The majority of myo-fascial* injuries are not the result of an accident or sudden mishap. Rather they are injuries that develop gradually over periods of weeks, months or even years as a result of repeated stresses of micro trauma (microscopic injuries/tears) to particular body tissues.
Symptoms such as pain, discomfort, headaches can occur when these actions strain muscles, tendons, nerves and other soft tissues of the body. Damage and pain may occur if strained body parts are not given time to rest and recover. Because of the slow on set and often innocent character of the micro trauma the condition is most often ignored until the symptoms become chronic and permanent injury has occurred.
* (Myofacia-the layers of connective tissue that surround and separates muscle tissue layers. It is also a term that is loosely applied to conditions concerning the muscles, fascia, tendons and ligaments.)
Repetitive Strain Injury or “R.S.I.” is a term given to any number of different conditions which are mainly caused by:
• Frequent and repetitive actions
• repeated forceful movements
• Use of badly designed tools and machinery
• over straining
• Contact with sharp edges or hard objects
• working in cold temperatures
• Use of tools and machinery that vibrate
• poor job training
• Poor work station design
• awkward body positions
• Static or unnatural body positions
• pace of work (too fast/no rest)
Further Contributing Factors:
Fatigue and stress
•after work activities
•Health of the worker
Examples of conditions associated with repetitive strain injuries are:
• Chronic muscle spasm / pain / restriction
• Carpal tunnel syndrome (median nerve compression at wrist)
• Tendonitis (wrist, shoulder, elbow)
• Tenosynovitis including trigger finger (finger)
• Medial epicondylitis (golfer’s elbow)
• Lateral epicondylitis (tennis elbow)
• Thoracic outlet syndrome
(nerve compression syndrome affecting shoulder and arm areas)
• Tension neck syndrome (neck)
What makes ordinary movements such as gripping, twisting, reaching and movement that do not in themselves pose a risk, hazardous? The risk of injury comes when these movements are done in the following manner:
Causes of RSI
Repetition
This is the strongest risk factor. Involves movements repeated over and over such as data entry, which produces physical fatigue with little time for muscles etc. to rest and recover. When the work activity is continued in spite of the developing fatigue injuries occur.
Body positions
1.) Awkward body positions – performing a repetitive task with the joint of the wrist, elbow and or shoulder in the extreme range. These will be horizontal or vertical movements of the wrist to the extreme range and moving the fingers while the wrist is in the extreme position. Unnatural postures and bad seating will speed up the deterioration of discs, resulting in tissue and nerve damage.
2.) Static body positions – performing controlled movements of the upper limbs such as sitting, while stabilizing the shoulder-neck region. The muscles in the shoulder and the neck contract and stay contracted to hold the position stable for as long as the task requires. The neck/shoulder muscles become fatigued, even though there is no movement. The reduced blood supply to the remaining parts of the upper limbs accelerates fatigue in the moving muscles, making them more susceptible to injury.
Force full movement
Exerting force in certain hand positions such as pinch grip on a writing tool put a lot of tension on the tendons in your hands and wrist. More force equals more muscular effort, and consequently a longer time is needed to recover between tasks. Equipment that does not allow the best position of the wrist, elbow and shoulder substantially increases the force required.
Pace of work
This determines the amount of time available for rest and recovery of the body between cycles of a particular task. The faster the pace, the less time is available and the higher the risk of repetitive strain injury.
Stages of Repetative Strain Injuries
Early stages:
Aching and tiredness only during work, settles over night or on days off.
• It’s the kind of pain that is dismissed as part of growing old, or just aches and pains
• There is no reduction in work performance
• takes weeks or months to develop
• This stage is still reversible
Intermediate stages:
Aching and tiredness starts early and persists longer
• don’t settle well at night / disturbed sleep many times
• There is a marked reduction in production at work or at home
Late stages:
The symptoms persist and pain is experienced all the time
• Usually preventing sleep or frequently disturbing sleep
• finds light duties unbearable
• This may be permanent