Showing 5 results for Lifting
Naeimeh Asadi, Alireza Choobineh, Sareh Keshavarzi, Hadi Daneshmandi,
Volume 2, Issue 4 (3-2015)
Abstract
Introduction: Manual load lifting is the most common and most
stressful activity in manual handling of loads that imposes the highest
possible amount of biomechanical pressure on the body, particularly on the
spine. The present study was conducted to determine the prevalence of
musculoskeletal disorders and to estimate the mechanical force exerted on the
lower back in workers responsible for manual load lifting.
Material and Methods: The present
cross-sectional study was conducted on 120 workers responsible for manual load
lifting activities in 7 industrial settings in the city of Shiraz. The Nordic Musculoskeletal
Questionnaire (NMQ) was used for determining the prevalence of musculoskeletal
disorders and the 3DSSPP software was used to estimate the forces exerted on
the lower back during load lifting. Data were then analyzed in
SPSS-19.Findings: The results showed that lower back problems constitute the
most prevalent musculoskeletal disorder (68.3%). Evaluations conducted in
3DSSPP showed that in 17.5% of the cases, compressive forces, and in 10.8% of the
cases, shearing forces exerted on the L5-S1 disc were higher in the workers
than the permissible levels. There were no significant differences between the
rate of the prevalence of lower back pain at different levels of compressive
and shearing forces exerted on the disc (p>0/05).
Results: This finding might indicate the limitations of the
method used in this study for conducting a comprehensive assessment of loads
exerted on the spine.
Conclusion: The prevalence of musculoskeletal disorders, in particular
lower back pain, was estimated to be high among the subjects studied. The risk
levels of compressive and shearing forces exceeded the permissible amount in a
low percentage of the workers studied. The 3DSSPP software might have certain
limitations in the assessment of the pressure exerted on the spine.
Raziyeh Morshedi, Matreh Boazar, Davood Afshari, Kambiz Ahmadi Angali, Maryam Malek Zadeh,
Volume 3, Issue 1 (6-2015)
Abstract
Introduction: Manual handling of loads and carrying tasks widely exists in many occupations. Hospital staff because of Manual carrying of loads, are at increased risk of musculoskeletal disorders. Incorrect lifting methods, is an important risk factor for low back pain. The aim of this study was to analyze the biomechanical loads on the lumbar of nurses-aid in manual handling activities of serum cartons 12.5 kg in hospital and provide ergonomic solutions is the prevention of back pain.
Methods: This study was conducted one of the hospitals in Ahvaz city in year 1392. evaluated Postures were sampled through observation and photography. Then load lifting of complex index, was calculated by NIOSH equation and estimate the compressive forces on vertebras L5/ S1 as a quantitative index using software 3 D SSPP, during 2 stages before and after the intervention. The results of tests using Correlation, Regression and T-test were analyzed
Results: The results showed that the highest RWL in the top row 89/9 kg and minimum on the bottom row was 44/5 kg. The highest and lowest compressive force was estimated in the bottom and top rows, respectively, 6727 and 3707 Newton. Results of statistical tests showed significant reduction between the load lifting of complex index(CLI), and the compressive force average before and after the reform is the work station.
Conclusion:Throgh biomechanical analysis of work stations with two methods quantitatively and qualitatively can be made more accurate assessment and ergonomic conditions at work stations can be modified more accurately.
Seyed Sajad Ataei, Payam Heydari, Sakineh Varmazyar,
Volume 4, Issue 4 (3-2017)
Abstract
Introduction: Heavy load lifting or occupational and individual factors are effective hazard agents in the occurrence of musculoskeletal disorders. Therefore, the aim of the present study was investigating the correlation of musculoskeletal disorders with work ability index and allowable load lifting limit.
Methods: This analytical and cross-sectional study was conducted using census (n = 60) among the kitchen workers in Qazvin teaching hospitals in 2016. Data were collected through questionnaires including pain prevalence, work ability index and allowable load lifting limit. Data was analyzed by single and multiple regression logistic using SPSS 16 software.
Results: The highest prevalence was observed in the lower back (78.3%). Of the workers, 61.7% reported a good level of work ability index and 58.3% of the workplaces were in unsafe conditions of load handling. Unsafe condition alone increased the prevalence of shoulder and neck pain about 7 times and the lower back pain 4 times, and in interaction with other risk factors, the prevalence of neck and shoulder pains had 25 and 28 times increase, respectively. Also, subjects with good levels of ability compared to subjects with excellent levels of ability were 9 times more in exposure of musculoskeletal disorders.
Conclusions: Risk factors such as body mass index, work ability and allowable load lifting limit can affect the prevalence of musculoskeletal disorders. So, selection of subjects with good and excellent work ability levels and compliance with the load limit are the effective solutions in increasing the productivity and reducing musculoskeletal disorders among kitchen workers.
Mehrdad Anbarian, Fatemeh Rajabian, Mohammad Hossein Ghasemi, Rashid Heidari Moghaddam,
Volume 5, Issue 3 (11-2017)
Abstract
Background: The aim of this study was to investigate the effect of the heel wedges on the electromyography activities of the selected left and right lower back muscles during load lifting.
Methods: A total of 17 male subjects voluntarily participated in this quasi-experimental study. The selected subjects lifted a box, weighing 10% of their body weight, above the height of their hip joint, descending as far as the thigh, parallel to the ground, and then ascending to the starting position. The above task was performed nine times in two conditions, including with and without the heel wedges. Using the ME6000 electromyography system, the activity level variables were normalized and the median frequencies of the erector spinae (ES) and the multifidus (MU) muscles were recorded. The subjects also held the box for 30 s in the standing position with stretched hands. The paired t-test was used for the data analysis.
Results: The results showed that during static load lifting using the heel wedge, the median frequency of the right ES muscle changed significantly (P<0.05). Also during dynamic load lifting using the heel wedge, the activities of the left and the right ES muscles as well as the left MU muscle decreased significantly (P<0.05). However, no significant differences between the two conditions were observed for the other variables (P>0.05).
Conclusion: During such occupational tasks, a decrease in the activities of the selected lower back muscles with the heel wedge might result in a delay in the onset of muscle fatigue. The above findings might be used in the design of shoes, suitable for the work environments. However, further investigations are needed in this area in order to provide more accurate results.
Dr Ehsanollah Habibi, Emad Mirsalimi, Faezeh Darabi, Kamran Ebrahimi,
Volume 6, Issue 4 (3-2019)
Abstract
Background and Objectives: This study focused on lifting drill rods. Drilling is a repetitive and heavy mining operation with a high incidence and severity of musculoskeletal injuries. The purpose of this study was to examine how to lift a vertical drill bit (1.61m and 35kg in height) using two types of rod height and four feet positions, and finally compare them with the Lifting Index (LI).
Methods: Seven workers participated in this study. Each person raised a rod and held it vertically. Reflective markers were installed on each person, and from three cameras and an Ergo-meter plate for record forces and Movement of the limbs. In this case, four positions of the foot and pressures on the lower back were Investigated (position0=to the rod, position45=diagonally to the rod, position90=right side of the bar and free posture). In addition, two positions of the height of the rod were Investigated, at the first, the end of rod was on the ground (height of the rod was 83 m), and in the following the end of rod was on the Basket with height 20cm (rod height of 1.03 m).
Results: The Lifting Index (LI) for each person was equal to 1.4 in the NIOSH lifting equation. It was found that the vertical height of the rod had the greatest effect at the load on the lower back. Some workers use techniques that endure less pressure on their waist.
Conclusion: Finally, it was found that the asymmetric loading Condition (90 ° angle) was the worst case compared to the Lifting index and NIOSH standard.
