Repetitive strain injury (RSI), also known as Cumulative Trauma Disorder (CTD), occupational overuse syndrome, non-specific arm pain or work related upper limb disorder (WRULD), any joint pain that is believed to be caused by chronic misuse of these body parts, for instance, while using a computer on the job. Conditions such as RSI tend to be associated with both physical and psychosocial stressors.
The following complaints are typical in patients that might receive a diagnosis of RSI:
- Pain in the arm (typically diffuse—i.e. spread over many areas).
- The pain is worse with activity.
- Weakness and lack of endurance.
In contrast to carpal tunnel syndrome, the symptoms tend to be diffuse and non-anatomical, crossing the distribution of nerves, tendons, etc. They tend not to be characteristic of any discrete pathological conditions.
A 2008 study showed that 68% of UK workers suffered from some sort of RSI, with the most common problem areas being the back, shoulders, wrists, and hands.
Physical Examination and Diagnostic Testing
The physical examination discloses only tenderness and diminished performance on effort-based tests such as grip and pinch strength—no other objective abnormalities are present. Diagnostic tests (radiological, electrophysiological, etc.) are normal. In short, RSI is best understood as an apparently healthy arm that hurts. Whether there is currently undetectable damage remains to be established.
The term “repetitive strain injury” is most commonly used to refer to patients in whom there is no discrete, objective, pathophysiology that corresponds with the pain complaints. It may also be used as an umbrella term incorporating other discrete diagnoses that have (intuitively but often without proof) been associated with activity-related arm pain such as Carpal tunnel syndrome, Cubital tunnel syndrome, Thoracic Outlet Syndrome, DeQuervain’s syndrome, Stenosing tenosynovitis/Trigger finger/thumb, Intersection syndrome, Golfer’s elbow (medial epicondylosis), Tennis elbow (lateral epicondylosis), and Focal dystonia.
Finally RSI is also used as an alternative or an umbrella term for other non-specific illnesses or general terms defined in part by unverifiable pathology such as Reflex sympathetic dystrophy syndrome (RSDS), Blackberry thumb, disputed Thoracic Outlet Syndrome, Radial tunnel syndrome, “Gamer’s thumb” (a slight swelling of the thumb caused by excessive use of a gamepad), “Rubik’s wrist” or “cuber’s thumb” (tendinitis, carpal tunnel syndrome, or other ailments associated with repetitive use of a Rubik’s Cube for speedcubing), “Stylus Finger” (Swelling of the hand caused by repetitive use of mobile devices and mobile device testing.), “Raver’s wrist”, caused by repeated rotation of the hands for many hours (for example while holding glow sticks during a rave).
Although Tendinitis and Tenosynovitis are discrete pathophysiological processes, one must be careful because they are also terms that doctors often use to refer to non-specific or medically unexplained pain, which they theorize may be caused by the aforementioned processes.
Modifications of posture and arm use (ergonomics) are often recommended.
Adaptive technology ranging from special keyboards, mouse replacements and pen tablet interfaces to speech recognition software might help improve comfort:
Pause software reminds the user to pause frequently and perform exercises while working behind a computer. One such program is Workrave, an open-source free program that assists in the recovery and prevention of Repetitive Strain Injury. The program frequently alerts user to take micro-pauses, rest breaks and restricts user to a predefined daily limit. A similar program is RSI reminder, by Rob Nebeker; the program is available as a widget (i.e., add-in) for the Google Desktop.
Switching to a much more ergonomic mouse, such as a Roller Mouse, vertical mouse or joystick, or switching from using a mouse to using a stylus pen with graphic tablet may provide relief, but in chronic RSI they may only result in moving the problem to a different area. Using a graphic tablet for general pointing, clicking, and dragging (i.e. not drawing) may take some time to get used to as well. Switching to a track pad, which requires no gripping or tensing of the muscles in the arms may help as well. Inertial mice (which do not require a surface to operate) might offer an alternative where the user’s arm is in less stressful thumbs up position rather than rotated to thumb inward when holding a normal mouse. Also, since they do not need a surface to operate (“air mice” function by small, forceless, wrist rotations), the wrist and arm can be supported by the desktop.
Keyboards and Keyboard-alternatives
Switching to a much more ergonomic keyboard layout such as Dvorak or Colemak may help.
Exotic keyboards by manufacturers such as DataHand, OrbiTouch, Maltron and Kinesis are available.
DataHand Professional II Keyboard, left side
A number of medical treatments, including non-narcotic pain medications, braces, and therapy, exist although some doctors consider these to be palliative. (See Are Some RSI Cases Psychosomatic? below)
Exercise decreases the risk of developing RSI.
Given that main stream health providers are still working on the best approach to RSI, it is not surprising that alternative treatments are popular. Some people with RSI find relief in specific movement therapies such as taijiquan ( t’ai chi ch’üan), yoga, or the Alexander technique.
Doctors often recommend that RSI sufferers engage in specific strengthening exercises, for example to improve posture.
In light of the fact that a lifestyle that involves sitting at a computer for extended periods of time increases the probability that an individual will develop excessive kyphosis, theoretically the same exercises that are prescribed for thoracic outlet syndrome or kyphotic postural correction would benefit an RSI sufferer.
Resume Normal Activities Despite the Pain?
Some researchers believe that, for the most difficult chronic RSI cases, the pain itself becomes less of a problem than the disruption to the patient’s life caused by avoidance of pain-causing activities massive investment of time into increasingly futile attempts at treatment.
They claim greater success from teaching patients psychological strategies for accepting the pain as an ongoing fact of life, enabling them to cautiously resume many day-to-day activities and focus on aspects of life other than RSI.
Others disagree, emphasizing the importance of rest in achieving recovery. For instance, it has been claimed that recovery can take up to 8 months without performing activities that might exacerbate the symptoms, and that the affected joint should never be put under severe or constant stress.