pulling

Previous research identifies that pushing and pulling is responsible for approximately 9–18% of all low back injuries. Additionally, the handle design of a cart being pushed can dramatically alter a worker’s capacity to push (≅9.5%). Surprisingly little research has examined muscle activation of the low back and its role in muscle function. Therefore, the purpose of this study was to examine the effects of handle design combination of pushing a platform truck cart on trunk muscle activity. Twenty participants (10 males and 10 females, mean age = 24.3 ± 4.3 years) pushed 475 lbs using six different handle combinations involving handle orientation (vertical/horizontal/semi-pronated) and handle height (hip/shoulder). Multichannel high-density EMG (HDsEMG) was recorded for left and right rectus abdominis, erector spinae, and external obliques. Pushing at hip height with a horizontal handle orientation design (HH) resulted in significantly less (p < 0.05) muscle activity compared to the majority of other handle designs, as well as a significantly higher entropy than the shoulder handle height involving either the semi-pronated (p = 0.023) or vertical handle orientation (p = 0.028). The current research suggests that the combination of a hip height and horizontal orientation handle design may require increased muscle demand of the trunk and alter the overall muscle heterogeneity and pattern of the muscle activity.

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