Introduction: National Scope and Severity of MSDs
Dental professionals are exposed to several occupational risk factors that can lead to musculoskeletal disorders (MSDs). Biomechanical and physiological changes due to prolonged static postures, such as sitting, can lead to MSDs resulting in reduced work time or a career ending disability. Although literature of 60 years continues to cite this occupational problem through 2010, the scientific knowledge in biomechanics, kinesiology and occupational health has not been adequately translated into dental or dental hygiene practice. Suggestions to “find a neutral sitting position,” “maintain a neutral posture,” “keep the back straight” or “keeping the head fairly straight,” may be ambiguous and attempts to assume such positions may result in further discomfort or injury.
Musculoskeletal disorders (MSDs) are often chronic, painful and disfiguring. While rarely fatal, MSDs affect the quality of life by preventing individuals from enjoying a healthy and active lifestyle. In addition to personal consequences, these diseases represent an economic loss and social burden for society.
Low back pain (LBP) is currently the most prevalent and costly orthopedic problem in society. In fact, it’s predicted that 80% of adults will experience LBP in their lives1 and 34% who experience LBP will have recurrent episodes.2 While the financial cost of treating low back pain looms in the billions, the cost of declining attendance on productivity in the work-place should not be overlooked either. For example, Americans spend at least $50 billion each year on LBP.
Likewise, LBP is the most common cause of job related disability and the leading contributor to missed work.3,4 Considering these astounding statistics, we must ask if this topic garners interest from any prominent organization positioned to assist with investigating this wide reaching and costly problem. The answer is yes.
The National Institute on Occupational Safety and Health, NIOSH, is part of the Centers for Disease Control and Prevention (CDC) and is the federal research agency established to help assure safe and healthful working conditions. The NIOSH research agenda (NORA) recognizes the extent of MSDs as a societal problem, and identifies the need for research on factors such as posture, movement, and force within the context of temporal factors (duration and frequency).5 Furthermore, prevention of back and other musculoskeletal injuries in the health care sector are recognized as important priority areas, with one of its specific strategic goals targeted at reducing back and shoulder disorders due to patient handling and/or working in awkward postures.6
Capturing data unique to any of the dental professions poses a challenge. First, NORA does not specifically reflect data on the majority of the dental workforce, since national statistics on the self-employed, which includes most dentists, are not gathered by the Bureau of Labor Statistics (BLS) of the U.S. Department of Labor.7However, injuries or illness reported for private and service-providing industries include worker motion or position, injuries involving the shoulder, and injuries from repetitive motion.8 These injuries or illnesses parallel findings from the dental literature. Second, the professional organizations are equally remiss in not collecting data. Both the American Dental Association (ADA) and American Dental Hygiene Association (ADHA) do not collect specific data on MSDs experienced by dentists or dental hygienists. Consequently, there is limited knowledge on the full scope of the problem since current national data are not available on the majority of the dental workforce. What is known has been gathered from multiple small studies conducted among different populations, involving a focus on different body sites and using a variety of survey instruments. Yet, given these limitations, there is consistency in identifying several occupational risk factors that can lead to MSDs in dental professionals. These include the prevalence of MSDs and their distribution among the different body areas, and by the type of practitioner who sustains the injury.9 For example, approximately 60% of both dentists and dental hygienists report lower back pain;10,11 whereas, there is a greater difference reported by these two groups related to hand/wrist pain with a prevalence as great as 69% for dental hygienists and only 54% for dentists.11,12
The statistics clearly support the multifarious costs and prevalence of MSDs in and outside the dental profession. However, the solutions to these problems must be linked to our understanding of anatomy, the movement-related sciences, and risk factors that contribute to MSDs. The next section will provide a review of the risk factors and their associated impact on the musculoskeletal and nervous systems.