Note: This report is a translation of the original Paris Task Force report, written in French and entitled “Place de l’activité dans la prise en charge thérapeutique des rachialgies.” This translation is completely faithful to the original text and has been endorsed by the entire Task Force. The translation was entrusted to Steven Sacks, Les Services Organon (Montreal, Canada).
SUMMARY AND RECOMMENDATIONS
Rest and Activities of Daily Living
For years, rest has been an essential therapeutic recommendation in cases of low back pain with or without sciatica. This spectacular analgesic effect has led to the development of a sort of medical dogma concerning the prescription of rest in cases of low back pain, and even to its imposition on patients who think it unnecessary. It is only recently that the evolution of low back pain has been objectively studied in clinical trials, most of which have concluded that prolonged rest serves no purpose and delays return to work and activity.
The Task Force recommends (Table 1), on the strength of its literature review that in acute cases in diagnostic Categories 1, 2, and 3, bed rest should neither be enforced nor prescribed, but may be authorized if the pain indicates it. If authorized, it should be of as short a duration as possible and should be intermittent rather than continuous. After 3 days of bed rest, patients must be strongly encouraged to progressively resume their activities.
The consensus of the Task Force, in the absence of specific data in the literature, is that bed rest is contraindicated in subacute and chronic cases in diagnostic Categories 1, 2, and 3— i.e., not only must bed rest not be prescribed, but it must be stopped in patients still resting in bed at this stage.
The previous recommendations appear, however, to be inapplicable to cases in diagnostic Category 4, given the absence of specific data in the literature. Patients whose pain is intense enough to justify bed rest must be referred for a specialized back pain evaluation if they have not begun to progressively resume their daily activities after 10 days of strict bed rest (getting up only to go to the bathroom) and adequate pain therapy.
Because these recommendations stand accepted clinical practice guidelines on its head and necessitate significant changes in physicians’ attitudes toward common forms of low back pain, they are likely to be greeted with strong reservations. Their implementation clearly requires a major education campaign aimed at the entire range of health care professionals, including both physicians and their paramedical partners, as well as a major public education campaign through the mass media. The example of cardiologists’ recent promotion of the early resumption of physical activity after sudden heart attacks suggests that this approach is feasible and capable of success.
A number of difficulties specific to low back pain should, however, be borne in mind:
- • Recourse to specialists, systematic and early in myocardial infarction, is variable and late in cases of low back pain. The initial target group for the Task Force’s recommendations should be general practitioners, a considerably larger group than specialists.
- • Furthermore, medical consultation is highly variable in cases of acute low back pain, and several studies have demonstrated that it never exceeds one quarter to one third of cases. 81 It is therefore necessary to undertake a large-scale public-information campaign concerning the benign nature of most cases of low back pain, the fact that most cases resolve spontaneously, the value of early resumption of activity, and the ill effects of prolonged rest. Certain groups, particularly the Agency for Health Care Policy and Research (AHCPR) 11 have attempted to communicate this information to patients through the use of information sheets, but this has not been very effective. The value of having paramedical partners provide patients with personalized information has been demonstrated, but this approach is time consuming and requires resources that are currently unavailable.
- • It is widely accepted that “chronic low back pain” exacts a high psychological toll. Low back pain causes patients to question their future and raises fears about incapacitating neurologic complications, both of which encourage patients to rest as long as the pain persists. It is not easy to persuade patients that their pain does not reflect a serious condition or that maintenance of their activities will not increase the risk of complications.
- • Because of the undeniable analgesic effect of rest, patients are also likely to greet these recommendations with some skepticism. The results in the studies reviewed here clearly demonstrated that patients who were advised not to rest nevertheless rested for a few days.
For these reasons, the Task Force considers that rest should be advised against but neither forbidden nor recommended. When patients rest, every effort should be made to ensure that it is of as short a duration as possible. Furthermore, in cases of low back pain without objective signs of radiculopathy (diagnostic Categories 1 to 3) , patients must be strongly encouraged to maintain or resume their normal activities, as far as pain allows.
None of the studies specifically examined low back pain with sciatica, and it is unclear whether the results observed in low back pain without sciatica are applicable to cases in which sciatica is present, where the prognosis is generally poorer (diagnostic Category 4). Bed rest appears to be an acceptable treatment course in some cases of severe low back pain with sciatica, in that it seems likely to lead to improvement when combined with appropriate medication that provides symptomatic relief. However, it now appears futile to prolong rest beyond 10 days in the absence of improvement. This recommendation is the consensus view of the Task Force. It does not exclude the implementation of a conservative treatment regimen for considerably longer periods in cases of progressive improvement and appears to correspond to the usual practice when no improvement is evident. For diagnostic Category 4, given the absence of specific data in the literature, maintenance or progressive resumption of activities of daily living is authorized in acute and subacute cases and is recommended in chronic cases.
Despite the wide range of available exercise techniques and the fact that most of them have not been validated, exercise is still widely prescribed for low back pain, with and without sciatica. Several studies have demonstrated the very significant role of physiotherapeutic intervention in the management of acute low back pain. 62
The Task Force found no evidence that any exercise technique has therapeutic value in the treatment of acute cases of low back pain (duration of less than 1 week). It therefore considers the prescription of active physical exercise or restoration to be contraindicatedin the first week in all acute cases of low back pain (diagnostic Categories 1, 2, 3, and 4) in adults. This recommendation is clearly likely to meet with some opposition from several professional groups. A possible solution to this problem may be to limit reimbursement for care of this kind.
Results in one study have demonstrated the effectiveness of active management (a graded activity program) in treating cases of subacute low back pain (lasting between 4 and 12 weeks), and results in two studies have demonstrated the effectiveness of active re-education (therapeutic exercises) in the treatment of intermittent low back pain. It is therefore recommended that patients who have subacute intermittent or recurrent subacute low back pain be encouraged to follow an active exercise program. This recommendation reflects the fact that the risk of chronicity increases very rapidly in the first weeks of the episode of back pain.
Most studies conclude that active physical activity is a valuable therapeutic approach to chronic low back pain (pain lasting more than 12 weeks), even if there is no consensus on the specific technique, intensity, or active intervention. The Task Force therefore considers that there is sufficient scientific evidence to recommend that patients who have chronic low back pain perform physical, therapeutic, or recreational exercises, keeping in mind that no specific active technique or method is superior to another. Implementation of this recommendation should not be problematic, because it is current practice.
The Task Force is unable to recommend a specific physiotherapeutic technique, even though some techniques have been assessed scientifically. It appears that the key to success is physical activity itself—i.e., activity of any form—rather than any specific activity. The Task Force’s recommendation that there is scientific evidence in favor of programs combining strength training, stretching, and fitness is likely to cause a rethinking of widespread habits and convictions, and there may be some resistance to the implementation of such programs. This therapeutic approach must be based on a medical assessment performed by a competent professional and on the evaluation of the patient’s compliance with the prescribed course of action. Strong communication and collaboration between the referring physician and therapists is also of key importance. The same goal must be communicated to the patient to avoid confusion. In the current state of affairs, these conditions are not always satisfied, and occupational health insurance systems could play an important role in improving the quality and performance of prescribed treatment.
The Task Force’s recommendation concerning occupational activity—that except in cases of acute low back pain, the recommendations concerning activities of daily living also appear applicable to return to work, because occupational activities (physical workload) are a subset of activity in its most restrictive sense—implies that patients in all diagnostic groups should maintain or resume their work activities as far as the pain allows. Implementation of this recommendation should not be problematic, as long as the various stakeholders are convinced of the necessity of minimizing the duration of work absence (the chances of a timely return to work decline as the duration of work absence increases), and there are no deleterious effects of early return to work. The Task Force believed that should be the case if the physical demands of occupational activities do not exceed those of activities of daily living. In cases of acute low back pain, however, the absence of scientific evidence leads the Task Force to authorize rather than recommend return to work.
The significant effect of nonphysical factors such as the nature of insurance regimens (both public- and private-sector), workers’ compensation legislation, and labor relations on the return to work should not be ignored. Results in several studies have demonstrated the importance of these factors in the development of chronic low back pain. 107 Currently, they are too often neglected, and significant efforts should be expended to persuade the principal medical and social stakeholders of their importance.
When patients’ return to work depends on modification of their work or workstation, attending physicians should contact the occupational physician or case manager, and this contact should be regular. It is regrettable that patients’ evolution toward the end of the subacute stage should occur in the absence of communication between health and workplace stakeholders. The Task Force emphasizes the importance of establishing the return of their patients to regular occupational activities as quickly as possible as a therapeutic goal.
When, after 2 or 3 moths of treatment, a patient continues to experience problems adapting to occupational activities, physicians should alert the worker’s occupational physician or case manager, if not initiate occupational retraining. This recommendation is yet another reflection of the necessity of minimizing the duration of work absence, to avoid compromising the probability of returning to work. These steps should be taken as early as possible, in contrast to the current practice. It is important for all stakeholders to understand the need to address the occupational future of patients earlier than is often the case currently: The probability of returning to work is only approximately 50% after 6 months of work absence and is only approximately 30% after an absence of 1 year.
Priorities for Research
- • Evaluate the effect of rest and maintenance of activity in patients who have low back pain with sciatica (diagnostic Category 4).
- • Develop and evaluate functional scales with which to evaluate the therapeutic success of each type of activity.
- • Develop and evaluate strategies related to the prescription of activity to patients who have back pain and the evaluation of therapeutic results in these patients.
- • Evaluate strategies related to the maintenance of activity or the limitation of rest in the workplace.
- • Study the effectiveness of return to work as therapy (therapeutic return to work).
- • Evaluate acceptance among primary care physicians, physical therapists, and other health care providers of the Paris Task Force recommendations.
- • Evaluate the satisfaction and acceptance of the Paris Task Force recommendations by patients with acute and subacute low back pain.
Priorities for Clinical Practice
- • Include fundamental concepts related to the prescription of activity in medical school curricula and in continuing medical education programs.
- • Educate physiotherapists about the value of prescribing activity.
- • Include basic training in sports medicine in medical school curricula.
Lucien Abenhaim, Chair
For a long time I used to go to bed early.
The first sentence of Marcel Proust’s A la recherche du temps perdu (Remembrance of Things Past) could well have been spoken by many patients of that time, when medicine was powerless to prescribe anything but bed rest. Although interruption of activity was mandatory then, its prescription continued long after medicine had made great advances. Scientific medicine has led clinicians to question this essential principle in many cases (e.g., myocardial infarcts). Although strict bed rest was the accepted practice until the early 1970s, current practice is to encourage patients to get out of bed as soon as possible. A similar evolution of attitudes can be seen regarding hip replacement, cancer chemotherapy, and depression: Doing nothing is now considered unhealthy. Sign of the times? Or medical revolution?
Treatment of low back pain has so far resisted this tendency, because the role of activity in its treatment has been the object of three misunderstandings:
- • The first misunderstanding is related to the fact that certain activities (mainly occupational) are undeniably risk factors for low back pain and to the natural tendency to avoid activity once an episode of back pain has begun. Although re-exposure to the conditions that triggered the episode often causes pain that may sometimes be intolerable (reinforcing the idea that it is better to avoid the conditions altogether), conditions that cause back pain are not necessarily risk factors for chronicity.
- • The second misunderstanding stems from the association many people make between “sciatica”—i.e., low back pain accompanied by radicular symptoms and signs—and simple low back pain. Because rest is often indicated in the first group of patients, there has been a tendency to adopt the same approach in the second. Radiculopathy, however, accounts for a very low percentage (approximately 5%) of all cases of low back pain, and there is no longer any consensus on the existence of a continuum linking the two types of conditions.
- • The third misunderstanding arises from current approaches to pain management: Although it is common to neglect, if not disparage, specific and effective pain relief, it is considered important to avoid anything that might trigger pain. In the absence of specific pain relief, rest becomes the only possible choice—with unfortunate results.
These three misunderstandings are at the heart of an ambivalent attitude toward low back pain that is unaccompanied by neurologic symptoms or signs: Although it is commonly considered a condition without serious morbidity, rest (often bed rest) and various poorly evaluated treatments are often prescribed. A particularly pernicious side effect of this attitude is its reinforcement of the belief that this type of back pain is serious, although this is rarely the case. The ample evidence demonstrating inactivity to be a risk factor for both the incidence of back pain and its evolution to a chronic state clearly reveals the error of this approach.
Several expert groups have studied this question in recent years. The mid-1980s saw the almost simultaneous publication of the results of the Quebec Task Force on Activity-Related Spinal Disorders, 90 which questioned the value of the then-current practice of systematically prescribing rest, and the article of Deyo et al in The New England Journal of Medicine,29 which reported no increase in morbidity upon reducing the duration of prescribed rest from 7 to 2 days. These publications stimulated further work in this field. Although the literature base that existed at the time of the Quebec Task Force was very small, it had grown sufficiently by the 1990s to allow several task forces (including those in the United States, the United Kingdom, and New Zealand) to recommend including activity as part of the management of low back pain. No more systematic rest! As much activity as possible! are the current recommendations.
In practice, however, attitudinal change is a slow process, impeded not only by predictable intellectual inertia, but also by the skepticism, if not hostility, of some practitioners toward recommendations in favor of as rapid a return to activity as possible. The Task Force’s starting point, prompted by Bernard Avouac and explicitly formulated by Michel Rossignol, was that practitioners’ reticence is at least partially due to the absence of practical data concerning the implementation of activity-related recommendations. Although the popular “bed rest for all” is a simple enough guideline, “return to activity even if pain persists” raises many questions: which activity? for which patients? prescribed by whom? when? with what follow-up?
In this report, the Task Force attempts to provide at least partial answers, based on scientific data, to these questions. In the course of the analysis reported here, it became clear that the poor reception afforded previous groups’ recommendations may have reflected their lack of specificity. The Task Force has attempted to correct this shortcoming. Certain publications, although reviewed in detail by previous groups, were included in the present review, to extract all the data relevant to the formulation of practical recommendations for practitioners.
The term “activity” covers a wide variety of realities, which we have attempted to define under the following headings:
- • Mobility and activities of daily living
- • Recreational and sports-related activities
- • Occupational activities
In each case, we sought to identify the activities that could be performed by various types of patients, and most important, to provide operational definitions and concrete recommendations.
To maximize the precision of the recommendations, the Task Force slightly modified the Quebec Task Force’s clinical classification scheme. This allowed the Task Force to provide practitioners with a simple nosologic and semiologic tool with which to identify major pathologic presentations and to formulate recommendations on the role of activity in the treatment of each clinical entity.
Particular attention was paid to differentiating recommendations based on rigorous scientific studies from those reflecting consensus. Some of this report’s recommendations may well be invalidated by subsequent scientific studies; indeed, scientific validation of some of the recommendations, particularly those for which valid supporting data are not currently available, is desirable. This comment applies not only to the task force’s recommendations, but also, perhaps even more pointedly, to most current therapeutic approaches to the management of back pain, which have been adopted without the slightest supporting argument or controlled study. Only through scientific validation can the medical community hope to shake off the dogmas that, although the result of good intentions, may be doing more harm than good. It is for this reason that the Task Force’s methodology, discussed in the third section is of fundamental importance.
INTRODUCTION. ACTIVITY AND BACK PAIN
This introduction reviews the relation between activity and back pain of all kinds. This relation is complex, because activity has been variously considered to be a risk factor for back pain, a prognostic factor for back pain relapse, and a useful therapy in the treatment of back pain. 17,43,44,88 At first glance, it appears difficult to reconcile such a wide range of results, and no comprehensive review has in fact been published of the relation between activity and back pain. It therefore seemed essential to address the issue within a larger context than that of back pain and to discuss the specific relation between back pain and the following types of activities:
- • Mobility and activities of daily living
- • Recreational and sports-related activities
- • Occupational activities
Activity and Health
To understand the logic underlying the medical treatment of back pain and the problems associated with this treatment, it is useful to study both the influence of activity on human function and the social role of activity.
Activity in Human Function.
Activity is considered in all its forms, ranging from total inactivity to the hyperactivity practiced by professional athletes. The deleterious effects of both extremes on physical health are well known. Total inactivity (e.g., immobilization associated with bed rest) of even short duration (a few days) provokes a series of physiologic changes that lead to pathologic conditions affecting not only the musculoskeletal system but also the cardiovascular, neurologic, and cutaneous systems. This section is not concerned with the description of the deleterious effects of total inactivity. These effects have long been known, and this knowledge has led to significant changes in the practice of medicine in the second half of the 20th century. Regardless of the patient’s medical condition, complete bed rest should only be prescribed if absolutely necessary and, when prescribed, should be of as short a duration as possible. Application of these bed rest guidelines should help reduce the occurrence of side effects that are at least as serious as the treated condition.
Inactivity also exerts observable effects on the growth and development of children. The spinal column’s final shape and normal function is dependent on exposure to gravitational force and the maintenance of an upright posture. Prolonged bed rest during childhood hinders musculoskeletal development and leads to diminished neuromuscular control of posture and movement, with potentially permanent and catastrophic consequences on locomotion. Some of these effects are readily observable in adults who spend prolonged periods in outer space, free from gravitational force: Astronauts returning to Earth require a recovery period, the duration of which is proportional to the duration of their stay in space.
At the other end of the spectrum, physical hyperactivity, for example by professional athletes and artists, causes chronic alterations of loaded joints (including the back), which, in the long term lead to permanent physiologic, and eventually anatomic, changes. These effects are even more marked when strain is concentrated on a single joint. Pain is the main obstacle to the resumption and maintenance of activity in patients who have excessive joint strain.
Activity in Society.
The use of physical activity to maintain good health is a complex social phenomenon, with both personal and social components. Paffenbarger et al 84 observed a lower all-cause mortality rate among individuals practicing regular exercise. However, those who perceive their health status positively are precisely those most likely to exercise 8,32 —in other words, the least motivated individuals are the ones who may need exercise the most. In their literature review, Dishman et al 32 also noted that although the decision to begin an exercise program is motivated by the perceived beneficial health effects of exercise, program maintenance is a function of feelings of well-being and pleasure. These concepts have different connotations in different cultures and, in market economies, partially reflect the consumer behavior of individuals. The success of prescribed activity as a therapy depends not only on patients’ social context but also on their personal predispositions.
In summary, the type and intensity of activities determine whether they exert positive or negative effects on general health. Target clienteles for prescribed activity are the least likely to spontaneously initiate and maintain regular exercise programs. The prescription of activity should take into account patients’ personal characteristics as well as the characteristics of their social environment.
Activity and Back Pain
It is logical to suppose that excessive activity or inactivity not only exerts deleterious effects on general health but may also compromise back function. Campello et al 17 suggested that the relation between the level of activity and back pain follows a U-shaped curve—i.e., that too little or too much activity is equally hazardous for spinal health (Figure 1). However, there is only indirect evidence in the scientific literature on back pain to support this theory.
Mobility and Activities of Daily Living.
The first study of interest in this context is by Deyo et al, 29 who compared the effects of randomly prescribed bed rest (complete immobility) of 2 and 7 days’ duration to results in a group of ambulatory patients enrolled in a back pain treatment program. During the Task Force’s discussion of this study, it became apparent that it was often incorrectly cited in support of the contention that bed rest is detrimental to the treatment of back pain. Deyo et al actually concluded that if bed rest is indicated, it should be of as short a duration as possible.
No direct relation has been reported between back pain and either mobility-related activities or activities of daily living. These two types of activities have been considered indicators of functional status rather than risk factors in their own right. Four secondary analyses of the relation between back pain and mobility or activities of daily living, described later, illustrate this point.
The first study 71 was a cross-sectional study of patients who had chronic back pain. Activities such as bending over, walking, vacuuming, and remaining standing were reported to increase pain, whereas activities such as lying down and taking a hot bath were reported to decrease it. The correlation between reported pain and the level of activity was highly variable within the study population, and although the mean correlation was negative (r = −0.69;P < 0.01), pain and activity were found to be positively correlated (up to r = +0.45) in some subgroups. These results support the observation that perceived pain in the lumbar spine is poorly correlated to functional status. 29
In the second study, 119 a cross-sectional survey of the general population, a positive association was observed between back pain and activity among men. Activity was divided into three categories: sedentary (sitting or lying down), moderate (walking and light household activities), and vigorous (heavy housework). This classification system was vaguely defined and is not supported by any validated scale. Back pain was associated with intense activity among men aged 18 to 39 years and with moderate activity among men aged 40 to 64 years. Among women, the relation between activity and back pain differed in the various age strata.
Infante–Rivard and Lortie 51 measured the relation between pain during simple activities and the probability of a relapse in the following 6 months among patients who had followed a treatment program. Coste et al 20 measured the relation between back pain during simple activities at the onset of an acute episode of low back pain and the probability of returning to normal activity. In both cases, the presence of activity-related low back pain was a predictor of relapse and delayed resumption of normal activities. Figure 2 illustrates the results reported in these two studies for various activities. A relative risk greater than 1.0 indicates the existence of a positive association, with the length of the horizontal bars proportional to the margin of error of the effect estimate. These results indicate that low back pain that increases during simple activities is an indicator of prognostic severity.
In summary, there is no direct information on the relation between back pain and either mobility or activities of daily living. There is scientific evidence suggesting that the prognosis of recovering the full range of normal function is poor in patients in whom back pain inhibits the performance of basic activities of daily living, even if only in the acute phase.
Recreational and Sports-Related Activities.
For every study reporting an association between back pain and recreational or sports-related activities, there are many showing no association—e.g., Burton and Tillotson, 14 Kujala et al, 60 Rossignol et al, 97 and Mundt et al. 82 The upper portion of Figure 3 illustrates the results obtained by Mundt et al in a case–control study. In this graph, a relative risk less than 1.0 represents a preventive effect, whereas a relative risk greater than 1.0 represents a risk factor. Most of the relative risks are clustered around 1.0, with the variation largely caused by measurement errors.
These studies did not address the important issue of potential selection bias arising because the population of regular sport practitioners does not include individuals who have abandoned sports for health reasons. This selection phenomenon may bias the results toward the center of the figure, masking the potential risk associated with sports-related activity.
Campello et al 17 concluded that rigorous studies support the hypothesis that general exercise protects against back pain 7,16,108. Cady et al, 16 for example, studied the physical fitness of a cohort of firefighters, measured in terms of isometric strength, stamina, flexibility, blood pressure, and heart rate. In the 3 years after the beginning of the study, the incidence of reported back injuries was 7.3% in the least fit group, 3.2% in the intermediate group, and 0.8% in the fittest group. These results were not, however, controlled for factors such as age.
In a cohort study by Videman et al, 108 fewer episodes of back pain–related incapacity were observed in a group of male former Olympic athletes than in a control group composed of men who were medically fit for military service, matched for age and place of residence. These results are presented in the lower portion of Figure 3. Athletes were less likely to have back pain, regardless of the specific activity. It should be noted, however, that this group consisted of ex-athletes whose reported level of activity was no longer at competition level and that the interval between the athletes’ competitive period and the time of the study ranged from 10 to 60 years. Again, selection bias probably played a significant role in this study.
Interesting results were reported by Leino, 67 in a 10-year cohort study of male employees of a metalworking firm. An inverse linear relation was observed between the level of nonoccupational physical activity (mean duration of each activity multiplied by the estimated level of exertion) and the number of back-related symptoms, after controlling for age, activity, smoking, body weight index and stress-related symptoms. These results indicate that participation in regular physical activity and sports may prevent back pain. It is interesting to note that occupational and nonoccupational activities exerted equal but opposite effects—i.e., occupational activities constituted a risk factor for back pain. No such relation was observed among women in this study.
Campello et al 17 concluded that the ability of exercise programs to prevent back pain has not been demonstrated. A weakness often noted in these studies is the small population size. 66
In summary, studies on the relation between back pain and recreational and sports-related activities have produced results that are at least partially compatible with a U-shaped model of activity and health (Figure 1). Moreover, the apparently contradictory results obtained can be partially explained by the lack of uniformity in the measurement of physical activity and the wide range of populations studied (athletes and nonathletes).
Frank et al, 43,44 in their literature review on risk factors for back pain, concluded that the results of studies of acceptable quality indicate that biomechanical or physical factors contribute to the incidence of occupational back pain. They further noted the interdependence of so-called biomechanical factors and psychosocial factors specific to the work environment.
The role of work-related biomechanical risk factors is illustrated in Figure 4, using representative data drawn from the studies of Walsh et al 112 and Liira et al. 69 Risk factors include heavy work (digging, shoveling), driving vehicles, exposure to whole-body vibration, materials handling, and awkward trunk positions. These studies provide little practical help in identifying high-risk workstations, because they are cross-sectional in design, rely upon different definitions of biomechanical risk factors, and use different methods for workplace observation and data analysis and interpretation. 97 Currently, there is no validated method for the analysis and interpretation of data used to study the association between back pain among workers and biomechanical, organizational, and personal factors. 13
In summary, it has been established that working conditions can cause back pain in some workers. The data, however, are too macroscopic to be useful in the prevention of back pain, except in certain well-defined situations.
Prescription of Activity for Back Pain.
During the past 10 years, results in slightly more than a dozen experimental randomized studies have consistently demonstrated that the duration of back pain–related incapacity can be effectively reduced by a prescribed gradual return to normal activity. 17 The Task Force’s detailed analysis of these articles indicates that they generally provide inadequate descriptions of how activity is prescribed to patients who have back pain. It should also be noted that these studies are rarely reproducible, given their experimental nature and the uniqueness of the insurance programs and structure of health services in each country involved. Furthermore, treatment of back pain through return to work is an emerging and unevaluated therapeutic concept. 36,100
Conclusions Concerning the Relation Between Activity and Back Pain
Activity and back pain influence each other. Both total inactivity and some types of activity may cause back pain. Individuals who have back pain reduce their activity for periods the duration of which depends on the intensity of pain, the nature and intensity of their normal activities, and their psychosocial and occupational environments. The longer this period lasts, the greater the risk of the condition’s becoming chronic.
The prevailing medical approach to the treatment of back pain appears to consider a return to normal activities to be a more important clinical goal than pain relief. Results in experimental studies indicate that physicians can play an effective role in improving the functional status (mobility and activities of daily living) and psychosocial function of patients who have back pain, but not in accelerating their return to work. 74,96
Physicians are relatively ill prepared to prescribe activity to patients who have back pain, compared with other health conditions for which activity is a recommended therapeutic approach. The effective prescription of activity requires:
- • A better definition of activity
- • Formulation of detailed activity-specific clinical recommendations
- • Development of strategies and tools that allow physicians to promote activity through the application of their diagnostic, therapeutic, and evaluative skills
This report addresses the two first points.
HISTORICAL OVERVIEW OF RECOMMENDATIONS CONCERNING THE CLINICAL MANAGEMENT OF BACK PAIN
The various international updates to the Quebec Task Force on Activity-Related Spinal Disorders 90 have not significantly modified the conclusions of that report. This section presents the main recommendations of the Quebec Task Force and reviews the evolution of the situation between 1987 and 1997.
Quebec Task Force on Activity-Related Spinal Disorders
When the Quebec Task Force began its work in 1983, the North American view of back pain was that it was a benign health problem, rather more a nuisance than an important theoretical or clinical problem. However, the results reported by Abenhaim et al, 2 demonstrating that approximately one third of compensation costs for occupational accidents are directly related to back pain, and that 70% of compensation costs for back pain are accounted for by only 7% of cases (i.e., chronic cases), led to a significant shift in attitudes. This pattern of costs has since been confirmed in most industrialized countries.
The hallmark of the Quebec Task Force and of later task forces is a methodology integrating expert opinion with rigorous evaluation of scientific articles. Most articles reviewed by the Quebec Task Force did not meet this methodology’s evaluation criteria and were therefore rejected. One of the principal conclusions of the Quebec Task Force was that there was no strong scientific evidence supporting most of the common diagnostic and therapeutic methods used for the surgical and nonsurgical treatment of back pain.
The Quebec Task Force found such a wide range of diagnostic categories and clinical frameworks that it proposed simple—some might say simplistic—diagnostic categories based on the presence and duration of signs and symptoms. The classification system was a practical tool that allowed researchers to describe their inclusion and exclusion criteria in a common language.
The study by Deyo et al 29 on bed rest provided grist for the Quebec Task Force’s mill by demonstrating that, in the absence of “nonmechanical” disorders (e.g., tumor, infection, systemic inflammation, cauda equina syndrome, fracture), and even in the presence of persistent back pain, a return to normal activity should be attempted. This recommendation was greeted with some skepticism by both the medical community and the general public, and is still, more than 10 years later, regarded with some suspicion. Nevertheless, it was the recommendation most widely repeated by other task forces, and, visionary in its time, remains the main contribution of the Quebec Task Force.
The United States Agency for Health Care Policy and Research Task Force
Five years after the publication of the Quebec Task Force’s report, Bigos et al 9 published an update for the AHCPR, a government agency of the United States. After evaluating the scientific literature using methods similar to those of the Quebec Task Force, the American task force, composed of a great many consultants, made the following contributions:
- • Described the signs and symptoms (“red flags”) of back pain requiring urgent attention (as previously listed: tumors, systemic diseases, infections, cauda equina syndrome, fractures)
- • Summarized the scientific justification for diagnostic and therapeutic methods related to back pain
- • Proposed that patients who have benign back pain be evaluated by an interdisciplinary team between 4 and 6 weeks after stopping work
- • Reemphasized the importance of returning to normal activities, even in the presence of persistent pain
Because the task force considered back surgery a second-best option, to be resorted to only after a minimum of 4 weeks of back pain except in “urgent” cases, its recommendations were severely criticized in the United States, particularly by the associations of orthopedic surgeons and neurosurgeons, physiatrists, and physical therapists. 30 However, the United States government’s acceptance of these recommendations led many countries and professional associations to develop their own recommendations and guidelines that were very similar to the AHCPR guidelines concerning acute low back problems in adults.
United Kingdom and New Zealand Task Forces
In 1996, Waddell et al 110 reviewed the literature on acute low back pain for the Royal College of General Practitioners (United Kingdom) and published a series of recommendations concerning its clinical management. Their conclusions are similar to those of the two previous task forces, but include three new contributions:
- • Identification of risk factors for chronicity, including:
- • History of back pain
- • Cumulative work absence during the previous 12 months
- • Radiation of pain to the leg
- • Lasègue’s sign
- • Radicular signs
- • Reduced strength and stamina of trunk muscles
- • Poor physical fitness
- • Poor self-perceived state of health
- • Heavy smoking
- • Symptoms of depression or psychological stress
- • Low job satisfaction
- • Family or financial problems or alcoholism
- • Problematic medicolegal situation
- • A preliminary list of psychological and social factors to be included in a “biopsychosocial” assessment
- • The concept of “failure of first-line treatment”—i.e., of general practitioners—and the recommendation that patients be referred to specialists for a second opinion, and where necessary, rehabilitation.
The National Health Committee and the Accident Rehabilitation and Compensation Insurance Corporation of New Zealand reviewed these recommendations 55 and made two further contributions:
- • A tool, yet to be validated, with which to identify psychosocial aspects associated with back pain of 2 to 4 weeks’ duration (yellow flags)
- • The recommendation that the competency of clinicians to provide care should be examined and the possibility of referral considered in cases in which psychosocial factors contribute to back pain
The recommendations from the different task forces were translated and published in several countries, including The Netherlands, Israel, Australia, and Switzerland.
In all cases, the importance of abandoning a given treatment course in the absence of clinical results was emphasized. Moreover, the terms “failure” and “competency” were used freely in the documents addressed to clinicians. This aggressive tone is justified by the fact that in 5–10% of patients who have back pain, the pain becomes chronic, and they account for most social and health costs associated with back pain. In the task forces’ view, changing this situation requires management of the biologic, psychological, social, and occupational aspects of back pain by specialized and centralized resources.
The consensus of the various task forces examining the clinical management and treatment of benign back pain was that patients should resume their normal activities as quickly as possible; this view is supported by a growing number of rigorous studies. However, clinical application of the recommendations is problematic, given the current state of knowledge in this field. There appear to be four major obstacles:
- • The recommendations do not differentiate among the types of activity and in fact do not define activity at all. For instance, no task force has established whether resumption of occupational activities is at least as desirable as the resumption of recreational and sports-related activities.
- • The reports neither provide nor discuss clinically useful tools with which to evaluate functional capacity.
- • The reports recommend that attending physicians admit therapeutic failure early, to refer the patient to specialists expeditiously. This recommendation does not take into account the broader (i.e., other than strictly therapeutic) aspects of the physician–patient relationship, and could threaten continuity of care.
- • None of the reports describes the characteristics or clinical objectives of the specialists (either individual or in teams) to whom physicians should refer their patients. This “black box” recommendation is based on experiments conducted in sociodemographic and health care contexts that provide no generalizable data.
METHODOLOGY OF THE PARIS TASK FORCE
Reference Framework and Operational Principles
The Paris Task Force’s work is a direct result of the publication of American (AHCPR), 9 British (Royal College of Physicians), 110 and New Zealand (Accident Rehabilitation and Compensation Insurance Corporation) 55 recommendations concerning the management and treatment of back pain. These recommendations are restatements and updates of the recommendations of the Quebec Task Force on Activity-Related Spinal Disorders. 90 The fact that three members of the Task Force (Lucien Abenhaim, Margareta Nordin, Michel Rossignol) were members of at least one of the other task forces had two consequences in the work presented here: the Paris Task Force’s methodology is almost identical with that used by previous task forces, and the scope of the present work and the issues addressed are natural extensions of previous work. Specifically, the scope of the Paris Task Force’s work included both diagnostic and activity-related questions.
The most common forms of back pain were included, but vertebral fractures, tumors, cauda equina, and inflammatory and infectious diseases were excluded. The following classification system was used:
- •Category 1: Low back pain radiating no farther than the intergluteal fold, with no neurologic signs. Most back pain is in this category. Symptoms may be intermittent or constant, are of variable intensity, and are almost always aggravated by mechanical strain.
- •Category 2: Low back pain radiating no farther than the knee, with no neurologic signs. In this category, pain extending to the proximal portion of the leg may be neurogenic, but more probably arises in the deep structures of the spine (vertebrae and periarticular structures).
- •Category 3: Low back pain radiating beyond the knee, with no neurologic signs. In contrast to Category 2, pain in this category is probably neurogenic, although it may also arise from deep structures of the spine.
- •Category 4: Low back pain radiating to a precise and entire leg dermatome, with or without neurologic signs. This category includes classic radiculopathies such as sciatica, which although most commonly caused by disc herniation, may also result from other mechanical deformations of the spine.
This classification system differs from that of the Quebec Task Force, 90 although it adopts the same approach of classifying patients by symptoms rather than pathophysiologic status. For the purposes of this report, these diagnostic categories are flexible enough to be compatible with most diagnostic terms used in clinical practice.
Types of Activity.
The Task Force studied activities that are likely to be affected by back pain and to have an impact on patients’ normal function. Eight types of activity—related to mobility, transportation, daily living, sexual activity, sports and recreational activities, and occupation—were identified and subsequently grouped into three categories, each of which is discussed in its own section:
- • Activities of daily living (mobility, transportation, daily living, sexual activity)
- • Exercise (sports, recreation, alternative activities)
- • Occupational activities
Evaluation of Publications
The literature was searched through the Medline database (U. S., National Library of Medicine) for the period from January 1966 through July 1997, using all the key words derived from the diagnostic fields and types of activity described.
The resultant list was complemented by articles taken from the bibliographies of review articles. Furthermore, the personal knowledge of the literature of the members of the Task Force resulted in the inclusion of manuscripts and yet-unpublished research reports. Initial review of the abstracts resulted in a list of 1141 relevant articles published in English or French. The abstracts were then reviewed again, with particular attention to studies presenting original results.
This review process eliminated all but 150 articles, each of which was evaluated independently by two members of the Task Force using an analytical checklist specific to each type of study (see Appendix A), namely:
- • Controlled study with random allocation of participants (randomized trial)
- • Analytical study—either cohort, case–control, or cross-sectional—with a control group
- • Descriptive study without a control group; case series
The checklists included criteria related to the following basic aspects of epidemiologic methodology: population characteristics, exposure definition, definition of back pain, duration of follow-up, and statistical analysis. A training session at the beginning of the Task Force’s work helped members familiarize themselves with the checklist, and with the most common biases. Group exercises were conducted to ensure uniform interpretation of the criteria. Each of the 150 articles was presented to plenary sessions of the Task Force by two evaluators, and after discussion, was awarded two scores ranging from 1 (low) to 4 (high), one for methodologic rigor, the other for clinical significance. Some articles with a methodologic score less than 2 were retained because of their historical value or because they were the only source of data on a given topic. At the end of the exercise, 47 articles were considered valuable enough to form the basis for recommendations. The distribution of their scientific and clinical scores is presented in Table 2.
Formulation of Recommendations
The workload of the Paris Task Force was shared among three subcommittees, each responsible for one of the three main categories of activity: activities of daily living, exercise, and occupational activities. Each subcommittee studied the 47 articles selected, and extracted information relevant to their committee. To guide their work, a 3 × 4 grid was developed, based on the following three categories of duration of low back pain:
- • 0–4 weeks: acute low back pain
- • 4–12 weeks: subacute low back pain
- • >12 weeks: chronic low back pain
and the four diagnostic categories developed by the Task Force (see Diagnostic Fields).
A specific statement was developed for each cell of the resultant table, based on scientific evidence or, in its absence, the consensus of the members of the Task Force. Statements from the three committees concerning the appropriateness of each type of activity (rest, activities of daily living, exercise, and work) were combined into a summary table. The table is accompanied by an explanatory text summarizing the evidence from relevant references that formed the basis for the recommendations of the Paris Task Force.
The following nomenclature was used:
- • ++ Recommended: Activity should be prescribed.
- • + Authorized: Activity/rest should be neither actively prescribed nor forbidden. Prescriptions of activity or rest are acceptable, depending on circumstances.
- • − Contraindicated: Patients should be advised against exercise/rest.
- • 0 Not recommended: Not applicable or outside the scope of the Task Force’s mandate.
For scientific justification:
- • The quality and quantity of the scientific evidence evaluated by the Task Force leaves no doubt at this time of the scientific basis of the recommendation.
- • Consistent scientific data but no strong scientific proof support this recommendation. Interpretation of the articles is a significant factor, either because of methodologic problems in the studies or problems with generalization of results.
- • Despite the absence or paucity of acceptable scientific information, the Task Force was nevertheless able to achieve a consensus based on clinical experience and in-depth knowledge of the scientific literature.
MOBILITY AND ACTIVITIES OF DAILY LIVING
Mobility is the sum of all ambulatory states (such as walking, standing, sitting) and states of reduced mobility such as enforced bed rest. To define the degree of mobility that is normal for any given individual, a Medline search was first performed, using the key word “mobility.” A second search strategy consisted of reviewing studies that compared results in patients who engaged in physical exercise with a control group with normal mobility. None of those studies defined what constitutes normal activity. Studies of low back pain relying upon validated functional and quality-of-life indices were therefore analyzed to identify mobility-related activities, with an optimal functional score considered to correspond to normal activity. The Dallas, 64,78 Roland–Morris 93,94 (translated in French as the EIFEL scale), 21 Oswestry, 39 and Quebec Back Pain Disability 58 scales were selected.
The following mobility-related activities were retained for study: walking, sitting, standing, lying down, going up or down stairs, getting into a car, driving a car, and using public transport (Table 3). Analysis of the indices was complicated by the fact that some were purely qualitative (e.g., “walking like before”) or negative (e.g., “because of my back, I can only walk short distances”). For each activity, the indicator that best measured optimal performance was retained.
Using mobility-related terms from these scales, a graded scale of mobility-related activities that may be useful in managing a progressive return to normal activities was developed (Table 4).
Activities of Daily Living.
The term “activities of daily living” includes activities associated with personal care, eating, and normal daily household activities. The method used for determining normal mobility was used to develop a precise definition of normal daily activities. The following quality-of-life indices were used: Nottingham Health Profile 12, Health Assessment Questionnaire, 47 Sickness Impact Profile, 19 SF-36, 87 Roland–Morris 93,94 (translated in French as the EIFEL scale 21), Oswestry, 39 Quebec Back Pain Disability Scale, 58 and Dallas Pain Questionnaire. 64,78 As was the case for mobility, the articles in which these indices are used do not define “normality.” Furthermore, activities are usually described qualitatively according to the ability to perform a given movement or the degree of difficulty of the movement and only rarely according to quantitative parameters. The Task Force considered activities of daily living to be best measured by the following activities: leaning forward and bending over, kneeling and crouching, getting dressed and undressed, using the toilet, grooming, shopping for groceries, doing housework, picking up objects. The criteria for optimal performance of the activities of daily living are presented in Table 5.
Because the activities were never described quantitatively in the literature, it was impossible to develop a graded scale similar to that developed for mobility-related activities. However, the patient’s ability to perform a specific activity optimally can be scored simply as “yes” or “no,” and the degree of incapacity is proportional to the number of activities the patient is incapable of performing.
In conclusion, in the absence of definitions of mobility and activities of daily living in the literature, it was necessary to define these types of activity in relation to functional and quality-of-life indices. For each type of activity, optimal performance was defined; a graded scale of mobility was also developed. These classification systems may have diagnostic and prognostic value in the management of cases of low back pain and may be useful in planning a progressive return to normal activities.
Recommendations Concerning Mobility
For years, rest has been an essential therapeutic recommendation for patients with low back pain, with or without sciatica. This recommendation was based on experimental evidence indicating that pressure on the vertebral discs is lowest during bed rest. Furthermore, for some patients who are incapable of tolerating an upright position, at least at the onset of an episode of back pain, rest is clearly the only intervention that provides any measure of pain relief. This spectacular analgesic effect has led to the development of a sort of medical dogma concerning the prescription of rest in cases of low back pain, and even to its imposition upon patients who feel it unnecessary. It is only recently that the effect of rest on the evolution of low back pain has been objectively studied in clinical trials. Most of these have concluded that prolonged rest serves no purpose and delays return to work.
Six clinical trials of adequate methodologic rigor were identified in the search of the literature. In two of these the effects of systematically prescribed rest of different durations were compared. 28,103 In two others the effects of prescribing rest, exercise, or nothing were compared. 37,76 In one study, somewhat difficult to interpret, the effects of rest were compared with those of various other common therapies (manipulation, medication, and physiotherapy) and with those of a placebo 89. The last study examined a very specific group of patients, namely military recruits in training: Rest was prescribed in one group of recruits and prohibited in another. 110,115
Deyo et al 29 compared the effects of bed rest of 2 and 7 days’ duration in a group of 203 ambulatory patients who had acute (78% of cases) or chronic low back pain, with or without radiation. Several evaluation criteria were used. At the third week of the study, the only significant difference observed was a shorter duration of work absence in the 2-day group compared with the 7-day group (3.1 vs. 5.6 days). In both groups, the actual duration of rest differed from the recommended duration. In the final analysis, however, there was little absolute difference in the actual duration of rest (2.3 vs. 3.9 days) in the two groups, although the difference was statistically significant. There was no statistically significant difference in the other criteria, particularly in those related to functional capacity and the return to normal activities, at either 3 weeks or 3 months. In light of these results, it appears futile to prescribe more than 2 days of rest.
Szpalski and Hayez 103 studied the effects of rest of 3 and 7 days’ duration in a group of 51 selected patients (students and professionals). No difference in pain or functional status (measured by isokinetic methods) was observed between the two groups. Blue-collar workers were excluded from analysis in this study, because too many were lost to follow-up or considered 3 days of rest inadequate.
Evans et al 37 examined 252 patients who had low back pain with or without radiation to the legs; most of these were acute cases. Patients were randomly assigned to one of four treatment groups: rest (at least 4 days of bed rest); exercise and education; exercise, education, and rest; and control (analgesic medication, no specific instructions). All patients exhibited improvement. Neither rest nor exercise nor education appeared to influence recovery. It should be noted, however, that the mean duration of bed rest in the four groups varied from 5.02 days (no-rest group) to 8.89 days (rest group). Patients in the rest group took significantly longer to return to normal activities.
Malmivaara et al 76 examined 186 patients who had low back pain of less than 3 weeks’ duration (mean: 5 days), with or without radiation to the legs but without signs of neurologic deficit. Three treatments were compared: bed rest for 2 days, education and exercise, and maintenance of normal activities as far as pain allowed, but no bed rest. By the 3rd and 12th weeks of treatment, the maintenance group exhibited the greatest progress, measured by the duration and intensity of pain, lumbar flexion, work capacity, and duration of work absence.
Postacchini et al 89 compared five treatments in a group of 241 patients who had acute low back pain with (n = 83) or without (n = 158) sciatica: rest, manipulation, physiotherapy, medication, and a placebo. By the third week, manipulation was observed to be the most effective treatment; rest was less effective than manipulation, but more effective than the other three treatments. It should be noted that no statistical results were presented, the evaluation criterion was an unvalidated score composed of objective and subjective elements, and the effects of rest were only truly studied among 30 patients.
Wiesel et al 115 conducted a cohort study of 80 military recruits with acute low back pain with no radiation, who were randomly allocated either to bed rest in a hospital or to maintenance of basic activities (standing, walking, and so forth) and exclusion of heavy exercise. The bed rest group returned to normal activities significantly faster than the maintenance group (6.6 vs. 11.8 days). However, the initial comparability of the groups, duration of low back pain before the study, and randomization procedure were not described. Furthermore, the population studied is very unusual, and the results obtained cannot be extrapolated to the general public. This is the only study, however, in which rest was strictly enforced in one group and prohibited in the other.
To ensure that every participant is eligible for random inclusion in any treatment group, controlled studies of the effects of rest on low back pain must exclude patients in whom pain is so intense that it necessitates rest. This group of patients is thus never evaluated. In all but one of the studies described, some of the patients in the no-rest groups actually rested for some period. The only study in which rest was truly prohibited (and the prohibition enforced) was also the one in which the activity-maintenance group exhibited the poorest results. 110,115 However, none of the studies produced results demonstrating any advantage in prolonging rest beyond two or three days, and results in studies comparing the effects of prescribed rest and maintenance of normal activities as far as pain allows support the maintenance of activities.
None of the studies specifically examined low back pain radiating to the leg or low back pain with sciatica. It is unclear whether the results observed in low back pain without sciatica are applicable to cases in which sciatica is present and the prognosis is generally poorer. In studies that analyzed the effect of rest in subgroups composed of patients who had low back pain with sciatica, no difference in results was observed between these subpopulations and their parent populations.
For acute cases in diagnostic Categories 1, 2, and 3 (Table 1):
- •Bed rest must not be enforced or prescribed but is authorized if the pain indicates it.
- •Bed rest must be of as short a duration as possible and should be intermittent rather than continuous.
- •After 3 days of bed rest, patients must be strongly encouraged to progressively resume their activities.
For subacute and chronic cases in diagnostic Categories 1, 2, and 3:
- •Given the absence of specific data in the literature, the consensus view of the Task Force is that bed rest is contraindicated in these cases— i.e., bed rest must not only not be prescribed, but it must be stopped in patients still resting in bed at this stage.
For all cases in diagnostic Category 4:
- •Given the absence of specific data in the literature, the previous recommendations appear to be inapplicable.
- •Patients with pain intense enough to justify bed rest must be referred for specialized back pain evaluation if they have not begun to progressively resume their daily activities after 10 days of strict bed rest (getting up only to go to the bathroom) and adequate pain therapy.
Recommendations Concerning Activities of Daily Living
Four clinical trials of adequate methodologic rigor were identified in the search of the literature. In two of these, the objective was not to study the therapeutic efficacy of maintaining daily activities per se, but to examine the effect of such a course of treatment either in comparison or association with other therapies. The studies reviewed did not qualitatively or quantitatively define the specific activities of daily living that can be authorized in patients with back pain.
Turner et al 106 randomly allocated 96 patients who had chronic low back pain to one of four groups: behavioral therapy (which included encouragement to perform usual household activities), exercise, behavioral therapy and exercise, or control (waiting list). The only patients exhibiting significant improvement immediately after therapy, compared with the control group, were those in the behavioral therapy and exercise groups. At the 6- and 12-month follow-up visits, all patients receiving treatment had improved from their initial states but did not differ significantly from the control group.
Linton et al 72 studied the effects of specific activity training in a group of 198 patients who had back pain, all of whom had conventional therapy prescribed including maintenance of daily activities. All patients exhibited improvement after 3 weeks. Although specific activity training did not exert a significant effect globally, it reduced the duration of absence from work in patients with no history of back pain in the previous 2 years.
Indahl et al 50 studied 975 patients who had missed 8 to 12 weeks of work because of low back pain. The patients were randomly allocated to a control group receiving conventional treatment or to an intervention group. Patients in the intervention group received information, repeated after 3 and 12 months, on the benign nature of their condition and were encouraged from the beginning of the study to resume moderate activities. After 200 days of follow-up, significantly fewer patients in the intervention group were still absent from work (30%vs. 60%).
The study by Malmivaara et al, 76 in which activities of daily living were also examined, has been described in the section on mobility.
To ensure that every participant is eligible for random inclusion in any treatment group, controlled studies of the effects on low back pain of maintaining activities of daily living must exclude patients in whom pain is so intense that it necessitates rest. This group of patients is thus never evaluated. The nature of daily activities—particularly transportation (an indispensable requirement for most patients to return to work), sitting for prolonged periods, and sexual activities—is never described in these studies. However, there is no evidence from these studies that the evolution of acute or chronic low back pain is adversely affected by the maintenance of the activities of daily living. Furthermore, studies comparing the effects of prescribed rest with those of maintaining normal activities as far as pain allows favor the maintenance of activities.
None of the studies specifically examined low back pain radiating to the leg or low back pain with sciatica, and it is unclear whether the results observed in low back pain without sciatica are applicable in cases in which sciatica is present.
For all cases in diagnostic Categories 1, 2, and 3 (Table 1):
- •Patients must be strongly encouraged to maintain or resume their normal activities as far as the pain allows.
For all cases in diagnostic Category 4:
- •Given the absence of specific data in the literature, the maintenance or progressive resumption of activities of daily living is authorized in acute and subacute cases and is recommended in chronic cases.
The field of recreational and sports-related activities is vast and cannot be summarized in a few words. These activities are nevertheless critical to the Task Force’s work, and the following definitions are therefore proposed in an attempt to delimit and outline their essential components. The definitions are grouped into six sections, in increasing order of specificity:
- • Types of spinal movements
- • Nature of exercise
- • Types of exercise
- • Exercise parameters
- • Exercise evaluation techniques
- • Specific exercise techniques
Exercise can be defined as “a series of specific movements with the aim of training or developing the body by a routine practice or as physical training to promote good physical health.”113 There are many different types of exercise, 104 and although the most common exercises used in the treatment of low back pain are reviewed in this section, it should be borne in mind that this list is not comprehensive.
Types of Spinal Movements.
Movement is the result of the harmonious functioning of the sensory and motor systems in concert with the central and peripheral nervous systems. 114
Combined movement: Any combination of exercises or trunk movements, such as those defined in this section.
Extension: Dorsal exercises or trunk movements performed in the sagittal plane around a transverse axis.
Flexion: Anterior exercises or trunk movements performed in the sagittal plane around a transverse axis.
Lateral inclination: Exercises or trunk movements performed in the frontal plane, around a sagittal axis, to the left or right.
Rotation: Exercises or trunk movements performed in the transverse plane, around a longitudinal axis, to the left or right.
Nature of Exercise.
Aerobic exercise: Exercise occurring in the presence of molecular oxygen in the muscle.
Aerobic metabolism: Oxygen-dependent catabolism of energy substrates. Energy transfer results from electron transport and attendant oxidative phosphorylation. 86
Anaerobic exercise: Exercise occurring in the absence of molecular oxygen in the muscle.
Anaerobic exercise (anaerobic metabolism): Metabolism of energy substrates that does not involve oxygen. Energy transfer does not require oxygen. 86
Dynamic exercise: Joint movement resulting from muscular exertion. Dynamic exercise may be either concentric or eccentric. 59 During concentric exertion (in which a muscle’s origin and insertion are brought closer together), muscular force exceeds resistance, and the muscles shorten. In contrast, during eccentric exertion (in which the origin and insertion move away from each other) muscular force is less than resistance, and the muscle elongates. Muscle tension is greater during eccentric exertion than during isometric or concentric exertion. Complex movements are much more common during dynamic exertion than isolated movements. For example, during trunk flexion from the upright position, the spinal extensors perform eccentric exertion, whereas returning to an upright position requires these same muscles to perform concentric exertion.
Free-weight exercises: Combinations of eccentric and concentric exercises (see Dynamic exercise) in every plane and in all possible combinations of resistance, velocity, and acceleration. Dumbbells or other means of free weights are commonly used to progressively increase resistance and complexity.
Impact exercise: Exercise involving sudden and strong collisions.
Intermittent exercise: Alternation of periods of static or dynamic exercise, lasting from several seconds to several minutes, with rest periods. 57
Isokinetic exercise: Contractions performed at constant angular velocity. 59,116 Individuals are asked to perform a maximal voluntary contraction of a group of muscles using special equipment that uses a dynamometer to control angular velocity. Movement, either of a single joint or of a group of joints, is limited to a single plane.
Isoinertial exercise: Maximal or submaximal voluntary exercise against a constant external force, measured with an isoinertial dynamometer. 59,85 Movement may be in several planes simultaneously, resistance can be modified, and the velocity of movement is not controlled.
Isometric (static) exercise: Muscle contraction with posture or joint position maintained constant. Isometric exercise occurs when muscle tension equals external applied force; muscle length remains virtually constant. 59
Isotonic exercise: Exercise involving constant muscle contraction; also known as isoforce exercise. 59,116 Muscle tension is evaluated electromyographically or by other methods. This type of exercise is nonphysiologic and is usually only encountered in laboratory equipment.
Static exercise: See Isometric exercise
Types of Exercise.
Active exercise: Movement of a body segment as a result of voluntary contraction and/or relaxation of the muscles controlling a segment.
Active exercise against resistance: Voluntary movement against resistance.
Assisted active exercise: Movement of a body segment as a result of the voluntary contraction of muscles controlling the segment, assisted by a therapist, another individual, or a device or by other means.
Coordination exercise: Voluntary movement to reproduce a posture or one or more movements or exercises.
Corrective exercise: Clinical use of movements to maintain or restore normal function of diseased or injured tissues.
Equilibrium exercise: Movement or exercise performed to provide training in limb or trunk positioning or posture.
Free exercise: Active exercise with no support or aid from external force or resistance.
Graded exercise: Exercise the intensity (frequency and/or velocity), duration (time), or difficulty (resistance and complexity of movements) of which progressively increases.
Home exercise: Series of prescribed or learned therapeutic exercises, performed at home or at work, with or without the use of equipment, as part of an established program. 73,90
Passive exercise: Movement of a part of the body by another individual, a machine, or an external force or produced by voluntary effort of another limb of the patient’s body.
Power exercise: Power is equivalent to exercise per unit time, and integrates force and velocity (distance/time). Power exercises combine the effects of strength training and anaerobic training. 99
Quota exercise: A series of exercises defined by their nature (static/dynamic), intensity (frequency), duration (time), and difficulty (resistance and complexity of movements). The quotas become increasingly difficult. The goal of the program and the progression of quotas are established in consultation with the patient.
Repetitive exercise: Multiple series of a set number of the same exercises.
Therapeutic exercise: Exercise performed for the purposes of cure or restoration of function.
Duration of exercise or of the exercise program: The period during which the exercise or exercise program is performed, expressed in seconds, minutes, hours, weeks, months, or years. In the case of repetitive exercise, it may equal the patient’s lifetime. Evaluation of restoration programs depends in part on a knowledge of their nature and duration.
Exercise frequency: The mean number of exercises performed by a joint or body segment per unit of time.
Exercise intensity: The extent of maximal or submaximal exercise or exertion, expressed globally as the number of exercises per unit of time (frequency), or more specifically, as the number of repetitions per minute (RPM). It may also be expressed as a percentage of the maximum voluntary contraction (MVC) or the ratio of the maximum repetition to body weight. 46
Exercise Evaluation Techniques.
Evaluation of functional capacity: There is no generally accepted definition of the evaluation of functional capacity. The term is relatively new, and its definition varies depending on whether the evaluation is performed by insurance companies, care providers, or researchers. 40,52,65 In this context, “functional” is a qualitative term denoting a movement, series of movements, or completed task, and “capacity” refers to the quantification (from zero to maximal function) of the activity. This implies a definable concept with a measurable beginning, end, and result. “Evaluation” indicates a systematic approach that includes observation, data analysis, reasoning, and interpretation. More than mere recording, the evaluation process involves explicit evaluation of results and objective measurement of activity.
Fitness: Fitness may be expressed and used as a global indicator of physiologic well-being, and may integrate a wide variety of components—e.g., cardiovascular capacity, joint mobility, and muscle strength. Although there are no universally recognized indicators of fitness, there are many indicators specific to the various components of physical fitness. 15,16
Flexibility: Potential amplitude of movement of a joint or series of joints. 86
Incapacity rate: An indicator of a specific functional deficit. Currently, assessment of functional incapacity is based on the diagnosis of anatomic deficits or the summation of individual functional measures. 4 The incapacity–disability rate is a function of each country’s social security regimen.
Lifting test: A common clinical test to measure objectively the ability to return to work. 79 Patients’ lifting capacity is assessed in simulated manual materials handling that requires them to lift weights.
Muscle endurance: Capacity of a muscle or muscle group to contract submaximally during a given period. Usually measured in number of repetitions performed against 30–90% maximum voluntary resistance. 10,85,86 The stamina of trunk muscles is measured by having patients perform maximal or submaximal contractions of a muscle group against static or dynamic resistance. Several such tests are available for trunk muscles.
Muscle strength: Ability of a muscle or muscle group to perform a maximal voluntary effort. May be measured statically or dynamically with or without instrumentation. 26 Many different types of strength tests are available for the trunk muscles.
Position: Usually defined clinically as standing, seated, lying down, or other (e.g., standing with the trunk flexed forward and rotated). In the ergonomic literature, special systems have been developed for the observation of positions and postures. 75
Posture: Any major deviation from the upright anatomic position. 75
Specific Exercise Techniques.
Alexander technique: Developed in Australia in the early 1900s by Frederick Mathias Alexander, this technique emphasizes dynamic elements of postural organization during functional movements. Three techniques have been developed: awareness of a single internal and external sensory field, inhibition of ineffective postures, and constructive awareness that emphasizes process (continuous transitional information) rather than results and performance. The theoretical basis of this technique is the assumption that individuals can influence the integration of their voluntary motor responses and reflexes. The goal of the technique is to attain equilibrium and coordination while avoiding excessive muscular contraction. 6
Cyriax lordosis re-education: Exercises based on the theory that low back pain results from abnormal stretching of posterior muscle and aponeurotic structures. 24 McKenzie’s programs (described later) rekindled interest in lordosis exercises. 34
Exercise program in a specialized center: Series of therapeutic exercises and activities prescribed, directed, or supervised by health professionals. Patients usually perform these exercises only in a specialized center during a training period of predetermined duration and continue the program at home. In some cases, restoration may require prolonged treatment involving a specialized environment and interdisciplinary team. 9,90
Feldenkrais technique: The Feldenkrais technique was developed in Israel by the nuclear physicist Moshe Feldenkrais. 5 Its basic principle is that poor posture and harmful back movements originate in the brain. The technique concentrates on learning simple movements, and comprises didactic sessions termed “consciousness through movement,” and practical learning using functional integration.
Functional restoration: Structured interdisciplinary therapeutic program including assessment of the activities of daily living, occupational activities, therapeutic exercises, fitness, functional restoration, and the learning of a healthful lifestyle combined with psychological intervention. 9,49,80 This type of program is a very active daily program usually lasting up to 3 or 4 weeks.
Kendo: Japanese martial art in which competitors perform a series of combat movements using bamboo canes.
Lumbar locking in intermediate position: This method claims to relieve disc deterioration and instability as well as ligamentous pain in extreme positions. The technique relies on postural reflexes designed to adjust lower back posture automatically to a neutral intermediate position with no large-scale displacements.
McKenzie’s therapy: McKenzie’s therapy is based on the concept of centralization, 34 according to which the different pain patterns of patients who have low back pain result from mechanical disturbances. The nucleus pulposus, at the center of the intervertebral disks, is thought to be the anatomic structure that displaces the spine, and modification of the nucleus’s position is thought to explain different symptoms, with the intensity and location of symptoms correlated to spinal movements, position, and activities. This has led to the development of a classification system comprising four types of back pain of mechanical origin: postural syndrome, dysfunctional syndrome, disturbance syndrome, and mixed syndrome.
Modified activity: Modification of usual activities as far as pain allows—e.g., as a result of a patient’s requesting information from her or his physician or therapist concerning activities that can be performed without aggravating the condition. 11
Operant conditioning program: The theory underlying operant conditioning is that behavior can be modified by providing negative or positive reinforcement. Pain behavior, like all other behavior, can be modified. 41 Operant conditioning programs are based on the principle that patients understand that the exercises pose no danger to their backs. Patients receive continuous positive reinforcement, and their exercise and activity quotas are increased each week, session, or unit of time. The intensity of activity progressively increases to meet predetermined objectives (physical fitness, occupational, and social objectives, among others). 70,106
Proprioceptive postural training: Treatment of back pain through proprioceptive neuromuscular facilitation. Patients first learn how to detect the position of their lower back and go on to learn how to anticipate muscle contraction through a series of active stabilization exercises that involve lumbar pelvic positioning equilibrium reactions. 3,91
Spray and stretch: A group of therapies in which a cooling jet is used, including stretching and local treatment of certain muscles and the trigger zone responsible for myofascial syndrome.
Stretching: The stretching of muscles presumed to be too short or contracted. 56 Often included in restoration and rehabilitation programs for patients who have low back pain.
T’ai Chi Ch’uan: A martial art based on the principles of the I Ching and the philosophy of Lao Tzu. 68 T’ai Chi Ch’uan has undergone 19 generations of development, from the final years of the Ming dynasty (ca. 16th century) to today. Modern T’ai Chi is a series of continuous, balanced, and fluid movements performed with a straight trunk that acts as the axis of all movements. It dynamically imposes equilibrium while facilitating body positioning in the immediate environment. 118
Water (or aqua-) therapy: Exercises performed in a swimming pool, basin, or Hubbard’s tank. Water is used to reduce body weight (Archimedes’ principle) and increase the resistance to movement. The heat of the water also increases comfort and sedation.
Williams flexion exercise: Williams 117 developed the following theory of flexion exercises: “The sedentary life of most adults promotes weakening of the trunk flexors, especially the abdominal muscles, while their antagonists, the spinal muscles, become stronger through overuse.” This results in abdominal protrusion with displacement of body weight and the body’s center of gravity forward. This displacement is compensated for by lumbar hyperlordosis, which causes posterior displacement of the base of the thorax, and increases the strain on the posterior aspect of the lumbar spine and the lumbosacral structures. Injury may occur if a strong extension force is exerted while the lumbosacral spine is extended. Treatment should focus on reducing the extension of the lumbosacral spinal, displacing the center of gravity forward, and relieving posterior loading. 117 This is accomplished by establishing and maintaining an equilibrium between the opposing postural muscles—i.e., strengthening the trunk flexors and passive stretching of the tight trunk extensors.
Yoga: A system of exercises of Hindu origin that includes complex positions and postures and breath control. 102
Recommendation Concerning Exercises and Acute Low Back Pain
The exercises proposed in the literature are therapeutic and are based on a wide range of methods: isometric and dynamic muscle strengthening; flexion and extension; Williams’, Kendall’s, and McKenzie’s methods; stretching; and aerobic methods such as fitness, walking, and jogging; as well as stretching, stabilization, and other exercises of a less traditional nature.
The studies reviewed by the Task Force, all of which were randomized and controlled, rarely described exercise methods in detail. The most commonly recommended exercise regimen consisted of sessions of between 20 and 90 minutes’ duration practiced two to five times per week for several weeks, either at home or under the supervision of physiotherapists. The outcome variables included the evolution of pain, the range of motion of the spine, return to work, relapses, and various functional indices. Table 6 summarizes the different exercise programs reported in the scientific literature. There is conflicting evidence of the effectiveness of these methods, and none appears worthy of special recommendation.
Six articles discussing acute low back pain of no more than 7 days’ duration were identified. The results of theses analyses are presented in Table 7. Results in three studies, 37,38,76 in which rigorous methods were used, clearly demonstrate the ineffectiveness of prescribed exercise in the treatment of recent low back pain. In three other studies 27,42,101 exercise was reported to be somewhat effective, but only under certain conditions and in certain patient subgroups. Stankovic and Johnell 101 reported the McKenzie exercises yield better results than mini back-schools, Fordyce et al 42 reported an unspecified exercise program yields positive results after 9 months (but not 6 weeks), and Dettori et al 27 reported improvement in a group of young military personnel after 1 week of dynamic flexion–extension exercises, but no significant improvement thereafter.
The prescription of active physical exercise or re-education is contraindicated in the first week in all cases of acute low back pain (diagnostic Categories 1, 2, 3, and 4) . Dynamic, active exercises, in particular, are contraindicated.
Recommendations Concerning Exercises and Intermittent or Recurrent Subacute Low Back Pain
The search of the scientific literature identified two studies of the effect of activity on subacute low back pain and one study of the effect of activity on intermittent low back pain (Table 8); all three studies were conducted between 4 and 6 weeks after the onset of back pain.
Lindstrom et al 70 demonstrated the effectiveness of a graded activity program in cases of subacute low back pain in an occupational population. Hansen et al 48 demonstrated the effectiveness of active management of low back pain in selected subgroups of patients. Kellett et al 53 demonstrated the effectiveness of an active exercise program in cases of intermittent low back pain and provided a detailed description of the exercises.
Active exercise programs are recommended for patients who have intermittent or recurrent subacute low back pain of diagnostic Category 1, 2, or 3. Given the absence of specific data in the literature, these programs are authorized, but not recommended, for patients who have intermittent or recurrent subacute low back pain of diagnostic Category 4 (sciatica).
Recommendations Concerning Exercises and Chronic Low Back Pain
Ten studies, of rigorous design, in which random allocation was used were identified (Table 9). Patients in active-management programs were reported to fare better than control patients in seven of these. 33,45,55,61,77,92,106 Deyo et al 31 came to no conclusion concerning the value of physical activity. Only Coxhead et al 22 and Davies et al 25 observed no improvement in the active-management group.
There is sufficient scientific evidence to support the prescription of physical, therapeutic, or recreational exercise in cases of chronic low back pain of diagnostic Category 1, 2, or 3. Although no technique has been shown to be clearly superior, there is scientific evidence indicating that programs should combine strength training, stretching, and/or fitness. Given the absence of specific data in the literature, exercises of this kind are authorized, but not recommended, for patients who have intermittent or recurrent subacute low back pain of diagnostic Category 4 (sciatica).
Impairment, Activity Limitation, and Restriction in Employment Participation
The framework of reference for the Task Force’s discussions and recommendations concerning back pain and occupational activity is the new Second International Classification on Impairment, Disability and Handicap (ICIDH-2) in which the term “disability” is replaced by “activity” and the term “handicap” by “participation.” Activity limitations may be qualitative and quantitative and are assessed in terms of actual performance (execution of a task or activity). “Participation” refers to the experience of individuals with a health condition within a specific occupational context or environment.
Back Pain and Occupational Activity.
The epidemiologic literature on the natural history of back pain has largely restricted itself to activity limitation and work absence. 98 No satisfactory description of the natural history of back pain as a symptom (impairment) can be found in the abundant literature on back pain. The poor correlation repeatedly reported between back pain and occupational activity limitation may be partially because there is no appropriate paradigm. 28 Two observations illustrate this problem.
The first is that back pain impairment (without activity limitation) is highly prevalent in industry. For example, the point prevalence of back problems in a cohort of 269 assembly workers in an aircraft manufacturing plant who were observed for 12 months ranged from 7% to 40%, depending on how pain was defined. 97 Furthermore, the high prevalence of back pain observed in that cohort was not concentrated in a small number of workers but reflected a high turnover of back symptoms among the workers. This problem has remained unrecognized in the literature. Croft et al 23 reported that only 19% of actively employed workers with back pain had consulted a health practitioner during a 1-year period.
The second point is that back pain impairment leads to dynamic changes in worker–workplace interaction. In the same cohort of workers, predefined ergonomic risk factors (i.e., factors related to the physical environment) were not correlated with the prevalence of back pain 35 : Workers in “high risk” jobs had significantly less back pain than those in “low risk” jobs. Limited qualitative research revealed that workers in this plant could be reassigned to different types of jobs when they experienced back pain. The different jobs in the plant were thus associated not only with different types of ergonomic risk factors but also with different cohorts of workers with different histories of back pain. The conceptual framework that the Task Force proposes emphasizes the relation between back pain impairment and occupational activity limitation.
Conceptual Framework Linking Back Pain and Occupational Activity.
Biologic theories on the origin of back pain are insufficient to explain the complex interaction between back pain and functional outcomes in the workplace. Pain is the initiator of a series of psychosocial and occupational manifestations that have been linked together in the “biopsychosocial” model proposed by Waddell. 109 For the purposes of this discussion, it is useful to define “occupational back pain” in its broadest sense as back pain that occurs regardless of the employment status of the patient and regardless of whether it is due to occupational factors. Back pain and occupational activity may interact on three levels: regular activity, reduced activity, and interrupted activity (Figure 5).
Regular activity (i.e., impairment without activity limitation; left side of Figure 5) corresponds to a steady state of occupational function. This state is a balance between pain that is consistent with the pursuit of regular activity and daily fluctuation in job strains. Patients who have back pain may occasionally need medication, consult a health professional, or slightly change their normal routine, but there is no disruption of their regular occupational activity. Pain may be transient or a remnant of a past episode of back pain. If transient, the pain will completely resolve; if residual, recurrence can be expected. 2 Patients in this group include workers who have permanently changed their occupational activities as a result of a history of back pain.
In reduced occupational activity, regular occupational activity is disrupted but not completely interrupted (central part of Figure 5). This is an unstable state in which the patient can only continue to work if the work environment allows some flexibility in meeting work demands. It is by definition a transient state that either progresses to the interruption of activity or to a rehabilitative process that culminates in a return to either regular or modified activity.
Patients in the interrupted activity group are completely incapable of performing any occupational activity (right side of Figure 5). The duration of this state is variable and may be permanent, in which case patients must change occupation or remain inactive for a prolonged period. Patients who successfully change activities are no longer considered restricted and are reclassified as part of a new regular activity group, with or without impairment (left side of Figure 5).
The term participation restriction, used in the Second International Classification of Impairment, Disability, and Handicap (ICIDH-2), corresponds to this third stage, in which a prolonged interruption of activity has direct consequences on employment and employability. Accordingly, much epidemiologic research has attempted to identify prognostic factors for prolonged activity interruption 95. Reported prognostic factors include poor labor relations, the nature of the insurance regimen (workers’ compensation and others), 18,20 workers’ avoidance behavior (of the workplace), 111 and workers’ self-perceived disability. 83
Other prognostic factors stem from the interaction between workers with back pain and health care providers. Dramatization of the condition (labeling effect) 1,63 and promotion of rest 76 encourage patients to adopt a sick role and favor their entering and remaining in a state of interrupted activity. Thus, work accommodation on the part of employers and the insurers’ promotion of return to work can shorten the interruption of activity and eliminate barriers to participation.
In all three categories of occupational activity (regular, reduced, and interrupted), the relation between health care, the workplace environment, and the patient is iterative. Through trial and error, patients with back pain continue to seek pain relief and ways to accommodate the pain. The term “iterative” is used to reflect that the level of pain provides a direct feedback mechanism in response to health care and/or qualitative or quantitative changes in occupational activity.
In fact, workers with back pain can choose between two courses of action: seek medical attention to reduce their pain (upper part of Figure 5), or attempt to modify their activity in the workplace, to accommodate the pain (lower part of Figure 5). The involvement of insurance providers takes the decision out of the patient’s hands, at least in part, modifying this iterative process.
Back pain: Sensation of pain or discomfort in the back (shoulders to buttocks), with possible radiation. The relation between back pain and occupational activity takes three forms:
- •Back pain impairment: back pain that does not necessitate significant modification of normal occupational activities. May be transient or long term.
- •Activity limitation: quantitative or qualitative changes in occupational activity, compared with regular work. Temporary by definition.
- •Restricted participation: regular occupational activity that has been interrupted, leaving a patient unemployed. May be transient or long term.
These three categories are hierarchically dependent: It is possible to have back pain impairment without activity limitation, and to have activity limitation without restriction in participation. For instance, workers with a permanent activity limitation are not considered restricted in participation, within the framework of their redefined occupational activity.
Disability benefit: Financial compensation for health care or disruption of occupational activity, as part of a contract between an insured worker and an insurer (occupational or not). In many legislative regimens, employers have the obligation to provide occupational insurance for their employees. The benefit and rules of these insurance programs vary widely.
Employed person: A person who performs an occupational activity within the context of a binding contract with an employer.
Occupational activity: Any activity that is performed in expectation of a benefit, financial or other.
Regular occupational activity: Normal occupational activity planned or expected by an employer or the worker.
Rehabilitation: A multifaceted program designed to allow patients to return to their regular occupational activities.
Retraining: A program designed to teach patients skills that allow them to perform different occupational activities.
Return to work: Return to occupational activity after a temporary interruption. There are three types of return to work:
- •Return to regular occupational activity
- •Return to reduced occupational activity: return to regular occupational activity that is quantitatively or qualitatively reduced to accommodate workers with back pain who would otherwise be incapable of performing their regular activities.
- •Return to a different occupational activity: Accommodation of workers with back pain by returning them to a different occupational activity than the one that they would otherwise be incapable of performing. If temporary, the goal is identical with that of a return to reduced activity. If permanent, the new activity corresponds to a rehabilitative process that allows continued participation in employment.
Self-employed person: A person who accomplishes an occupational activity outside of the context of a binding contract with an employer (i.e., provides a commercial good or service).
Work absence: Temporary interruption of all occupational activity.
Workplace adaptation: Any change in the physical layout or manner in which work is organized, to prevent back pain from occurring or worsening.
Recommendations Concerning Occupational Activities
The therapeutic value of return to work is an emerging concept that should be followed closely in the coming years. However, currently available data are inadequate to serve as the basis for recommendations. Two studies on return to work as a therapy were brought to the attention of the Task Force. 36,100
Loisel et al 74 demonstrated that a return to regular work is the only worthwhile therapeutic objective. Returning workers to modified work allows them to resume their work after a back injury but does not lead to therapeutic success. In fact, some companies have used a return to modified work to hide cases when reporting compensation statistics. The same study also clearly demonstrated that therapeutic success, measured by return to regular work, is dependent on the efficacy of workplace interventions, with diagnostic and therapeutic clinical interventions and rehabilitation significantly less effective. In this study, the workplace interventions consisted of workplace meetings with supervisors to discuss modifications to the organization of the patients’ work. Attempts to modify the physical layout of workstations involved simple modifications. Although the extent to which these interventions affected work relations in this study is unclear, they no doubt had some effect.
In conclusion, the following aspects of workplace intervention favor workers’ return to their regular occupational activities:
- • Evaluation of workers’ physical capacity
- • Workstation assessment
- • Management of the return-to-work process by occupational physicians and the employer’s human resources department
- • Communication between workers and supervisors
- • Regular clinical follow-up during the adaptation period
For cases in diagnostic Categories 1, 2, and 3:
- •Except in cases of acute low back pain, the recommendations concerning activities of daily living also seem applicable to return to work, because occupational activities are a subset of a person’s activity in that term’s most restrictive sense (that of physical workload).
- •In cases of acute low back pain, the absence of scientific evidence leads the Task Force to authorize rather than recommend return to work.
For cases in diagnostic Category 4:
- •Given the absence of specific data in the literature, the maintenance of progressive resumption of occupational activities is authorized in acute and subacute cases and is recommended in chronic cases.
The members of the Task Force acknowledge and appreciate the excellent assistance rendered by Agence Nukleus (Paris, France) under the supervision of Dr. Bernard Savarieau, and particularly by Véronique Gordin, in the preparation of this monograph.
*See Appendix B for author affiliations.
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International Paris Task Force on Back Pain
Chair: Lucien Abenhaim, MD, ScD
Centre for Clinical Epidemiology and Community Studies, McGill University, Montreal, Canada
Scientific Secretary: Michel Rossignol, MD MSc
Centre for Clinical Epidemiology and Community Studies, McGill University and the Montreal Department of Public Health, Montreal, Quebec, Canada
Editorial Coordinator: Margareta Nordin, PhD
Occupational and Industrial Orthopaedic Center - Hospital for Joint Disease Orthopaedic Institute, New York University, New York, New York, U.S.A.
Editorial Coordinator Jean–Pierre Valat, MD, PhD
Hôpital Trousseau, Université de Tours, Tours, France
Task Force Members
Bernard Avouac, MD, Hôpital Henri Mondor, Creteil, France
Francis Blotman, MD, PhD, CHU Hôpital Lapeyronie, Montpellier, France
Jacques Charlot, MD, Centre Hospitalier Emile Roux, Limeil Brevannes, France
Renée Liliane Dreiser, MD, Chu Bichat, Paris, France
Erick Legrand, MD, Hôpital Hôtel Dieu, Angers, France
Sylvie Rozenberg, MD, Hôpital de la Pitié–Salpétrière, Paris, France
Philippe Vautravers, MD, PhD, Hôpital Hautepierre, Strasbourg, France
Task Force Support Group
Research Assistant: Maida Sewitch, PhD Candidate, Joint Department of Epidemiology, Biostatistics and Occupational Health Sciences, McGill University, Montreal, Quebec, Canada
Consultant: Ian Shrier, MD PhD
Centre for Clinical Epidemiology and Community Studies, McGill University, Montreal, Canada
Language Editor (English): Dawn Leger, PhD, Occupational and Industrial Orthopaedic Center, Hospital for Joint Disease Orthopaedic Institute, New York University Medical Center, New York, New York, U.S.A.
Centre for Clinical Epidemiology and Community Studies, McGill University, Montreal, Quebec, Canada