Module 5: Work-Related Musculo-Skeletal Disorders - Risk Factors

WRULDs RISK FACTORS:

WRULDs are caused, aggravated or precipitated by one or more of the following risk factors, singly or in combination:

Task-related factors:

• Highly repetitive upper limb movements.
• Awkward and/or static working postures.
• Movements at the extremes of reach.
• Contact stress (for example, uncomfortable gripping and twisting, sharp edges to hand tools, desk edges, etc.).
• High force requirements.
• Duration of exposure to tasks.

Environmental-related factors:

• Vibration.
• Low temperatures (Cold).
• Lighting.
• Work organisation (for example, rotation, hours, shifts, high task pressure, conveyor belt).

Psychosocial factors:

• Job dissatisfaction: +.
• Monotonous work: ++.
• Perceived intensified work load: ++.
• Lack of job control: ++.
• Lack of job clarity: ++.
• Job stress leading to excessive pressure such as high job demands, time pressures and lack of control.
• Depression / burn out / affirmative action.
• Lack of social support from supervisors or co-workers.
• Ttasks requiring high levels of attention and concentration are related to increased muscle tension, changing thresholds for the perception of pain and fatigue..
• "compensitis".

Individual differences

• All individuals are different and for biological reasons there may be some people who are more or less likely to develop an WRULDS.
• Individual differences may also have implications for employees reporting WRULDS type conditions.
• Genetic predisposition.
• New employees - time to acquire the necessary work skills and/or rate of work.
• Difference in competence and skills.
• Anthropometry - workers of varying body sizes, ie height, reach etc.
• Vulnerable groups, for example, older, younger workers and new or expectant mothers.
• Gender.
• Health status and disability.
• Individual attitudes or characteristics that may affect compliance with safe working practices or reporting of symptoms.
• Smoking: Some association with LBP.

Lower back pain: Occupational risk factors:

• Heavy manual labour.
• Lifting, twisting, awkward motions.
• Sitting.
• Driving, whole body vibration.
• Shorter duration of employment.
• ? Psychosocial: monotonous work, low motivation, lower rating by supervisor.

Lower back pain: Non-occupational risk factors:

• Smoking.
• Taller.
• More births.
• Heavy alcohol.