1. WHAT IS ERGONOMICS?
Ergonomics is the study of people in their workplace and is the process in which workplaces, products and systems are designed or rearranged so that they fit the people who use them. It aims to improve workspaces and environments to reduce the risk of injury.
Physical Ergonomics places a greater emphasis on the human anatomy, physiology, and biomechanical factors influencing movement patterns and posture. This area of ergonomics is therefore of significant interest to physiotherapists and one in which we regularly address due to having a rich, in-depth understanding and knowledge of these factors.
Ergonomics is a science-based discipline. It brings together knowledge from anatomy and physiology, psychology, engineering and statistics and ensures that the designs complement the strengths and abilities of people who use it
Ergonomics Process Include:
- Assess Risks
- Plan Improvements
- Measure Progress
- Scale Solutions
⇣
⇣
⇣
HOW ERGONOMICS WORK
Data and information are collected from various disciplines and is used to design an equipment, modify or rearrange them in a way that it benefits people using them and helps to reduce the risk injuries that can happen. These are the key areas;
- Anthropometry: body sizes, shapes; populations and variations
- Biomechanics: muscles, levers, forces, strength
- Environmental physics: noise, light, heat, cold, radiation, vibration body systems: hearing, vision, sensations
- Applied psychology: skill, learning, errors, differences
- Social psychology: groups, communication, learning, behaviors.
- Mechanical and industrial engineering
- Industrial design
- Information design
- Kinesiology
- Physiology
BENEFITS OF ERGONOMICS
In workplace, when body is stressed by an awkward posture, extreme temperature, or repeated movement, the musculoskeletal system can be affected. Hence ergonomics play major role in reducing these work related injuries or illness like computer vision syndrome, neck and back pain, and carpal tunnel syndrome etc.
To create safe, comfortable and productive workspaces by bringing human abilities and limitations into the design of a workspace, which includes the individual’s body size, strength, skill, speed, sensory abilities and attitudes.
To make employees more comfortable and increase productivity.
Other Benefits of Ergonomics
- Reduced risk of work related injuries and illness
- Higher productivity
- Improved health
- Improved mental insight
- Better product quality
- Decreased pain
- Happy employee
- Improved employee engagement
- Better safety culture
2. BACK PAIN & SITTING ERGONOMICS
Ergonomics is important because it improves workplace performance. Ergonomics are an important consideration both when working from home and in the workplace.There is a link between work-related ergonomics and back pain. Explanations suggested for the high incidence rate are awkward or tiring body positions, keyboard work (desk sitting), repetitive actions, and poor manual handling
The lumbar spine is where most back pain occurs, in and around the five vertebrae (numbered L1-L5) ]. In between each vertebra, there is an intervertebral disc. This is known as the intervertebral disc joint. There are also two (left and right) facet joints between each vertebra. L5 is also attached to the sacrum. The sacrum then attaches to the pelvis, creating the sacroiliac joint.
Structural Function
The main function of the lumbar spine is to bear the weight of the body. It absorbs the stress of lifting and carrying objects as well as general movement. Below are the structural function of the spine:
The spine holds an increasing amount of weight as you move down into the lumbar region. For this reason, the lumbar vertebra has the larger bodies in the spine.
Due to the relative size of the spinous process and body, the lumbar spine has the largest degree of extension. The lumbar spine allows flexion, extension, and lateral flexion but not rotation and this is due to the orientation of the facet joints.
The mammillary process provides an attachment point for many lower back muscles.
The Intervertebral Disc
Between each vertebra, there is an intervertebral disc. The intervertebral disc is made out of the nucleus pulposus, annulus fibrosis, and the cartilage endplates.
Effect Of Sitting On Anatomy
There are many studies that look into how sitting affects our spine, some of these even look into how we change physiologically.
One study found that when flexing the spine, to flatten the lumbar spine, improves the transport of metabolites in the intervertebral discs, reduces the stresses on the facet joints and gives the spine a high compressive strength. This suggests very positive effects of flexing the spine. However, this study did also report negative effects including increasing stress on the annulus fibrosis and increasing the hydrostatic pressure in the nucleus pulposus. It is also important to consider that this paper is from 1985 and does not discuss who participated in the studies and therefore this may not be generalizable to the population as a whole. Further studies have found that sitting in a flexed position also reduces the activity of abdominal muscles which play a key role in stabilizing the back.
Finally, a recent study found that when a person sat for prolonged periods of time (for 4 hours), there was a significant reduction in the height of L4-5 intervertebral disc. However, the sample size had a female predominance and studies have found that males and females do respond to static lumbar flexion differently and therefore this may not be generalizable to the population as a whole.
Sitting and low back pain
Low back pain can be defined as pain originating in the low back region that may or may not radiate down into the legs.This pain can further be categorized by sensation such as dull or sharp pain as well as duration:
- Acute (<6 weeks)
- Sub-acute (6-12 weeks)
- Chronic (>12 weeks)
Occupational low back pain is one of the most prevalent types of back pain. Multiple factors can be responsible (e.g. heavy lifting and poor manual handling) putting multiple professions at risk.
The main causes for this sitting induced back pain have been identified as:
- Sustained sitting
- Increased activation of the spinal muscles due to specific sitting postures
- Lack of variation of movement
As a result of the high prevalence of this occupational back pain extensive government guidance exists for both employers and employees to follow:
3. ERGONOMIC EDUCATION
What Is A Good Sitting Posture?
Workstation design is important to ensure the individual’s body is supported and well-aligned.
- Feet must be supported.
- Knees bent at 90 degrees and thighs parallel to the floor.
- Lumbar support must be provided to maintain the natural curvature of the spine.
- Elbows should be supported on the armrests or desk.
- The monitor has to be at about arm-length distance and at eye-level or slightly lower.
- The individual shouldn’t have to rotate the body to reach the computer or desk.
- Sufficient leg space is also important.
Protecting our lower back when sitting is multifactorial. The factors like the environment, time and posture influence lower back pain. Adapting our environment is important for low back pain. This includes making sure our eyes are inline with monitors, devices such as keyboards are close and chair is in a good height.
The length of time we sit may also have an impact on lower back pain. Recent evidence has proven that sitting time is positively associated with LBP intensity. It is recommended moving every 20 minutes in order to reduce the likelihood of lower back pain caused by sitting.Sitting for more than half a workday and sitting in an “awkward posture” significantly increases the likelihood of low back pain. posture does impact back pain, but usually when maintained for a long period.
Movement For Prevention And Rehabilitation Of Sitting Related Low Back Pain (Frequent breaks)
The key issue with office or desk work is the fact that most individuals go hours without moving their body. This restricts blood flow, fatigues postural muscles and increase tightness. use of microbreaks and taking short active breaks every 20 minutes is optimal.These microbreaks improve comfort, relieves pain and enhances productivity.
Various interventions are used across the spectrum of occupational settings in an attempt to both minimize the risk of low back pain arising but also reduce the impact of sitting on those with already existent low back pain. interventions as sit-stand workstations, help in reducing both the intensity and presence of low back pain for sitting based individuals at work. Another movement based intervention involves the use of “dynamic sitting” which involves the use of both active and passive implements to encourage regular movement of the trunk and lower extremities in a seated position.
Use Of Equipment For Prevention And Management
With back pain being such a common issue, the market has been flooded with equipment to try and alleviate back pain or relieve the symptoms. The equipment ranges from exercise balls and back braces to standing desks. Research has been carried out on all the equipment to varying degrees.
a) Back Support Seat Attachment
A variety of seat attachments exist, for chairs in the office, at home and in the car, which help to reduce lower back pain.
b) Back Braces
when combined with physical therapy and pain medication, there is increased mobility and pain scores with a back brace compared to without.
c) Standing Desks
Standing desks for workplaces have grown in popularity in recent times, orbiting the idea that standing and moving are beneficial to reducing back pain. They allow you to work in a standing posture when necessary, and being able to adjust back to normal desk height to allow for flexibility. Standing desks reduce both the severity and risk of lower back pain.
4. Back Pain Advice For Employers
Low back pain is common and can be extremely painful. It can be difficult to cope with the severe pain but fortunately it is rarely due to serious disease. There are things that employers can do to manage back pain and other musculoskeletal disorders (MSDs) in the workplace. People can be helped to remain in work or helped to make an earlier return to work.
You must:
- Avoid work activities that can cause back pain, where reasonably practicable
- Where the activity can’t be avoided, assess it to see what you can do to reduce the risk of back pain
- Apply the control measures you have identified and monitor and review them to make sure they are working
- Consult your workers and, if they have health and safety concerns, do something about them
Legal Duties
Employers have a legal obligation to protect the health and safety of their employees and other people who might be affected by what they do. Some health and safety regulations are particularly relevant to dealing with back pain in the workplace.
The Management of Health and Safety at Work Regulations requires that all employers assess the risks to the health and safety of their employees while they are at work.
The Manual Handling Operations Regulations require an employer to carry out a risk assessment on the manual handling tasks that pose a risk of injury.
Health and Safety (Display Screen Equipment) Regulations as amended (DSE Regulations) – some users of visual display units may get aches and pains, including back pain. The regulations set out what employers need to do if their employees are habitual users of DSE. Specific advice on DSE and the DSE regulations.
The Control of Vibration at Work Regulations – regular long-term exposure to whole body vibration (WBV) is associated with back pain. The regulations require an employer to take actions to protect persons against risk to their health and safety arising from exposure to vibration at work.
Back Pain in the Workplace
Causes of Pain
Back pain can be caused by different work factors. The exact cause is often unclear, but back pain is more common in occupational roles that involve:
- Repetitive tasks – such as manual packing of goods
force – heavy manual labour, handling tasks, pushing and pulling loads that require excessive force - Posture – poor/ awkward postures such as stooping, bending over or crouching
- Duration – maintaining the same position for long periods of time e.g. working with computers or driving long distances. Also working when physically overtired
- Vibration – operating vibration tools
- Cold temperature – working in low temperature environments e.g. outdoor working in winter
Some work tasks can cause back pain or make existing pain worse:
- Lifting heavy or bulky loads
- Carrying loads awkwardly, possibly one-handed
- Pushing, pulling or dragging heavy loads
- Manual handling in awkward places, such as during delivery work
- Repetitive tasks, such as packing products
- Bending, crouching or stooping
- Stretching, twisting and reaching
- Being in one position for a long time
- Working beyond your capability or when physically overtired
- Working with display screen equipment (with poor posture)
- Driving long distances or over rough ground, especially if the seat is not, or cannot be, properly adjusted or operating heavy equipment (for example excavators)
Manage the risk of back pain
You can reduce the risk of back pain in your workplace:
- Identify what activities can cause back pain and decide whether they can be avoided or changed
- Ask your workers for input – they have first-hand knowledge of the work and can suggest changes
- Think about how you can make jobs physically easier, for example, by moving loads on wheels
- Make sure controls, for example lifting aids, are available, used and maintained
- Look for signs of back pain among your workers, such as a reluctance to do a particular task, which may suggest your controls are not working
- Encourage them to report problems early to you or their worker representative so they get the right help
People with back pain usually recover completely if the problem is recognised early and treated appropriately.
Consult Your Employees
You have a legal duty to consult with all your employees or their elected representatives. Talking to your staff is good because they know what they find difficult and often have good ideas about how to improve things.
Involving employees and safety representatives in discussions about how to improve health and safety will also make it easier to agree changes and employees will be more likely to follow procedures that they have helped to design. Some people are more susceptible to back pain than others, so it is important to consult employees in the risk assessment process.
Predisposing Factors
Many factors increase the risk of developing back pain.
Some of these factors are important risk factors for the development of persistent back pain.
- Previous back injury – the single best predictor of back pain is a previous injury. Relapses are common after a significant episode of back pain
- Smoking – studies have shown that smokers are at greater risk of developing back pain than non-smokers. It is thought to be due to reduced oxygen supply to the spinal discs and decreased blood oxygen from the effects of nicotine on constriction of the arteries
- Level of activity (physical fitness) – the strength and endurance of the back and abdominal muscles have been shown to be related to the development of back pain. Studies have shown that physical fitness and conditioning may prevent back injuries
- Obesity – studies have shown an increase in back pain in obese individuals
- Sports and hobbies- such as skiing, gymnastics and contact sports such as football and rugby increase the risk of developing back pain as a result of injury
- Psychological and social factors- it is increasingly recognised that a wide variety of psychological and social factors can increase the risk of back pain. Research has shown anxiety, depression, job dissatisfaction, mental stress at work can place people at increased risk for developing chronic back pain
Risk Assessment
Risk assessment is a five stage process and involves:
- Looking for the risks (hazards)
- Deciding who might be harmed
- Evaluating the risks and deciding whether the existing precautions are adequate or whether more should be done
- Recording your findings and telling your employees about them
- Reviewing your assessment and revising it if necessary, for example if the work changes significantly; if there is an accident; or when someone returns to work after sickness or injury, or suffers a change in their health, that could affect or be affected by their work
We provide General advice on how to carry out a risk assessment.
Risk Assessment Aids, Tools and Checklists
A number of risk assessment aids, tools or checklists have been developed that will help you assess the risks from some of the manual handling activities that your workers may carry out.
A body mapping tool can be used to collect some basic statistical information from your employees on pain experienced during working. It draws on direct experience of employees themselves and it helps develop an understanding of the shared risk-factors in the work they do.
If your employees are carrying out manual labour then you will need to consider a risk assessment tool that assesses the risks of manual handling. We have the Manual Handling Assessment Chart (MAC), which can be used to help identify high-risk tasks. The MAC does not comprise a full risk assessment, as some aspects, such as pushing and pulling, are not covered.
If your employees work with computers then you will need to perform a display screen equipment (DSE) risk assessment.
If your employees’ work duties involve repetitive or forceful actions, twisting, pushing, pulling, lifting, reaching movements or poor posture, they may be at risk of upper limb disorders (ULDs) and back pain and therefore you will need to carry out a ULD risk assessment.
We provide the guidance booklet Upper limb disorders in the workplace can be used as an aid to risk assessment. They are intended to help employers identify the potential risks and possible ways to reduce them
Manual Handling Risk Assessments and Specific Tools
Things to remember about manual handling risk assessments:
- Risk assessments are not an end in themselves they are a structured approach to analysing risk and should point the way to practical solutions
- A risk assessment should cover all standard operations, including cleaning and maintenance activities. It should reflect how the work is actually done
- The main areas to focus on are the task – load, working environment and individual capability
Once the risk assessment is completed you should now review ways in which to eliminate or reduce the risk of employees developing back injury in your workplace.
This will often involve redesigning the task (to reduce the amount of manual handling or exposure to the risks) and may involve the introduction of mechanical lifting aids that can support the weight of the load and therefore potentially reduce the risk of back injury.
There are a number of different companies that produce manual handling lifting aids to reduce the manual handling risks to the employee and therefore reduce the risk of developing back pain.
Making the best use of lifting and handling aids’ provides information of some of the different aids available. This list is not exhaustive and there are a number of different aids available for a variety of different work processes.
The guidance on the Manual Handling Regulations contains a risk assessment filter to help you screen out low risk manual handling activities.
The filter allows you to identify those manual handling tasks that may be categorised as hazardous and pose a risk of injury. As a result a more detailed risk assessment is required.
Application of the filter guidelines will provide a reasonable level of protection to around 95% of working men and women. However, the guidelines should not be regarded as safe weight limits for lifting.
There is no threshold below which manual handling operations may be regarded as ‘safe’. Even operations lying within the boundary mapped out by the guidelines should be avoided or made less demanding wherever it is reasonably practicable to do so.
Other Risk Factors
Research has shown that there are other risk factors that can affect an employee’s physical health.
Within the work setting, examples of these other risk factors are:
- High workloads
- Tight deadlines
- Lack of control of the work and working methods
- Working relationships with supervisors and colleagues
These risk factors can lead not only to stress but also to back pain. For example, stress related changes in the body, such as increased muscle tension, could make employees more susceptible to back pain, or changes in behaviour such as not taking breaks to try to cope with deadlines.
These other risk factors are also known as psychosocial risk factors. Psychosocial risk factors are about the interaction between a person and their social or work environment and the influences on their behaviour.
You may also like to look at our topic area on tackling work related stress and the management standards. The management standards give advice on issues like work load and patterns.
Preventing Back Pain
Active work is good for your employees.
Active work has a positive impact on individuals’ physical and mental wellbeing.
The idea that manual handling or repetitive movements is ‘bad for employees’ is a myth but it is true active work approached wrongly can sometimes contribute to health conditions like back pain and other musculoskeletal disorders (MSDS) such as muscular aches and strains.
What Can I Do To Help Protect Employees?
As an employer you have legal obligations to provide safe and healthy workplaces for employees.
The physical demands of some tasks like manual handling, lifting, bending and driving heavy vehicles can trigger an episode or make an existing back pain worse.
Take steps to reduce the risk of back pain in the workplace.
You should:
- Provide information, training and supervision on safe ways to work
- Carry out risk assessments conducted by trained assessors to minimise risks
- Provide safe equipment to assist your employees in their duties
- Consult regularly with the employees on their health and well being to help you identify concerns and developing trends
- Take actions to address any outcomes from these discussions
- Respond promptly when an individual employee reports back pain
- Talk to employees and get them to suggest ideas and discuss possible solutions for high risk tasks/activities
- Make changes to work environment and work style as far as is practical i.e. vary tasks to give employees a range of postures
- Consider ways in which you can make jobs physically easier and safer to perform, e.g. by moving loads on wheels, providing better handles on loads, adjusting heights of worktops etc.
- Consider Job Enlargement/ Job Rotation- to reduce physical and mental fatigue
- Encourage employees to warm up to prepare their bodies for heavy or repetitive work (e.g. general stretch of all major muscle groups or gentle jog on the spot)
- Encourage employees to adopt correct postures for the tasks they do at work and home
- Ensure employees take allocated breaks and leave work on time
- Make employees aware of the predisposing factors for back pain e.g. poor physical fitness, psychosocial issues and smoking
consider basic ‘health promotion in the work place’ tips. – This might include advice or information about walk or cycle to work schemes and providing information sessions for employees on important health issues
Early Access to Advice and Helping Employees Return to Work
The occupational health professional will be able to highlight any work factors that are causing difficulty and should liaise with supervisors or managers if necessary in order to help the person stay at work or return to work. Some cases will require monitoring by occupational health professionals with a review of progress at regular intervals. Some individuals such as those with a serious condition or serious back injury may be under the care of their GP or hospital specialist.
While they are absent from work long term, occupational health professionals will be in a position to liaise with the GP or specialist to gain further information on the diagnosis and the plans for medical management including time frames. This will enable you to plan your work and arrange for cover as needed.
Early access to advice
This service could be used for employees with back symptoms who are still at work or any who are on sick leave.
Occupational health professionals with experience of back problems and workplace situations (occupational physiotherapists, occupational therapists or other appropriate health professionals) are able to give appropriate advice via face- to-face appointments or telephone contact. The system should include assessment of clinical priority. Severe conditions linked to back pain are rare. An individual with serious symptoms would be directed to seek medical attention as appropriate as they may need urgent treatment from the .Other individuals can be reassured and given appropriate advice with a follow up contact arranged if necessary.
Extra Help In Returning To Work
If someone is off work or unable to work normally due to back pain or injury and they have continued to have problems for 4-6 weeks, you can invest in a particular type of scheme to help restore function to the employee. This is called a functional restoration programme. There is strong evidence from good quality research for the effectiveness of this process. Gradual strengthening takes place under the supervision of occupational physiotherapists or occupational therapists. These professionals are able to assist employees to overcome any barriers such as fear of further injury and get them to carry out work-oriented tasks with the aim of going back to the original job. You should be aware that an exercise programme is not the same as a functional restoration programme and will not give the same benefits to the employee.