Musculoskeletal Disorders - The importance of a proactive approach

As a physiotherapist working in clinical practice in the NHS, the majority of patients I saw presented with chronic musculoskeletal disorders.  Many had come on insidiously, and the sufferer often could not pinpoint an initial ‘causal' factor.  In terms of the ‘detective' work in making an accurate diagnosis and thus choosing an appropriate course of treatment, this was a disadvantage.  When faced with a known causative incident it is relatively easy to consider the forces that were in play in a particular direction and thereby deduce which muscles, joints, ligaments were most likely to have been compromised.  Without such information, however, the clinician must gather all possible clues about the patient's history and current activities in order to piece together information which may be relevant.  This involves both careful questioning and lateral thinking. 

In fact, most musculoskeletal disorders (MSDs) (with the exception of those caused by an accident, and so involving excessive forces) are cumulative in nature and result from prolonged or repeated low level stress being placed on a tissue.  Each time such stress is applied, ‘microtrauma' - stretching, tearing and ultimately weakening – of the tissue results.  However, as the threshold for generating pain (which serves as a warning of potential tissue damage) is not reached, this goes undetected.  If sufficient time is allowed to elapse before the activity is carried out again, this minor trauma is allowed to heal, and there are no longer term effects.  However if the task – picking up the box, resuming poor posture at the computer, sitting asymmetrically at the reception desk, supporting the phone between shoulder and ear – is repeated without sufficient rest and recovery time, the tissue (already weakened and so vulnerable to additional stress) is damaged further.  Once such damage becomes significant enough, pain is produced.  The sufferer will often incorrectly, but understandably, consider that this is the onset of the condition, when in fact it is merely the onset of symptoms and the condition had been slowly building up for some time. 

The pictures below show examples of tasks involving low – medium level stress which could result in cumulative MSDs:

Figure 1

Monitor placed at angle to body results in rotation of cervical spine, causing sustained muscle contraction on one side and prolonged stretch of tissues on the other.

Figure 2

Leaning forward over a workstation causes prolonged bending of the neck, loss of lumbar lumbar curvature and shoulders to be pulled forward which can contribute to neck, low back and upper limb conditions.

Figure 3

Cradling the phone between shoulder and ear places considerable stress on the musculature of the neck and shoulders.  Prolonged muscle contraction can reduce blood flow and increase likelihood of trauma.

Figure 4

Excessive bending sideways of the wrists during typing away from a neutral, straight line demands considerable muscle action over prolonged periods which can irritate tendons, muscles and connective tissue.

Chronic, cumulative MSDs are easier to prevent than they are to treat.  How, therefore, can we tackle these silent conditions before symptoms arise?  The key here is in prevention through effective risk assessment.  Using the evidence available regarding factors which increase the risk of MSD development, systematic analysis of activities should be carried out and appropriate measures taken to eliminate or reduce this risk.  The most common forms of risk assessment employed in work settings are DSE and manual handling assessments, for which there are a series of standardised assessment tools available.  However, the same principles can be applied to any work activity, task or setting.  It is crucial to be proactive in this approach, taking positive action to identify risks present, not waiting for symptoms to arise to sound those warning bells.  By this time, much of the damage is already done. 

What can be done?

• Adopt a pro-active, system-based approach to the work setting.  Identify all activities in which employees participate and break these down into individual tasks and the actions involved.  Consider factors such as force, repetition, length of time spent in static postures, environmental factors, individual factors, work organisation, psychological factors and rest breaks
• Familiarise yourself with the latest evidence regarding common musculoskeletal disorders and their contributory factors and carry out the initial stage of risk assessment to identify tasks or jobs where risk is high
• Where you deem risk of MSD development to be high, proceed to a more thorough risk assessment, either using an appropriate systematic assessment tool or by seeking professional advice from ergonomics consultants or health and safety consultants
• When MSD symptoms are reported, act swiftly to address all possible contributory factors.  The more quickly action is taken, the more likely the symptoms will subside.  Even if the problem originated outside of work, work activities could be aggravating or exacerbating it, and as such need addressing.

System Concepts have extensive experience in ergonomics, health and safety risk assessments in a wide range of work settings.  We offer practical, realistic advice to workplace issues such as physical layouts, job design and risk assessments alongside a variety of training courses including manual handling and display screen equipment assessment.  For further information contact sue@system-concepts.com

Suggested Reading:

European Agency for Safety and Health at Work Report (1999):
‘Work-related neck and upper limb musculoskeletal disorders' 
available at: http://www.agency.osha.eu.int/publications/reports/201/wruld_en.pdf

National Institute for Occupational Safety and Health Report (1997):
‘Musculoskeletal Disorders and Workplace Factors: A critical review of epidemiological evidence for work-related musculoskeletal disorders of the neck, upper extremity and low back'
available at: http://www.cdc.gov/niosh/pdfs/97-141.pdf