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Assessing the Risks

Why does RSI occur?

RSI is not a new phenomenon. It was identified as long ago as 1713 by Ramazzini, an Italian doctor generally regarded as the father of occupational medicine, who recognised that serious disease could be caused by "violent and irregular motions and unnatural postures of the body". Ramazzini described symptoms of RSI in scribes and clerks, noting that the "incessant driving of the pen over paper causes intense fatigue of the hand and the whole arm because of the continuous . strain of the muscles and tendons." In the 19th century the condition was recorded amongst artists, musicians, seamstresses, milkmaids and smiths. And a whole range of popular terms exists to describe musculoskeletal problems associated with particular occupations: telegraphist’s cramp, hop picker’s gout, fisherwoman’s finger, upholsterer’s hand, gamekeeper’s thumb, cotton-twister’s hand, tennis elbow and, more recently, pizza-cutter’s wrist and Nintendonitis.

So RSI has been with us for centuries and many of the risk factors are well established. RSI continues to be the subject of many research studies and recent studies have demonstrated the importance of psychosocial factors in the development of RSI. The main risk factors can be summarised as follows:

• repetitive actions
• forceful movements
• static loading of muscles
• awkward postures
• gripping and twisting
• poor work organisation, including payment systems
• stress
• cold
• vibration

Repetitive work

Jobs requiring highly repetitive motions with short cycles require greater muscular effort and consequently more time for the muscles to recover. Jobs that are paced by machine, for example those on an assembly line, put workers at increased risk of RSI.

Payment by results and similar bonus schemes that put workers under pressure to work even faster will mean that they are working their muscles and tendons even harder and are at even greater risk. They are also under greater mental stress.

Forceful movements

Tasks which place a high load or pressure on the muscles will put greater strain on the muscles and tendons which will become fatigued much more quickly. In addition, poor design of the tool, workplace or task will mean that the worker has to exert excessive force to overcome resistance. If force is applied with the body in a static or awkward posture, the risk will be even greater.

Static or awkward postures

Posture plays a significant role in the development of RSI. Where workers have to adopt a static or awkward posture for long periods, the joints and muscles are put under severe pressure. Awkward postures include those which overload the muscles and tendons in an uneven way and those where a static posture is being held at the extreme of the range of movement for example, with the arms outstretched or above the head, or with wrists bent to the maximum angle, or where the worker has to reach behind their shoulder repeatedly.

Gripping and twisting

Forceful gripping, pinching and clothes-wringing actions can increase the risk of RSI. And constant gripping or pressure on a particular part of the hand, for example a tool pressed against the palm of the hand, can lead to problems in that area.

Poor work organisation

A number of organisational factors are involved in the development of RSI. For example, production lines where workers have a low level of control over the work rate etc., piece rate payment systems or payment by results systems which make earnings dependent on workers achieving excessive work rates, bonus systems which make people overwork themselves, insufficient breaks for rest and recovery, jobs with little variety, and lack of information, instruction and training. Organisational deficiencies which place additional stress on workers such as poor work relationships, lack of consultation, no worker participation in decisions which affect them, job insecurity, and an authoritarian management style can all increase the risk of RSI.

Stress

Although the role of stress is not fully understood, it plays an important part in the development of RSI. It is quite clear that workers under stress are more tense and excessive tension in the muscles is a risk factor for RSI. However, it is important to note that the fact that mental stress may be involved does not mean that RSI is all in the mind as some people try to insist.

Cold

Working in a cold environment or handling cold products such as chilled or frozen foods is an additional risk factor in the development of RSI. Wearing gloves increases the amount of effort needed by the muscles to perform certain tasks such as gripping and can therefore be an added risk factor for RSI.

Vibration

Exposure to vibration is a further risk factor. For example, the use of vibrating tools, particularly where they are used for repetitive and forceful tasks, is known to be associated with carpal tunnel syndrome.

Who is at risk?

Anyone doing a job which exposes them to the risk factors described above is potentially at risk of developing RSI. Women and black workers are at greater risk because they are disproportionately represented in the types of routine, repetitive jobs which are associated with RSI. They have less control over their job and are often concentrated in small, non-unionised workplaces where there is less possibility of achieving change.

Many studies have been carried out to identify occupations at particular risk of RSI. A comprehensive review of such studies is contained in Work related musculoskeletal disorders (WMSDs): A reference book for prevention, by Hagberg, Silverstein et al.

Table 2 gives some examples of the types of job that may lead to RSI, although any badly designed job may cause the problem.

Table 2: jobs with risk of RSI

Assessing whether there is a risk of RSI in the workplace

Employers are required to examine their own organisation and assess whether employees are likely to be at risk of RSI because of the jobs they do and because of any organisational factors. The Health and Safety Executive have produced various checklists that can help them do this. Other checklists are contained in the publications listed at the end of this handbook. The following questions are taken from the HSE leaflet, Upper Limb Disorders: Assessing the Risks.

Are there any factors in the job that make upper limb disorders likely, such as:

Does the job involve:

• strong force at the same time as awkward movements or posture, eg bent wrists, work with arms raised or fully extended?
• forceful use of hand/forearm muscles?
• forcing ill-fitting components into place?
• tools which are not ideal for repetitive or frequent use, particularly if squeezing, twisting or hammering actions are required
• using equipment designed for a larger or stronger person (eg women using tools designed for men)?

Does the job involve:

• machine pacing eg to keep up with a conveyor?
• frequent repetition of the same small number of movements?
• awkward movements such as twisting or rotation of wrist, movement of wrist from side to side, very bent fingers and wrist, or hand or arm movements beyond a comfortable range?
• pressures on employees to work fast, eg from piecework or bonus systems?

Does the job involve:

• cramped body position and/or not enough space to change posture?
• arms stretched or overhead for long periods?
• work at awkwardly high or low height (crouching, stooping or reaching up)?
• poor posture for any other reason?

Does the job involve:

• no changes to work routine or variation of tasks?
• no breaks or infrequent breaks?
• worker not able to have short pauses when desired?

Does the job involve:

• people having to work at full pace immediately they start or resume the job?
• no training in the risk of upper limb disorders and ways employees can reduce risks?

Is the work carried out:

• in dim light, shadow or flickering light?
• in cold or other adverse conditions?
• with tools that vibrate?

Employers should carry out an audit of the jobs and work processes in their organisation using this type of checklist to help them. There are a number of other tools available for employers to audit the jobs in their organisation. One of these is the rapid upper limb assessment (RULA), a simple tool for looking at the physical aspects of the job, developed by McAtamney and Corlett of Nottingham University. It uses a stage by stage approach to assess the posture in different parts of the body and the scores give a risk rating which can be used to determine the preventive action needed. The system has been tested and validated and people can be taught very easily to use it. It is set out in the self-assessment guide, How well is your job designed? published by the Sheffield Occupational Health Project, which explains in simple language how to use the guide to score one’s own job for the strain it puts on one’s body. Tables allow the person to assess how much strain their working postures put on them, and a system of diagrams allows them to identify the position that most closely resembles their own working posture for arms and wrists and for trunk, legs and neck.

The above leaflets do not include detailed questions about the organisational or psychosocial factors of the work that may present a risk of RSI, although other HSE guidance does include these. However, it is important to take all these issues into account as the following case study from the USA shows. There, a major telecommunications company experienced a substantial number of RSI cases amongst telephone operators and, following an investigation during which a number of ergonomic improvements were recommended, it invested in dual-height adjustable workstations, height-adjustable chairs, new computer equipment and improved environmental lighting and noise levels. Two years later, the incidence of RSI remained the same and a further investigation was carried out. This found almost total compliance with ergonomic principles for computer workstations but high levels of employee complaints in respect of psychosocial factors of their jobs. This example shows that efforts to identify and solve RSI problems must address the total work system, which means looking at the psychological fit as well as the physical fit of the job to the worker. The equipment itself may be state of the art but if the work and workplace are not organised properly and if people are working to unreasonable performance targets or piece rate systems then problems will still occur.

The sorts of questions that could be added to the previous list in order to assess the risks from psychosocial hazards include:

Does the job allow:

• no provision for sudden changes in workload?
• no provision for workers to control their own workload?
• no feedback about performance?
• no consultation about changes?
• no participation in decision-making?
• no opportunity for learning?
• no social contact with colleagues?

The results obtained from these checklists will enable the employer to identify the extent of the risk and the action that needs to be taken to minimise the risk of RSI.

Assessing whether there are symptoms of RSI amongst the workforce

As part of the risk assessment process employers should check whether any of their employees are already displaying symptoms of RSI. However, it is important to be aware that:

• many workers may not recognise their own symptoms as RSI
• many workers will be unaware of the serious nature of RSI even if they do suspect the symptoms
• many workers will continue to work regardless of their symptoms
• many workers will be unaware of the importance of reporting their symptoms early
• many workers will be afraid to report their symptoms

Employers should take account of these problems when trying to assess the extent of any existing problem in their organisation.

One way to find out whether employees have RSI symptoms is for employers to look at their accident book and at sickness absence records and to consult their occupational health service if they have one. However, since many employees will not recognise or report symptoms, as already indicated, employers will probably need to carry out a health survey of their employees. This should be done in an open and transparent way and employers will need to explain the purpose of the survey and demonstrate a commitment to resolving any problems whilst guaranteeing employment security to anyone found to have symptoms. If employees suspect that the real motive behind the survey is to weed out people with problems they will not have any confidence in the survey and are unlikely to take part.

The survey itself will have to be appropriate to the purpose and set out in a way that is easy to understand. The language used should be simple, with translations available in any other languages in common use amongst the workforce. The survey form could just be a list of questions or it might incorporate a body map on which workers could indicate sites of pain. The survey form set out in Chapter 6 is an example of a simple form which incorporates questions about symptoms with reference to different parts of the body as well as questions about the job.

The role of trade unions is vital in ensuring that surveys are done properly and are not used to weaken job security and discriminate against workers. The employer should consult the union at every step along the way and obtain agreement for the method to be employed. The union may well prefer to conduct its own survey, especially where there is distrust of management's intentions (see later).