Text Size:   A+ A- A   •   Text Only
Site Image

Cumulative Motion Injury

ODHHS Information and Technical Assistance Series
Cumulative Motion Injury
(Source: Registry of Interpreter's of the Deaf, Inc.)
Cumulative Motion Injury
Cumulative Motion Injury (CMI), also called Cumulative Trauma Disorder, Repetitive Motion Injury, Repetitive Use Injury, or Repetitive Stress Disorder, can occur in sign language interpreters who perform the same rapid motions multiple times during a work day. Activities that require forceful, speedy, repeated movements, combined with awkward postures and insufficient rest time between movements put interpreters at greatest risk for injuries. The most common injuries are to the wrist (carpal tunnel syndrome), the arm (tendinitis), the shoulder (bursitis) and the back. Cumulative Motion Injury has the potential to prematurely remove people from employment in the sign language interpreting field. Years of education, training and experience may be lost to the practicing interpreter, consumers and employer.
Although Cumulative Motion Injury has traditionally been associated with workers in manufacturing or computer related jobs, doctors are now seeing an increase incidence of such injuries among sign language interpreters. Some causes of Cumulative Motion Injury are:
  • forceful, speedy, repeated movements,
  • awkward hand positions and postures,
  • insufficient rest time between movements,
  • insufficient time for warm up and cool down of muscles,
  • insufficient rest time between periods of intense work,
  • tight muscles in arms and upper body during work time.
Cumulative Motion Injury usually begins as body parts intended to move smoothly together begin to drag against each other. The friction causes tiny tears in muscles and tendons which then become inflamed. As the tears heal, scar tissue forms causing body parts to drag even more against each other. The continuous, repeated friction causes stiffness and pain and inflammation. In the early stages, the pain and stiffness may be reduced when the activity is diminished or go away when the activity is discontinued overnight or for a few days. As the condition grows worse, relief requires longer and longer periods of rest, and the symptoms may recur more quickly on recommencing the activity. In many cases, the symptoms persist and medical attention is required. If the activity is continued without proper treatment and rest, nerve damage results in numbness, loss of strength and flexibility and chronic pain.
Employers concerned about the health and safety of employees can help the interpreter avoid injury. Some preventative measures the employer may take in consultation with the interpreter are:
  • provide 15 minutes of rest or alternative work for each one-and-a-half to two hours of interpreting.
  • utilize more than one interpreter for sessions exceeding one-and-a-half hours. *
  • consider diversification of work duties to include those which do not require use of the same major muscle groups.**
  • provide educational opportunities for the interpreter to learn use of preventative techniques and early recognition of problems.
  • work with the interpreter to analyze the work site to identify and eliminate, when possible, "stressors" such as standing in the same place for a long time, sitting in chairs which are not ergonomically designed, being exposed to extremes in temperature, and assuming awkward positions to interpret.
  • avoid continuous interpreting with heavy work output requiring intense concentration for long periods of time. The amount of time which should be spent in actual interpreting may vary from one job to another.
Since continuous work with little or no breaks can be a strong factor in the onset of CMI***, interpreters should take the initiative in working with employers in identifying and preventing problems by:
  • not working lengthy interpreting situations alone.
  • ensuring sufficient breaks in their work day.
  • not working too many hours in a single day.
Some specific preventative measures interpreters may take are:
  • educate the employer in the use of preventative techniques and early recognition of problems.
  • use a less forceful signing style or fingerspelling with the hand orientation turned slightly in, rather than fully facing the consumer(s).
  • do stretching and range of motion exercises for body and hands.
  • do strengthening exercises for arms and hands.
  • consider alternative preventive and treatment approaches such as therapeutic massage, chiropractic manipulation, paraffin baths, and acupuncture.
There is no one treatment or relief for many of the symptoms of Cumulative Motion Injury(s). Far superior to treatments, prevention of CMI is the best choice for interpreters. A life style for health and fitness combined with prudent work habits can reduce the interpreter's chances of suffering this potentially debilitating condition. Measures employers take to prevent the occurrence of CMI are well worth the costs. Improved performances and bolstered morale can actually reduce employer costs for substitutes, worker's compensation, and health insurance. Working together, employer and interpreter can insure a safe working environment in which the interpreter can work effectively and without risk of Cumulative Motion Injury.
The Association believes that through cooperation with employers, appropriate education, and preventative techniques, the interpreter's years of education, training and experience will not be lost because of Cumulative Motion Injury.
RID has a series of Standard Practice Papers available upon request. Footnotes frequently reference these materials.
* see Team Interpreting
** see Multiple Roles
***RID Views, Vol. 13, Iss. 1, p14