The Phenomenon of CTDs and RSIs
Cumulative trauma disorder (CTD) and repetitive strain injuries (RSI) are words used synonymously to describe a phenomenon that is becoming prevalent in the industrial world. CTD and RSI are described as a variety of musculoskeletal disorders relating to tendons, ligaments and joints. They also include nerve-entrapment and vascular syndromes. The injuries usually occur with repetitive motions associated with certain job tasks, awkward positions and other work-related conditions.1
A common CTD is carpal tunnel syndrome (CTS). Atcheson et al report that work-related CTS now account for more than 41% of all repetitive motion disorders in the United States.2 Some common occupations associated with RSI are mail services, health care, construction workers, assembly line workers, fabrication workers, repair services and transportation workers.3 Sometimes one gender is affected more than the other. For example, CTS is more common in the female population.4
There is currently an increase in the trends and prevalence rates of these disorders in relationship to the economics of CTD. For example, in the field of dentistry, dentists in the State of Nebraska were surveyed regarding altered sensations in their hands, arms and forearms. Twenty nine percent of the dentists said they felt pain followed by paresthesia. The prevalence rate of this survey suggests the possibility of an occupational concern.5
The United States Bureau of Labor Statistics and Liberty Mutual Group workers’ compensation claims demonstrate that the trends of CTD in the upper extremities are rising. The data reveals that the injury claim rates are increasing from 1% in 1986 to 4% in 1993. According to Melhorn, CTDs account for 56% of all occupational injuries and occupational injuries currently affect 15%-20% of all Americans.
The US government is predicting that by the year 2000, 50% of the entire American work force will have occupational injuries annually. One study revealed that 80 cents of every Worker’s Compensation dollar is spent in the treatment of common injuries in the workplace.5-8
An answer for the industrial community is difficult to establish. There is limited research to specifically inform employers on how to help reduce CTD and RSI. However, prevention is a key issue in which employers should focus their attention. There are different methods of prevention; one is the study of ergonomics.
Prevention: Key to Ergonomics
Ergonomics in the workplace has been shown to be an effective way for prevention of repetitive motion disorders. There are different definitions of ergonomics, including one by Thibodeau that ergonomics is a scientific, interdisciplinary study of individuals and their physical relationship to the work environment. Ergonomics maximize the production of the workplace while still maintaining the health and well-being of the worker.
Another author writes that ergonomics is the study of the relationship of the body to the machine. It is based on “information from the fields of engineering, biomechanics, physiology, anthropology and psychology. The goal of ergonomic intervention and design is to develop a good “fit” between an individual and a tool, improving comfort, health, efficiency and productivity of work.”9-10
Ergonomic Advantages for Patients
The topic of ergonomics for educational purposes among health care providers is frequently overlooked. However, a great source for information concerning ergonomics can be found among the third largest health care profession in the worldthe chiropractic profession, of course. Doctors of Chiropractic are known throughout the health care community for their knowledge and expertise in the biomechanics of the body’s muscles and joints.8
Consequently, the majority of patients seen in chiropractic clinics have musculoskeletal disorders, many of which may be attributed to poorly designed work-stations or work-habits. In dealing with these types of patients and their complaints, chiropractors utilize ergonomics as a part of their treatment regimens. Patients who return to work with the ability to adapt poorly designed workstations to ergonomically correct designs have better prognoses concerning their health problems.
For example, a patient presents in a chiropractic clinic complaining of dull, nagging neck pain. The patient’s history reveals the person spends several hours of the day in front of a computer screen. The computer monitor sits on the desk approximately eight inches below eye level. This scenario produces poor posture, which promotes an overuse syndrome of the neck and shoulder musculature.
Usually one of the chiropractor’s first questions of the patient is about their work environment. As in this case, the patient may be asked to recreate his or her workstation for demonstration purposes to the doctor. Most often it is discovered that improper workstation design is a major contributing factor to the patient’s primary area of complaint. A simple change in the workstation, such as moving the computer monitor up to eye level, may be one way to dramatically reduce complaints such as headaches and neck pain (Figure One).10
The Benefits to Employees and Employers
As a result of ergonomic adjustments, employees will feel better and visits to health care providers will subsequently decrease over time. In addition, absenteeism of employees is most often reduced and there are fewer complaints among co-workers, which usually results in a better work morale. All of this can be an added economical benefit for the employer. Although this is a simplistic example of what employers can do in their businesses, often these types of alterations in the workstation design are overlooked or ignored.
In addition, there are recommendations the employer can implement that may help minimize work-related medical complaints. There are four ways to do this as explained by Khalil et al.
Model One: Stress Reduction
The first model is stress reduction, which can be accomplished in many different avenues. For example, stress can be lessened by improving poorly designed workstations and resolving conflicts between work colleagues and family. Stress can be a major catalyst for the development of occupational injuries.
Model Two: Proper Design
The second model is to design equipment, workstations, tools and so forth for the worker’s maximum level of comfort, safety and efficiency.
Model Three: Match Capabilities
Model three is to always match job demands to each individual. To enhance comfort and safety, the physical capabilities of the employees need to closely match the work environment. For example, machinery should be designed to be operated while standing stationary. A mismatch can result in injury, health problems, disability and impairment. In consideration of models two and three, the employer should ask these three questions before implementing a program to help combat the national trends of increasing occupational injuries.
- How often will the machinery or equipment be used?
- How long will the tool, chair, etc. be used?
- Who will use the object or equipment?
Model Four: Educate and Train
The fourth model is to educate and train personnel to improve their knowledge of the work environment. Familiarity of the work environment has been shown to decrease occupational injuries, and training increases tolerance levels of stress.11-12
In summary, the trends and prevalence of occupational injuries shows they are on the rise. This can be discomforting for the employer. However, there is help available for employers who are interested in reducing the aforementioned trilogy that is beginning to have dramatic effects on the employees who are involved.
A wealth of knowledge is available to the chiropractic profession concerning proper biomechanics of the body. This can be used as a great resource to employers for the purpose of developing ergonomically correct designed workstations. In addition, an added benefit employers can offer valued employees is to have an active program designed to help reduce work-related health complaints in the workplace, thus promoting a much friendlier working environment.
Wade B. Browne, RN, DC and Joseph E. Goodman, DC are Assistant Professors at Parker College of Chiropractic in Dallas, Texas. Please contact the authors by calling 214-350-1620 or e-mail firstname.lastname@example.org.
Permission was granted by the W.B. Saunders Company to use the diagram in Figure One, “Proper posture and positioning at the VDT.” (Original artwork by Karen Graham, New England Baptist Hospital, Media Production). Gassett RS; Hearne B; Keelan B, Ergonomics and body mechanics in the work place. Occupational disorder management. 1996;27(4):870.
1.Yassi A, Repetitive strain injuries. Lancet 1997;349(9056):943-947.
2.Atcheson SC; Ward JR; Lowe W, Concurrent medical disease in work-related carpal tunnel syndrome. Archives Internal Medicine 1998;158(14):1506-1512.
3.Tanaka S; Wild DK; Seligman PJ; Halperin WE; Behrens VJ; Putz-Anderson V, Prevalence and work-relatedness of self-reported carpal tunnel syndrome among U.S. workers: analysis of the Occupational Health Supplement data of 1988 National Health Interview Survey. American Journal Ind. Med. 1995;27(4):451-470.
4.Dunphy FR; Mannello DM, Chiropractic technique: carpal tunnel syndrome. JACA 1998;35(7):58-61,69.
5.Stockstill JW; Harn SD; Strickland D; Hruska R, Prevalence of upper extremity neuropathy in a clinical dentist population. Journal of the American Dental Association 1993;124(8):67-72.
6.Brogmus GE; Sorock GS; Webster BS, Recent trends in work-related cumulative trauma disorders of the upper extremities in the United States: an evaluation of possible reasons. Journal of Occupational Environmental Medicine 1996;38(4):401-411.
7.Melhorn JM, Cumulative trauma disorders and repetitive strain injuries. The future. Clinical Orthopedics 1998;351:107-126.
8.Chiropractic News Service, Occupational safety programs can reduce workers’ compensation costs through chiropractic. Journal of the Kansas Chiropractic Association. 1998;35(3):23,40,42.
9.Thibodeau PL, Ergonomics in the electronic library. Bulletin Med. Libr. Assoc. 1995;83(3):322-329.
10.Gassett RS; Hearne B; Keelan B, Ergonomics and body mechanics in the work place. Occupational disorder management. 1996;27(4):861-878.
11.Khalil T; Abdel-Moty E; Rosomoff R; Rosomoff H, Ergonomics In Back Pain: A Guide to Prevention and Rehabilitation. Van Nostrand Reinhold, New York 1993
12.Lewis M, Tooling along safely. American Machinist April, 1998.