Repetitive strain injury (RSI)

• What is Repetitive Strain Injury (RSI)?
• Statistics
• Risk Factors
• Progression
• Symptoms
• Clinical Examination
• How is it Diagnosed
• Prognosis
• Treatment
• References

What is Repetitive Strain Injury (RSI)?

Repetitive strain injury refers to damage to any tissue in the body resulting from repetitive demands, rather than a single traumatic event. It occurs over time and it becomes symptomatic when the tissue damage is sufficient to cause pain and dysfunction.

Statistics

The total incidence of repetitive strain injury is not known, however up to 50% of industrial injuries are thought to be attributed to cumulative trauma or overuse injury. These can range from troublesome annoyances, to severe debilitation.

Risk Factors

Occupational environments which involve repetitious activities can often predispose a patient to RSI. High performance athletes and performing artistes are particularly susceptible groups. Race, age and sex are controversial in terms of determining predisposition. RSI can also often be associated with depression.
Injuries associated with repetitive vibration exposure are also particularly susceptible. Also, the greater the force involved, the greater the likelihood of developing an overuse injury.

How is it Diagnosed

Usually no investigations are necessary, however the following modalities may be used in certain cases – Plain x-rays, Bone Scans, MRI and Nerve Conduction Studies.

Prognosis

Overuse injuries occasionally may be resolved permanently with treatment. However most patients often have recurrences of varying severity. In most cases, the patient returns to the activity in question, either due to occupational circumstance or personal preferences. This prompts a recurrence of symptoms. High motivation and commitment to optimizing individual biomechanics, and maintaining an active prevention program (usually including a home exercise program) are common features in patients who remain problem-free, despite returning to the same or similar activities. In cases of defined nerve compression, the surgical release usually is followed by resolution of the symptoms, with low recurrence rates.

Treatment

A rehabilitation program is imperative to the treatment of RSI. This includes the use of physiotherapy (to improve movement, strength and function) and occupational therapy (to implement any lifestyle or work modifications that may be needed). Patient education on safe work practices, appropriate positioning and proper mechanical use is also essential.
Medical therapy may include local joint injections of steroid. Other medical therapies involve the use of NSAIDs, muscle relaxants, narcotic analgesics (for severe pain), tricyclic antidepressants and sedatives. Surgical nerve decompression may be necessary. It is important that psychosocial issues are also addressed.
Patients should be advised to avoid any precipitating activities, however this is very unsuccessful in clinical practice.

References

1. Melhorn JM: Cumulative trauma disorders and repetitive strain injuries. The future. Clin Orthop 1998 Jun; (351): 107-26
2. Sjogaard G, Sogaard K: Muscle injury in repetitive motion disorders. Clin Orthop 1998 Jun; (351): 21-31
3. Ireland DC: Australian repetition strain injury phenomenon. Clin Orthop 1998 Jun; (351): 63-73