IOS Press
Return to work with chronic low back pain:
Using an evidence-based approach along with
the occupational therapy framework
Sonia Paquette
Downingtown, PA, USATel./Fax: +1 866 861 8 659; E-mail: [email protected]
Received 10 April 2007 Accepted 14 March 2008
Abstract. This paper will attempt to apply the occupational therapy framework [1] along with an evidence-based approach and an occupation-based intervention with a population of workers with chronic low back pain (CLBP) to help them return to work and maintain their work status. This paper will focus primarily on those clients with CLBP who still have a link to their employment but who do not perceive themselves as being capable to go back to their job despite conflicting opinions from other stakeholders (primary health care professionals, employer or insurer). They are being evaluated in occupational therapy shortly before return to work and followed until their optimal functional capacities are reached. This means that either all functional goals related to the actual physical demands of their job have been reached or that further treatment does not result in functional improvement. Keywords: Chronic low back pain, musculoskeletal, return to work, evidence-based, occupation-based, occupational therapy framework
1. Introduction 1.1. Clientele
Chronic low back pain (CLBP) is traditionally de-fined as low back pain with no known etiology and of over 12 weeks duration [20]. Health related care and work loss for people with chronic low back pain ac-count for 75–90% of the socio-economic cost of all low back pain cases.
Because of its high prevalence and cost, a consider-able amount of research has been done since the mid 80s in order to establish the predictors of work disabili-ty in this population [9]. Just recently, Kuijer et al. [20] systematically reviewed randomized controlled trials (RCTs) and prognostic studies in an attempt to sum-marize this large body of evidence. Despite more than 100 identified predictors of disability [9], most studied either once or twice, and the hardship of reconciling different study designs and outcome measures, Kuijer,
Groothoff et al. found that only the person’s own ex-pectations of recovery constituted consistent evidence as a predictor of the final decision to return to work. This finding is echoed in many other research and re-view articles not included in the systematic rere-view [6, 10,17,28]. Limited evidence for duration of work dis-ability was found for a few factors including health transition score and own expectations associated with employer’s response [20]. A large body of conflicting evidence was also found, notably in terms of the work organization structure and physical demands. Howev-er, research studying these latter determinants are qual-itative in nature [22] and have not been included in such a systematic review of the quantitative literature.
Return-to-work is often considered the ultimate lev-el of functional status as wlev-ell as the end of economic loss for all stakeholders involved. It is also commonly equated with recovery [11,26]. However, Baldwin et al. (1996; as cited in Ferguson et al. [11]) established that around 60% of workers discharged from
cal/therapeutic care when returning to work experi-enced further work disability. Not only the human cost of suffering and loss is great, but the financial burden of a re-injury is usually larger than the initial injury [11]. Baldwin et al. (as cited Dionne et al. [7]) suggested that return to work should be stratified to include functional levels ranging from returning to work with no or very little functional limitations and doing the former or a similarly demanding job, to return to only part of the former job duties with functional limitations. Fergu-son et al. support this view in proposing that return to work should not be equated with recovery: clients who return to work after an injury to their back may have to receive medical and/or rehabilitative treatment even after full return to work has occurred. Injured work-ers can be at work but unable to fully perform their functions. This is referred to as “presenteeism” [14]. Because physical recovery is embedded in complicated ways in the workplace processes, practices and social organization, return-to-work extends beyond managing physical function to the beliefs, roles, and perceptions of many players including the worker, the insurer and the employer [3,22].
Occupational therapists are health professionals who use meaningful activities as a means and as an end to treatment. Their role is to assist people to return to meaningful occupations in order to promote health. Baril et al. [4] found that becoming totally disabled after a compensated musculoskeletal disorder had a negative effect on a person’s quality of life including his finan-cial, mental and physical health. Despite this finding, it may be difficult to address a therapeutic return-to-work goal in a client-centered practice framework when the client’s targeted goals do not include return to work. It may also be difficult to devise a successful return to work when the match of the available job demands with the client’s capacities is questionable: in this case, it causes discrepancy with our goals of facilitating health. How can we ensure that the participation of this kind of client in work occupations contribute to their health and wellbeing?
This paper will attempt to apply the occupational therapy framework [1] along with an evidence-based approach and an occupation-based intervention with a population of workers with CLBP to help them return to work and maintain their work status. This work will focus primarily on those clients with CLBP who still have a link to their employment but who do not per-ceive themselves as being capable to go back to their job despite conflicting opinions from other stakehold-ers (primary health care professionals, employer or
in-surer). They are being evaluated in occupational thera-py shortly before return to work and followed until their optimal functional capacities are reached (i.e. a perfor-mance plateau is attained in the job capacities target-ed by therapy or no further improvement in functional capacities despite therapy).
2. Occupational profile 2.1. Who is the client?
CLBP is defined as low back pain with no known etiology and of over 12 weeks duration. Because of the pathology, associated pain, kinematic changes (i.e. change in the way muscles are recruited in the back), psychosocial factors (e.g. fear of reinjury) and other symptoms and signs associated with the CLBP, the clients targeted by this paper have difficulty completing their work tasks, or return-to-work is pending an inter-vention in occupational therapy. Clients usually present difficulties doing other non work-related tasks, of have completely relinquished them to keep their residual ca-pacities available for their working time window.
2.2. Why is the client seeking services?
More often than not, clients are receiving occupa-tional therapy services because their insurance carri-er, employer or primary care health professional have asked them to. They may be totally off work or are back to work in a modified duty job. As a rule, in this paper, the goal of the intervention is suggested by the referring agent as helping clients to get back to work in their former tasks, as quickly as possible.
2.3. What occupations and activities are successful or are causing problems?
With this clientele, activities involving awkward pos-tures (such as bending, twisting), standing or sitting for prolonged periods, whole-body vibration, manually handling materials (such as lifting or lowering weights), forceful movements ( such as pushing, pulling, work-ing with hands at or above shoulder level or without support, maneuver pedals with lower extremity, stand-ing on an unstable platform) are known to trigger or aggravate a pre-existing back disorder [8,21,30]. De-pending on the individual’s pathology and on their par-ticular signs and symptoms some tasks are more diffi-cult than others. For instance, one person might find it
difficult to stay seated for more than 20 minutes while another person can not walk for more than a few feet at a time. These functional components further impede the person’s participation in different occupations or activities, such as sitting to watch a movie, to work at their desk or to walk fast and with sudden stop-and-go as part of their work on a busy nursing unit. Depending on the types of occupations in which these people used to engage before their injury, and the signs and symp-toms they are currently presenting, their back injury will impact them differently.
2.4. What contexts support or inhibit desired outcomes?
Research tells us that a person’s own expectations re-garding their eventual return to work or recovery is the single most powerful predictor factor for actual return to work [6,10,12,17,20,28]. But what does influence this perception? One hypothesis is that other factors, recognized in the literature as possible predictors of work absence, (such as high job demands, unavailabili-ty of light duunavailabili-ty, high pain intensiunavailabili-ty and long duration of work absence) [9], may be impacting this perception. Schultz et al. suggest that the worker’s motivation to return to work depends on the relative value placed on work versus the cost associated with dealing with the pain inherent to returning to a more active lifestyle. They also conclude that the causes for work absence are “far more complex, multifactorial and individualized than reasons for return to work” [28, p. 83]. Fisher [12] notes: “therapists report that achieving changes in both work and non-work roles facilitates clients beginning to see themselves as employable for the first time since their injury” (p. 29). Qualitative research has given us some empirical indicators of return to work delay. These indicators include the worker’s perception of in-sufficient care or incomplete medical investigation, of receiving the wrong treatment, of having a major in-jury, of judging the work equipment as unsuitable or of perceiving the work demands as not matching their capacities [9].
A recent systematic review of randomized controlled trials (RCTs) by Schonstein et al. [27] identified that using physical conditioning, performing some kind of ergonomic interventions1at the workplace and adding a cognitive-behavioral approach2to a non-clinic based
1Undefined as to the content, quantity and goals. 2Idem.
treatment were the most effective approaches to help injured workers return to work. This suggests that be-sides the client’s expectations regarding their eventual return to work, their fitness level, work structure and organization, as well as belief system, may be targets for therapy goals in order to facilitate return to work.
An even more recent systematic review of the quan-titative literature about return to work (RTW) inter-ventions established that there was “strong evidence that work disability duration is significantly reduced by work accommodation offers and contact between healthcare provider and workplace; and moderate evi-dence that it is reduced by interventions which include early contact with worker by workplace, ergonomic work site visits, and presence of a RTW coordina-tor” [13, p. 607].
2.5. What are the client’s occupational history, priorities and targeted outcomes?
Particular occupational histories, priorities and tar-geted outcomes depend on the individual clients. Al-though most clients referred to occupational therapy have physically demanding jobs, they range from being blue collar workers to CEO’s of companies, from being single with no children to being the parent of preschool-ers. Their priorities and targeted outcomes depend on their work and personal histories, their values as well as their needs.
3. Occupational profile analysis
As mentioned before, three systematic reviews of the literature [13,20,27] come to the same conclusion as to what are the predictors of prolonged absence from work from an evidence-based point of view. In the fol-lowing table, on the left column, these predictors are worded similarly to how they appear in the systematic reviews. On the right column, these concepts are entan-gled with the occupational therapy framework vocabu-lary in order to establish the basis of the intervention. The occupational therapy framework is a mental model accepted by the AOTA in 2002 as a basis for interven-tions in occupational therapy. It suggests a “top-down” approach in which clients’s occupational profiles (their participation in their meaningful activities) is the tar-get of the intervention. In order to diagnose properly what are the causes of a sub-optimal life participation, the framework categorizes the possible causal factors in factors and sub-domains.
Table 1
Determinants/Predictors Domains and sub-domains of the OT framework
– Client’s expectations of returning to work – Particular belief system
Client factors (body functions: temperament and personality functions, energy and drive functions, experience of self and time functions, sensory functions and pain). The client’s
role has changed from being a worker to a non-worker. This is an area of performance
patterns.
– Fitness level Performance skills (motor skills: posture, mobility, coordination, strength, effort and ener-gy). The impaired fitness may be partly a consequence of impaired performance patterns, since the routine of a working adult usually involves getting up and moving around during the day, especially for people with more physically demanding work.
– Work organization and structure Context
– cultural: pain and disability as regarded in the client’s culture; work absence as regarded by the client’s family and work culture
– social: type of insurance, support system both at and off work, legal council present or not – spiritual: beliefs about work ethics and value
– temporal: age and gender at the time of injury, work stability, duration of disability, time before retirement
Activity demands
– space and objects characteristics: includes availability and pertinence of accommodations at the worksite.
– sequencing and timing of activities at work and outside, including availability of accom-modations for time (schedule or pace) and sequence.
– social demands: quality of relationship at and off work, type of work (e.g. customer or machine oriented)
– required body functions and structures Client factors
– body functions and structures (temperament and personality functions, energy and drive functions, experience of self and time functions, sensory functions and pain)
– Required actions at work and off work
Performance skills (motor and communication skills3) Performance patterns (roles, routines and habits)
All of these predictors are known to affect the client’s participation in at least one sub-domain of the areas of occupation (that is, work) but is most likely to affect at least one other sub-domain, such as social participa-tion, leisure or ADL’s. A major focus of the occupa-tional therapist will be to identify which sub-domains are significant to the individual and set the therapeutic goals upon them (Table 1).
4. Evaluation
The first step in establishing a plan of treatment to facilitate people’s participation in their life activities is to evaluate the extent and reasons of their participation withdrawal. Considering the importance of the
work-3To complicate matters further, some people with chronic low back pain (CLBP) develop a “communal coping style”, displayed in overly strong expressions of pain, including vocalizations and grimacing. This coping style, although adaptive in the acute phase of pain, becomes maladaptive when the condition becomes chronic [29].
er’s perception and belief system in his eventual return to work, the choice of of an evaluation tool that ad-dresses this issue in a comprehensive way, such as the Worker Role Interview, is paramount. This tool is com-prehensive, semi-structured, has been researched [12] and is based on a theoretical model that is taught in most occupational therapy curriculum in North Amer-ica. It would also be important to address the fitness level of the person as it relates to work demands with a short form of a commercial functional capacity evalua-tion (FCE). It can be accomplished in less than an hour and still provides me with some quantitative data and objective measure of performance in a limited tempo-ral and spatial context. This short-form FCE has been researched and developed in an independent research facility [16]. FCEs have a notoriously low predictive value for work performance [15,18,23]. Therefore, re-sults of the FCEs should be usedit as a baseline measure and as a cue to facilitate choice of tasks to be included in the client’s gradual return to work program. Indeed, as mentioned earlier, the clientele targeted by this pa-per is workers who do not consider themselves capable
of returning to work despite conflicting opinions from other stakeholders. Therefore, since a job is readily available, a job analysis of the demands will provide part of the goals of the rehabilitation program.
As it is for predictive validity of FCE results used alone to determine return-to-work readiness, research on FCEs results responsiveness to the client’s actual change in condition is complicated by the choice of appropriate external criterion and the natural change in performance over the course of time [19], the results of repeated FCEs should be used to monitor and compare them to the workers’s perception of their actual change in functional status over the course of the return-to-work program. Knowing that there is weak correlation between worker’s self-report and FCE results [6] the re-sults should not be considered an objective evidence of discrepancy between “real” capacities and the workers’ perceptions of their capacity, but as a mean to establish achievable fitness goals.
Because participation in meaningful activities is not restricted to work, occupational therapy intervention usually also researches the effect of the back injury in other areas of performance, particularly in activities of daily living, using the Oswestry Disability Index (ODI). This tool assesses pain intensity and disability caused by low back pain in nine different activities of daily living. Pain intensity can and should be measured as a separate measure with a Pain Numerical Rating Scale. Since so much of an occupational profile dysfunc-tion rests within the person’s context, the importance of assessing the work organization and structure in which the client has or will be getting back to work cannot be overstated. Part of the Worker Role Interview can be used to assess the client’s perception of the “wel-coming structure” of the organization. Although this concept has not been defined as such in the literature, there appears to be researchers’ consensus that one of the strongest predictor of return-to-work is the employ-er’s interest, values and input to facilitate the return-to-work process. Using a quantitative/qualitative method for assessing the work physical demand highlights one of the employer’s welcoming structure’s components. Using the Tools for modified work (TMW) has the ad-vantage of not only pertaining to the external physical demands but to how much these demands are perceived by the worker. Since the TMW requires the presence of both an employer’s representative and the worker to be completed, it serves as a stepping stone for a semi-structured interview to address issues with the employ-ers, such as possibilities for accommodations (modi-fied and graduated work), flexibility in the work,
pro-duction quotas, employer-employee relationship histo-ry and the like.
Finally, the use of the Work Role Functioning ques-tionnaire (WRF) to establish a baseline to determine where the workers is independent to perform their com-plete job duties at the end of the rehabilitation program. Table 2 highlights the construct to be evaluated, the tools mentioned in the above-paragraph for evaluating these constructs along with their references and psy-chometric characteristics.
The constructs and the tools suggested in this pa-per were selected after reading numerous studies and selecting the following papers. They are presented in Table 3 according to the evidence-based practice hier-archy proposed by Sackett et al.
5. Intervention
The evaluation part of an occupational treatment al-lows one to establish intervention goals and start inter-vening with the clients. Intervention follows the partic-ular findings of the client’s evaluation. Context is cru-cial in occupational therapy and increases the efficacy of intervention [24]. This is echoed by the evidence that return-to-work programs based at the worksite are more effective than those clinic-based [27]. Therefore, based on the current research, best practice interven-tions should take place at the worksite whenever pos-sible. Intervention that consists in developing a grad-uated return-to-work program using regular and mod-ified duties in order to reach the optimal goal of re-turning clients to work full-time in their regular duties, with limited functional limitations, both at work and at home. The results of the evaluation should be com-pared to create an individualized graded treatment plan for clients with CLBP, using their work tasks and their occupational choices at home as therapeutic modalities.
5.1. Therapeutic approaches
In the medical model, therapeutic intervention is ap-plied to the clients themselves. In the occupational therapy framework, this direct application of therapy would address either the client factors or their perfor-mance skills. While it is not common in medicine, therapeutic goals addressing the clients’ context, per-formance patterns and activity demands, which are not client factors under the occupational therapy frame-work, are prominent in rehabilitation and especially in occupational therapy.
Table 2
Tools: reliability and validity
Evaluated construct Tool Reliability Validity
Client’s expectations of return-ing to work, values, interests, roles, habits and social and physical environment
The Worker Role Interview (WRI)
WRI: high test-retest reliability: 0.86 to 0.94 with a total value of 0.95 and interrater reliability for six content areas ranged from 0.46 to 0.92 with a total value of 0.81 [5]
Azhar (master’s thesis, unavailable) studied the WRI along with demo-graphic data and found some predic-tive value in the tool, more so than with the demographic data. It has not been compared to other predic-tors, however.
Pain intensity Pain numerical rating scale (PNRS)
Oswestry Disability Ques-tionnaire (see below)
PNRS: Excellent test-retest reliabil-ityr=0.96 and good construct va-lidity as compared with other mea-sures of pain intensity [9]
No data
Fitness level (work and func-tional capacities)
Short form FCE – (FL) floor to waist lift – (CR) crouching – (ST) standing
Short form FCE: no data Predictive validity Hazard rate ratios – FL: 0.64 (CI: 0.42–0.97) – CR: 0.59 (0.38–0.91) – ST: 0.68 (0.48–0.95)
[15] (as a predictor of duration of absence)
Oswestry Disability Ques-tionnaire (ODQ)
good test retest reliability (r=0.83) and internal consistency (Cronbach’sα=0.71) [9]
No data
Work organization WRI (see above) Tools for modified work (TMW)
TMW: No study TMW: No study, high face validity (Agence de d´eveloppement, 2005)
Work performance TMW (see above)
Work Role Functioning (WRF) (previously called WL-27)
Internal consistency 0.88–0.91; test-retest reliability, no data (B.C. Amick III, personal communica-tion [2])
Construct validity established
It is sometimes confusing to separate interventions at the client factor level or at the performance skill level. The separation may not be necessary: two or more approaches may be meshed in the same interac-tion with the client. The following are approaches pro-vided through the occupational therapy framework as applied to the clients described in this paper.
PREVENT DISABILITY and further injury
– By exploring the clients current capacities and
lim-its, matching the capacities with required physical demands, through instruction, demonstration of risk factors that could aggravate the current injury and by revising their occupational balance (client
factor, activity demands, performance patterns); – By establishing a therapeutic relationship with
clients to support and help problem-solve the inevitable inconsistencies in their performance, work demands, schedules, social demands or ex-pected physical requirements or other non-work
related functional problems (client factor,
perfor-mance patterns, context);
– By modifying work demands using modified tools
and changes in performance patterns (performance
patterns, performance skills and activity demands) – By educating the employer representatives, the
medical and other rehabilitation providers as well as the insurer about the rehabilitation process, keeping them informed of the progression of the rehabilitation plan, the progression of this partic-ular client’s work performance, and welcoming their input to facilitate the process (context)
MODIFY, COMPENSATE, ADAPT
– By compensating the residual lack of
perfor-mance skills and patterns in some work activities through tools, pacing or sequencing (activity
de-mands, context, performance patterns)
– By compensating difficulties encountered at
Table 3
Major papers reviewed with decreasing levels of evidence
Level of evidence Paper Findings
Systematic reviews of RCT Shonstein et al. [27] Physical conditioning, ergonomic interventions at the workplace and adding a cognitive-behavioral approach to a non-clinic based treatment are the most effective approaches to help injured workers return to work
Systematic review of RCTs and prognostic studies
Kuijer et al. [20] Only the client’s own expectations of recovery is a consistent predictor of return to work in all studies reviewed
Systematic review of observa-tional studies and below
Maceachen et al. [22] Strong evidence that work disability duration is significantly reduced by work accommodations offers and contact between healthcare provider and workplace
Observational prognostic study Baril and Berthelette [3] Presence of a modified duties position and a structured return to work program facilitates return to work among injured workers
Cohort data, experimental design Gross et al. [16] Use of a short form commercial FCE can provide useful information on the worker’s capacity to do the work when the work demands are known and mirrored by the three subtasks
Non systematic review of RCTs and observational studies
Durand et al. [9] Data on the Oswestry Disability Questionnaire and the pain numerical rating scale, empirical clues from therapists as to what facilitates or hinders return to work which are not research-based predictors of work disability Case report (interview with
therapists)
Fisher [12] The Worker Role Inventory content, description and its use in addressing a holistic view of the worker in a rehabilitation process
activities or modifying current occupational bal-ance (performbal-ance patterns).
– By educating the social environment including the
family, the employers and the insurer about the process and prognosis of the individual (context).
MAINTAIN work status
– By carefully monitoring the activity demands on
their work performance and functional capacities at home (activity demands, context).
– By exploring and mastering pain management
techniques (client factors)
RESTORE physical fitness levels (strength, coordination, aerobic capacity)
– By designing a fitness program using home-based
activities (client factors, activity demands,
perfor-mance patterns and skills)
– By gradually increasing the physical demands at
work through a return to work plan (client factors,
activity demands, performance patterns and skills)
5.2. Discharge planning
According to Portney and Watkins [25], the charac-teristics of responsiveness of a test can be considered a component of the test validity. Occupational thera-pists working with individuals with CLBP getting back to work can use the same tools for evaluation and for
discharge planning. Most tools used, except the short-form FCE and the PNRS, are based on the worker’s perception of his capacity to perform work-related and non work-related tasks, which is the most prominent predictor of return-to-work. The observation and anal-ysis of the actual performance of workers in their work context adds a strong component of validity to any in-tervention based on the results of this analysis. Using a non or semi-structured interview with the employer to determine their perception of the worker’s perfor-mance adds another validity component. Indeed, the employer is an important stakeholder who can facilitate or discourage the therapeutic interventions.
6. Conclusion
In this paper, an attempt was made to apply the occu-pational therapy framework with a clientele of workers with CLBP returning to work, based on the scientific evidence, using an occupation-based practice frame of reference and the author’s experience in this area of rehabilitation. Evaluation tools were chosen according to their relationship with predictors of RTW with this population. Research concludes that workers’ percep-tions of their capacity to work is the most prominent predictive factor for RTW. This perception appears to be determined by their beliefs, values, fitness level, ac-commodation possibilities at work and work physical and organizational demands. Intervention approaches
made at the worksite are encouraged as they tend to bear better outcomes. Whether it is because the need for learned skills carry over is decreased for clients, or because of the compound influence of client factors, performance skills and patterns as well as physical and organizational demands is yet to be found. Finally, by no longer considering the RTW outcomes as a dichoto-mous variable, but rather as a stratified variable based on the extent of residual capacities and incapacities, occupational therapy interventions can not only assist clients with CLBP increase their participation in life activities including work, but doing it while making sure it has an added benefit in their overall health and quality of life.
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