The significance of back pain among instances of disease in developed industrial societies is currently on the rise. According to data provided by the National Center for Health Statistics in the United States, chronic diseases of the back and of the vertebral column make up the dominant group among disorders affecting employable individuals under 45 in the US population. Countries such as Sweden, which have at their disposal traditionally good occupational accident statistics, show that musculoskeletal injuries occur twice as frequently in the health services as in all other fields (Lagerlöf and Broberg 1989).
In an analysis of accident frequency in a 450-bed hospital in the United States, Kaplan and Deyo (1988) were able to demonstrate an 8 to 9% yearly incidence of injury to lumbar vertebrae in nurses, leading on average to 4.7 days of absence from work. Thus of all employee groups in hospitals, nurses were the one most afflicted by this condition.
As is clear from a survey of studies done in the last 20 years (Hofmann and Stössel 1995), this disorder has become the object of intensive epidemiological research. All the same, such research—particularly when it aims at furnishing internationally comparable results—is subject to a variety of methodological difficulties. Sometimes all employee categories in the hospital are investigated, sometimes simply nurses. Some studies have suggested that it would make sense to differentiate, within the group “nurses”, between registered nurses and nursing aides. Since nurses are predominantly women (about 80% in Germany), and since reported incidence and prevalence rates regarding this disorder do not differ significantly for male nurses, gender-related differentiation would seem to be of less importance to epidemiological analyses.
More important is the question of what investigative tools should be used to research back pain conditions and their gradations. Along with the interpretation of accident, compensation and treatment statistics, one frequently finds, in the international literature, a retrospectively applied standardized questionnaire, to be filled out by the person tested. Other investigative approaches operate with clinical investigative procedures such as orthopaedic function studies or radiological screening procedures. Finally, the more recent investigative approaches also use biomechanical modelling and direct or video-taped observation to study the pathophysiology of work performance, particularly as it involves the lumbo-sacral area (see Hagberg et al. 1993 and 1995).
An epidemiological determination of the extent of the problem based on self-reported incidence and prevalence rates, however, poses difficulties as well. Cultural-anthropological studies and comparisons of health systems have shown that perceptions of pain differ not only between members of different societies but also within societies (Payer 1988). Also, there is the difficulty of objectively grading the intensity of pain, a subjective experience. Finally, the prevailing perception among nurses that “back pain goes with the job” leads to under-reporting.
International comparisons based on analyses of governmental statistics on occupational disorders are unreliable for scientific evaluation of this disorder because of variations in the laws and regulations related to occupational disorders among different countries. Further, within a single country, there is the truism that such data are only as reliable as the reports upon which they are based.
In summary, many studies have determined that 60 to 80% of all nursing staff (averaging 30 to 40 years in age) have had at least one episode of back pain during their working lives. The reported incidence rates usually do not exceed 10%. When classifying back pain, it has been helpful to follow the suggestion of Nachemson and Anderson (1982) to distinguish between back pain and back pain with sciatica. In an as-yet unpublished study a subjective complaint of sciatica was found to be useful in classifying the results of subsequent CAT scans (computer assisted tomography) and magnetic resonance imaging (MRI).
Estimates of the economic costs differ greatly, depending, in part, on the possibilities and conditions of diagnosis, treatment and compensation available at the particular time and/or place. Thus, in the US for 1976, Snook (1988b) estimated that the costs of back pain totalled US$14 billion, while a total cost of US$25 billion was calculated for 1983. The calculations of Holbrook et al. (1984), which estimated 1984 costs to total just under US$16 billion, appear to be most reliable. In the United Kingdom, costs were estimated to have risen by US$2 billion between 1987 and 1989 according to Ernst and Fialka (1994). Estimates of direct and indirect costs for 1990 reported by Cats-Baril and Frymoyer (1991) indicate that the costs of back pain have continued to increase. In 1988 the US Bureau of National Affairs reported that chronic back pain generated costs of US$80,000 per chronic case per year.
In Germany, the two largest workers’ accident insurance funds (Berufsgenossenschaften) developed statistics showing that, in 1987, about 15 million work days were lost because of back pain. This corresponds to roughly one-third of all missed work days annually. These losses appear to be increasing at a current average cost of DM 800 per lost day.
It may therefore be said, independently of national differences and vocational groups, that back disorders and their treatment represent not simply a human and a medical problem, but also an enormous economic burden. Accordingly, it seems advisable to pay special attention to the prevention of these disorders in particularly burdened vocational groups such as nursing.
In principle one should differentiate, in research concerning the causes of work-related disorders of the lower back in nurses, between those attributed to a particular incident or accident and those whose genesis lacks such specificity. Both may give rise to chronic back pain if not properly treated. Reflecting their presumed medical knowledge, nurses are much more prone to use self-medication and self-treatment, without consulting a physician, than other groups in the working population. This is not always a disadvantage, since many physicians either do not know how to treat back problems or give them short shrift, simply prescribing sedatives and advising heat applications to the area. The latter reflects the oft-repeated truism that “backaches come with the job”, or the tendency to regard workers with chronic back complaints as malingerers.
Detailed analyses of work accident occurrences in the area of spinal disorders have only just begun to be made (see Hagberg et al. 1995). This is also true of the analysis of so-called near-accidents, which can provide a particular sort of information concerning the precursor conditions of a given work accident.
The cause of low back disorders has been attributed by the majority of the studies to the physical demands of the work of nursing, i.e., lifting, supporting and moving of patients and handling heavy and/or bulky equipment and materials, often without ergonomic aids or the help of additional personnel. These activities are often conducted in awkward body positions, where footing is uncertain, and when, out of wilfulness or dementia, the nurse’s efforts are resisted by the patient. Trying to keep a patient from falling often results in injury to the nurse or the attendant. Current research, however, is characterized by a strong tendency to speak in terms of multicausality, whereby both the biomechanical basis of demands made upon the body and the anatomical preconditions are discussed.
In addition to faulty biomechanics, injury in such situations can be pre-conditioned by fatigue, muscular weakness (especially of the abdominals, back extensors and quadriceps), diminished flexibility of joints and ligaments and various forms of arthritis. Excessive psychosocial stress can contribute in two ways: (1) prolonged unconscious muscular tension and spasm leading to muscular fatigue and proneness to injury, and (2) irritation and impatience which prompts injudicious attempts to work hurriedly and without waiting for assistance. Enhanced ability to cope with stress and the availability of social support in the workplace are helpful (Theorell 1989; Bongers et al. 1992) when work-related stressors cannot be eliminated or controlled.
Certain risk situations and dispositions may be added to the risk factors deriving from the biomechanics of the forces acting on the spine and from the anatomy of the support and movement apparatus, ones which are attributable to the work environment. Even though current research is not clear on this point, there is still some indication that the increased and recurrent incidence of psychosocial stress factors in nursing work has the capacity to reduce the threshold of sensitivity to physically burdensome activities, thus contributing to an increased level of vulnerability. In any case, whether such stress factors exist appears to be less decisive in this connection than how nursing staff manages them in a demanding situation and whether they can count on social support in the workplace (Theorell 1989; Bongers et al. 1992).
The proper diagnosis of low back pain requires a complete medical and a detailed occupational history including accidents resulting in injury or near-misses and prior episodes of back pain. The physical examination should include evaluation of gait and posture, palpation for areas of tenderness and evaluation of muscle strength, range of motion and joint flexibility. Complaints of weakness in the leg, areas of numbness and pain that radiate below the knee are indications for neurological examination to seek evidence of spinal cord and/or peripheral nerve involvement. Psychosocial problems may be disclosed through judicious probing of emotional status, attitudes and pain tolerance.
Radiological studies and scans are rarely helpful since, in the vast majority of cases, the problem lies in the muscles and ligaments rather than the bony structures. In fact, bony abnormalities are found in many individuals who have never had back pain; ascribing the back pain to such radiological findings as disc space narrowing or spondylosis may lead to needlessly heroic treatment. Myelography should not be undertaken unless spinal surgery is contemplated.
Clinical laboratory tests are useful in assessing general medical status and may be helpful in disclosing systemic diseases such as arthritis.
Various modes of management are indicated depending on the nature of the disorder. Besides ergonomic interventions to enable the return of injured workers to the workplace, surgical, invasive-radiological, pharmacological, physical, physiotherapeutic and also psychotherapeutic management approaches may be necessary—sometimes in combination (Hofmann et al. 1994). Again, however, the vast majority of cases resolve regardless of the therapy offered. Treatment is discussed further in the Case Study: Treatment of Back Pain.
Prevention in the Work Environment
Primary prevention of back pain in the workplace involves the application of ergonomic principles and the use of technical aids, coupled with physical conditioning and training of the workers.
Despite the reservations frequently held by nursing staff regarding the use of technical aids for the lifting, positioning and moving of patients, the importance of ergonomic approaches to prevention is increasing (see Estryn-Béhar, Kaminski and Peigné 1990; Hofmann et al. 1994).
In addition to the major systems (permanently installed ceiling lifters, mobile floor lifters), a series of small and simple systems has been introduced noticeably into nursing practice (turntables, walking girdles, lifting cushions, slide boards, bed ladders, anti-slide mats and so on). When using these aids it is important that their actual use fits in well with the care concept of the particular area of nursing in which they are used. Wherever the use of such lifting aids stands in contradiction to the care concept practised, acceptance of such technical lifting aids by nursing staff tends to be low.
Even where technical aids are employed, training in techniques of lifting, carrying and supporting are essential. Lidström and Zachrisson (1973) describe a Swedish “Back School” in which physiotherapists trained in communication conduct classes explaining the structure of the spine and its muscles, how they work in different positions and movements and what can go wrong with them, and demonstrating appropriate lifting and handling techniques that will prevent injury. Klaber Moffet et al. (1986) describe the success of a similar programme in the UK. Such training in lifting and carrying is particularly important where, for one reason or another, use of technical aids is not possible. Numerous studies have shown that training in such techniques must constantly be reviewed; knowledge gained through instruction is frequently “unlearned” in practice.
Unfortunately, the physical demands presented by patients’ size, weight, illness and positioning are not always amenable to nurses’ control and they are not always able to modify the physical environment and the way their duties are structured. Accordingly, it is important for institutional managers and nursing supervisors to be included in the educational programme so that, when making decisions about work environments, equipment and job assignments, factors making for “back friendly” working conditions can be considered. At the same time, deployment of staff, with particular reference to nurse-patient ratios and the availability of “helping hands”, must be appropriate to the nurses’ well-being as well as consistent with the care concept, as hospitals in the Scandinavian countries seem to have managed to do in exemplary fashion. This is becoming ever more important where fiscal constraints dictate staff reductions and cut-backs in equipment procurement and maintenance.
Recently developed holistic concepts, which see such training not simply as instruction in bedside lifting and carrying techniques but rather as movement programmes for both nurses and patients, could take the lead in future developments in this area. Approaches to “participatory ergonomics” and programmes of health advancement in hospitals (understood as organizational development) must also be more intensively discussed and researched as future strategies (see article “Hospital ergonomics: A review”).
Since psychosocial stress factors also exercise a moderating function in the perception and mastering of the physical demands made by work, prevention programmes should also ensure that colleagues and superiors work to ensure satisfaction with work, avoid making excessive demands on the mental and physical capacities of workers and provide an appropriate level of social support.
Preventive measures should extend beyond professional life to include work in the home (housekeeping and caring for small children who have to be lifted and carried are particular hazards) as well as in sports and other recreational activities. Individuals with persistent or recurrent back pain, however it is acquired, should be no less diligent in following an appropriate preventive regimen.
The key to a rapid recovery is early mobilization and a prompt resumption of activities with the limits of tolerance and comfort. Most patients with acute back injuries recover fully and return to their usual work without incident. Resumption of an unrestricted range of activity should not be undertaken until exercises have fully restored muscle strength and flexibility and banished the fear and temerity that make for recurrent injury. Many individuals exhibit a tendency to recurrences and chronicity; for these, physiotherapy coupled with exercise and control of psychosocial factors will often be helpful. It is important that they return to some form of work as quickly as possible. Temporary elimination of more strenuous tasks and limitation of hours with a graduated return to unrestricted activity will promote a more complete recovery in these cases.
Fitness for work
The professional literature attributes only a very limited prognostic value to screening done before employees start work (US Preventive Services Task Force 1989). Ethical considerations and laws such as the Americans with Disabilities Act mitigate against pre-employment screening. It is generally agreed that pre-employment back x rays have no value, particularly when one considers their cost and the needless exposure to radiation. Newly-hired nurses and other health workers and those returning from an episode of disability due to back pain should be evaluated to detect any predisposition to this problem and provided with access to educational and physical conditioning programmes that will prevent it.
The social and economic impact of back pain, a problem particularly prevalent among nurses, can be minimized by the application of ergonomic principles and technology in the organization of their work and its environment, by physical conditioning that enhances the strength and flexibility of the postural muscles, by education and training in the performance of problematic activities and, when episodes of back pain do occur, by treatment that emphasizes a minimum of medical intervention and a prompt return to activity.