In contrast to the extensive studies of low back pain in the work place, there is a surprising lack of information regarding occupational neck pain. Like back pain, the prevalence of neck pain in the general population in industrialized societies is quite high. While not as common as low back pain, it is estimated that the one year prevalence of neck pain is approximately 20%. Studies in Scandinavia have reported a one year prevalence rate of 16% in men and 18-20% in women (Anderson, 1971). If neck pain is defined as an episode lasting two weeks, the prevalence in men and women was 8.2% among persons 25-74 years of age. The highest prevalence (10.1%) was among persons 45-64 years of age (Praemer et al., 1992).
In another study, a questionnaire inquiring about neck pain was sent to 10,000 Norwegian adults. A total of 34.4% of the respondents had experienced neck pain within the last year, with 13.8% reporting neck pain that continued for more than six months (Bovim et al., 1994). In general, it appears that cervical problems occur one-fourth to one-half as often as low back pain (Anderson, 1971).
With consideration to the work place, neck injuries represent less than 2% of all work place injuries. The majority of these are diagnosed as sprains and strains, and many occur as the result of work-related automobile accidents. In fact, it is estimated that 85% of all neck injuries seen clinically are the result of automobile accidents (Borenstein et al., 1996). In a retrospective study of 1,661 patients seen in a pain clinic over a 10-year period, 55 patients presented with a primary complaint of intractable neck pain. In 89%, there was either an industrial or motor vehicle accident as the precipitating event (Abbott et al., 1990).
The National Council on Compensation Insurance shows an incidence rate for neck injuries of 1.1%. A review of the type of occupational accidents resulting in neck injuries showed that 53% were the result of automobile accidents. Falls accounted for an additional 10% of neck injuries; 13% were the result of being struck by some type of object; 12% resulted from awkward working postures; and 10% were the result of material handling (National Safety Council, 1978).
In addition to neck pain occurring as a direct result of on-the-job automobile accidents, certain occupations appear to have a predisposition for neck problems. As an example, studies of machine operators, carpenters, and office workers have shown a lifetime prevalence of neck and shoulder symptoms of 81%, 73%, and 57% respectively (Tola et al., 1988). A high prevalence of neck problems has also been demonstrated in sewing machinists (98%), teleprinter operators (69%), microscopists (66%), and seamstresses (60%) (Grieco, 1986). Workers involved in manual tasks have more problems than office workers. Also, the type of manual task seems to affect the risk of symptoms. Laubli (1984) demonstrated that, for individuals using keyboards at work, the number of keystrokes per day was an important factor in the development of neck pain and/or arm pain (Laubli, 1984).
According to Pheasant, the most common cause of work-related neck problems is the static loading which results from faulty working postures. In occupational groups with a high prevalence of neck pain, there are a number of common denominators. Workers are required to fix their eyes on a single point while performing some task with the hands. This effectively fixes the posture of the head, neck, shoulders and arms. In addition, a great deal of concentration is required, providing little opportunity for moving around. Neck and shoulder problems also occur in people who work for long periods with their arms in a raised position (Pheasant, 1991). In a study of Swedish electricians, work performed with the neck in extension and with the hands above shoulder height caused increased neck pain (Sandmark and Nisell, 1994). Grandjean states that in typists reporting neck and shoulder symptoms, the majority blame the condition on a desk top that is too high (Grandjean, 1987).
One significant difference between low back pain and pain in the neck is the age of those affected. Low back pain is the leading cause of work absenteeism in individuals between the ages of 19 and 45. As we age, however, there is a decrease in both the incidence and impact of low back pain. After the age of 45, other conditions such as heart disease and rheumatism produce more disability than low back pain (Kelsey et al., 1979). Unlike low back pain, that tends to decrease in severity with advancing age, neck pain appears to become more prevalent. In a study of 1,137 working men (25 to 54 years of age), neck pain occurred in 27% of those younger than 30 and in 50% in those older than 45 years of age. Arm pain occurred in only 8% of those under 30, but in 38% of those over 45 (Hult, 1954).
One of the problems with occupational neck pain is a lack of uniformity of the terms used to describe neck injuries. The term "occupational cervicobrachial disorder" is used to describe various conditions resulting in symptoms of pain in the neck, paracervical musculature, and shoulders (Leffert, 1992). Because of such diagnostic uncertainty, it is largely impossible to develop any meaningful comparisons between groups of workers described in the literature.
The evidence supporting manipulative treatment for low back conditions is mounting. It is currently acceptable to the scientific community to make the claim that spinal manipulative therapy (SMT) has a valid role in the treatment of certain types of back pain. The evidence for the use of SMT in the treatment of neck and shoulder problems is not as convincing. It is apparent that industry must take a closer look at the problem of neck pain. It is also clear that the chiropractic profession must continue to investigate the role of manipulation in the management of cervical conditions.
References
- Abbott P, Rounsefell B, Fraser R, Goss A. Intractable neck pain, Clin J Pain, 6(1):26-31, 1990.
- Anderson JAD. Rheumatism in industry: A review, Br J Ind Med, 28:103, 1971.
- Andersson GBJ, McNeill TW. Lumbar Spine Syndromes, Evaluation and Treatment, Springer-Verlag, New York, 1989.
- Borenstein DG, Wiesel SW, Boden SD. Neck Pain: Medical Diagnosis and Comprehensive Management, W.B. Saunders Company, Philadelphia, 1996.
- Bovim G, Schrader H, Sand T. Neck pain in the general population. Spine 19:1207, 1994.
- Grandjean E. Ergonomics in Computerized Offices, Taylor and Francis, New York, 1987.
- Hult L. Cervical, dorsal, and lumbar spinal syndromes. Acta Orthop Scand Suppl. 17:1, 1954.
- Kelsey J, White A, Pastides J, Bisbee G. The impact of musculoskeletal disorders on the population of the United States, J Bone Jt Surgery Am, 61:959-964, 1979.
- Kirkaldy-Willis WH. Managing Low Back Pain, 2nd ed., pg. 4, Churchill-Livingstone, New York, 1988.
- Laubli T, Grandjean E. The magic of control groups in VDT field studies. IN E. Grandjean, ed., Ergonomics and Health in Modern Offices. Taylor & Francis, London, 1984.
- Leffert RD. Disorders of the Neck and Shoulders in Workers, In: Occupational Disorders of the Upper Extremity, ed. Millender LH, Louis DS, Simmons BP, Churchill-Livingstone, New York, 1992.
- National Safety Council: Accident Facts, Chicago, National Safety Council, 1978, 26.
- Pheasant S. Ergonomics, Work and Health, Aspen, Gaithersburg, 1991.
- Praemer A, Furner S, Rice DP. Musculoskeletal Conditions in the United States, Illinois: American Academy of Orthopedic Surgeons, 1992, 23-33.
- Sandmark H, Nisell R. Measurement of pain among electricians with neck dysfunction. Scand J Rehabil Med. 26(4):203-9, 1994 Dec.
- Tola S, Riihimaki H, Videman T, et al. Neck and shoulder symptoms among men in machine operating, dynamic physical work and sedentary work. Scand J Work Environ Health, 14:299, 1988.
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I may also be contacted at Los Angeles College of Chiropractic, 16200 East Amber Valley Drive, Whittier, CA 90609 If you have questions, you may reach me at 909-598-6344 or at
Paul Hooper, DC
Diamond Bar, California
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