What is Occupational Overuse Syndrome (OOS)?
Occupational overuse syndrome (OOS) comprises a range of conditions, such as injury and discomfort or continuous muscle pain, damage to tendons and other soft tissues, with or without any physical signs. Its symptoms develop slowly and is normally caused by work activities involving unsuitable work practices and high-risk jobs having work related injuries, repetitive and forceful actions or awkward postures.
Overuse syndrome is also observed in sports and home activities and should not be confused with other normal home related work discomforts, strain from any physical activity or muscle pains such as arthritis or any other conditions.
OOS is also known as Repetitive Strain Injury (RSI) or Repetitive Stress Disorder (RSD)
Occupational overuse syndrome takes some time to manifest its symptoms after doing any strenuous type of work. There are many theories explaining the causes of OOS. But one theory is as follows, which gives a clear picture about the causes of OOS.
Muscles and tendons are supplied by blood vessels. A tense muscle squeezes on these blood vessels, making them constricted and affects normal circulation. The muscle can store some amount of oxygen to cope with the momentary tension, but when this oxygen is completely utilized, then the muscle must switch to less energy production. This quickly uses the stored energy, making the muscle very tired and causes accumulation of acid waste products; thus damaging the muscle. More build-up of waste products increases the muscle stiffness and greatly disturbs the muscle functions.
Muscles and tendons can resist fatigue and are able to recover if they are made to do a variety of tasks and regular rests in-between.
Factors that can lead to OOS include:
- Awkward postures
- Prolonged muscle tension
- Poor ergonomics
- Repetitive movements
- Forceful holding
- Poor work environment - Poor work techniques, lack of necessary equipment and proper training
- Psychological factors - Unfriendly work environment, deadlines, excessive workload.
The people most affected by OOS are:
- Construction workers
- Meat workers
- Keyboard operators
The signs, symptoms and problems associated with occupational overuse syndrome are:
- Muscle strain
- Numbness and tingling
- Aches and pains
- Muscle weakness
- Disturbed sleep
- Swelling in hands and fingers
- Restricted movement
- Burning sensations in tissues
- Changes in skin color
- Tenosynovitis - It is inflammation and swelling of a tendon due to repetitive movements like typing.
- Carpel Tunnel Syndrome - It occurs when the median nerve gets compressed at the wrist.
- Epicondylitis (Tennis Elbow) - It is a condition in which the outer part of the elbow becomes tendor and sore.
Diagnosing occupational overuse syndrome is a difficult task. It is important that your doctor takes your complete medical history and conduct a physical examination. No laboratory test is useful in diagnosing OOS, but it is usually preferred to rule out other possible causes of pain.
Occupational overuse syndrome can be assessed by many clinical measures such as effort-based tests like pinch and grip strength and diagnostic tests like Phalen's Contortion, Tinel's Percussion for carpal tunnel syndrome, Finkelstein's test for Dequervain's tendinitis and nerve conduction velocity tests that help to detect nerve compression at the wrist.
Other modalities such as X-rays, MRI, bone scanning, and electromyography (EMG) are also employed.
The primary treatment for occupational overuse syndrome is avoidance of the aggravating factors such as work-related stress household activities and other formal work. The common treatments include:
- Application of heat and cold
- Vibration massage
- Anti-inflammatory and analgesic drugs
- Acupuncture & manipulative therapies
- Pain management therapy
- Muscle-strengthening exercises
- Relaxation exercises
Nonsteroidal anti-inflammatory drugs (NSAIDs)are used to reduce musculoskeletal inflammation. Muscle relaxants such as Flexeril and tricyclic antidepressants can benefit in treating repetitive strain injury. Corticosteroid injections, mainly used in combination with local anesthetics, can cure local tendinopathy or tenosynovitis.
It is crucial to change or modify the workplace to remove the factors causing repetitive strain injury.
It is the legal responsibility of every employer to provide a safe and healthy workplace for their employees.
- Provide safe and appropriate equipment at the workplace.
- Provide hand tools that are of comfortable size, shape and weight so that different tasks can be performed without repetitive movements and excessive muscle strain.
- Identification and removal of the precipitating factors in the workplace which can cause Repetitive Strain Injury (RSI).
- Provide training and information to employees about safe working conditions.
- Ensuring that the work equipment are regularly maintained and changed when needed.
- Provide better ergonomics, safe work methods, fewer stress levels, frequent breaks, and adjustable furniture
- Use a chair with a lower back support
- Take regular breaks in between your work
- Set achievable targets
- Make sure that the furniture and equipment are ergonomically designed.
- Workplace Safety - Overuse Injuries - (https://www.betterhealth.vic.gov.au/health/healthyliving/workplace-safety-overuse-injuries)
Latest Publications and Research on Occupational Overuse Syndrome
- Association of Sleep and Hand Function in People With Carpal Tunnel Syndrome. - Published by PubMed