I. What is it?
Repetitive strain injury (RSI) is one of the many names given to describe a group of symptoms that occur gradually over time, in environments where repetitive use of the body occurs without sufficient rest for the tissues. RSI is a self-perpetuating syndrome for which the exact cause is not completely understood. This lack of understanding has led to much variation in the interpretation and treatment of this injury, as well as much frustration and confusion for the injured.

Other names for these syndromes that you may hear a doctor or health practitioner use:

1. Computer Related Injury
2. Myofascial Disorder or Fibromyalgia (if it has persisted for a few years)
3. Occupational Cervicobrachial Disorder
4. Overuse Syndrome
5. Regional Musculoskeletal Disorder
6. Repetitive Motion Disorder or Injury
7. Repetitive Trauma/Cumulative Trauma Disorder or Injury
8. Neurovascular Entrapment Syndrome
9. Work Related Musculoskeletal Disorder (WRMD)
10. Angiofibroblastic Tendinosis

II. Cause: What is believed to happen?
It is believed that injury occurs due to a micro trauma from biomechanical stress to the body’s tissues. Many of us have experienced some of the more “isolated” presentations of RSI at varying levels of severity, like tendon and nerve entrapments (tennis elbow, carpal tunnel syndrome). The initial cause of injury here is that an overuse or trauma to the tissues leads to a cycle of swelling and an increase in pressure which in turn decreases the blood supply to the area and slows tissue healing. In more severe and chronic cases, the cycle becomes unremitting. Pain and swelling seem to now spread in a compartment like fashion from the initial site of injury back and forth to each hemisphere in the body without an apparent cause. The following systems become affected: skeletal, nervous (peripheral and autonomic), muscle/tendon/ligament/bursa, lymphatic, fascial (connective tissue that lines the body and it’s organs), and vascular.

III. Signs and Symptoms
Dysfunction does not usually present itself as a single isolated entity, but as an irritation of multiple structures depending on the severity. Symptoms of RSI are often vaguely described, and difficult to pinpoint. Most complaints are of the following:

1. Pain: achy, burning, sharp, shooting, “itchy” (sign of healing)
2. Decreased range of motion
3. Numbness and tingling (initially may occur at night)
4. Skin discoloration: blanching or bluish finger tips
5. Decreased grip and pinch strength
6. Spasms and tender muscles
7. Cold hands (altered blood flow)
8. Fatigue/feeling of heaviness in the arm
9. Hand tremors/hand cramps (longstanding problems)
10. Pressure sensitivity in the fingertips
11. Clumsiness and incoordination: dropping objects
12. Feeling of swelling with no signs
13. Decreased functional use of the entire arm and neck

IV. Risk Factors
The incidence of computer related RSI disorders has risen drastically since the mid 1980’s, and 62% of all reported work place injuries are for upper extremity RSI. There are many risk factors associated with RSI, however the most damaging ones seem to be those related to tissue injury from sustained postures and high repetition (mouse use>6hours week, typing>4 hours/day) of work with insufficient breaks. The body’s tissues begin to break down when they are subjected to working in poorly designed environments where it has to use awkward postures and excessive grip forces to perform activities on a round the clock basis. Figure 1 describes this unrelenting cycle that takes place in RSI.