THE NATURAL HISTORY AND EFFICACY OF

TREATMENT OF CHRONIC PAIN ARISING FROM

MUSCULOSKELETAL INJURY

Eldon Tunks MD, Joan Crook RN PhD,

and Mikaela Crook LLB

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INTRODUCTION

Work injury and pain are costly. They exact a heavy toll upon workers financially,psychologically, physically and socially, and they consume considerable societal andemployer resources (Spitzer, 1987). In 1996, for example, the Ontario Workers’Compensation Board reported that 103,080 workers claimed a work-relatedinjury/disease for which time was lost. Approximately 31% of these claims wereassociated with an injury to the back (Workers’ Compensation Board of Ontario, 1996).Most, approximately three-quarters, workers who sustain a work-related back injuryreturn to work within two to three weeks (Spengler et al, 1986; Spitzer et al, 1987).About seven percent, however, do not return to work by 6 months and this minority ofclaimants consumes considerable resources. In fact, the research suggests that thisminority accounts for 75% of costs to the system, such as lost hours, indemnities, andcosts related to the use of health care services (Spitzer et al, 1987; Spengler et al, 1986;Snook, 1987; Webster and Snook, 1990; Volinn et al, 1988).

The personal, societal and industrial costs of pain-related occupational injury, and thedisproportionate costs of the minority of claimants, have engendered considerable interestin persistent pain and its effective and efficient treatment. This paper offers a criticalreview of the current understandings of persistent pain and current treatment modalities.Specifically, the objectives of this critical review are to: (a) describe and criticallyreview the natural history and current uni-modal and multi-modal therapies used in themanagement of chronic musculoskeletal pain; (b) assess which approaches in theliterature have been determined to be effective and efficacious through appropriate andrigorous research methods, and; (c) synthesize the research findings into a clear, concisesummary of the relative efficacy and effectiveness of each treatment modality.

In order to search for relevant publications, searches were performed in Medline/Pubmedand in the Cochrane Library. There was no specified time limit. Searches wereperformed with respect to clinical disorder, publication type, intervention type, and“related articles”. The categories for clinical disorder were; pain and chronic disease,back pain, neck pain, and cumulative trauma disorders. The categories for publicationtype were; meta-analysis, systematic review, RCT, follow-up studies, treatment outcomestudies, and practice guidelines. The categories for intervention type were; cognitivetherapy, combined modality therapy, multi-modal, manipulation, chiropractic, patienteducation, psychotherapy, behavior therapy, and cognitive therapy. The “related articles”option was chosen in Medline/Pubmed. Language choice was English.

While the main strategy was to retrieve quality systematic reviews and meta-analyses toperform a review of reviews, the literature on injection therapies for “myofascial pains”and soft tissue pain has only a few RCTs. Hence, these RCTs were used for the sectionon “injection therapies”.

The retrieved articles were handsearched for articles that may have been missed by thecomputer searches. Other experts were consulted for other articles that might have beenmissed.

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Inclusion criteria were systematic reviews or meta-analytic reviews of non-surgicaltreatment of non-malignant chronic musculoskeletal pain. Exclusion criteria werenarrative reviews, reviews that did not include either natural or clinical course, ortreatment. Some retrieved citations were rejected on the basis of published abstracts, anda few were rejected after the authors scanned the retrieved articles for inclusion criteria.

Meta-analytic and reviews were independently rated by the authors using the criteria ofOxman and Guyatt (1991). There was complete agreement in the ratings on three-pointscale of acceptable, borderline and unacceptable. RCTs were rated by one author usingthe criteria of Jadad et al. (1996). Author blinding was not used. Tables wereconstructed to summarize the significant findings from this review of reviews. Thesetables are presented in Appendix 1.

NATURAL HISTORY OF POST-TRAUMATIC MUSCULOSKELETAL PAIN

The temporal course of post-traumatic musculoskeletal pain has heretofore eludedcomprehensive conceptual description. The process of recovery and/or development ofdisability are understood, primarily, from two rather simplistic biomedical perspectives.

In the first biomedical perspective, illness is believed to be solely due to biologicalpathology (Leibowitz, 1991; Turk, 1991), and injury is understood as a linear sequencefrom casual factor, to pathology, to symptoms or manifestations (Haldeman, 1990).Symptoms and disability, according to this view, are directly related and proportionate tothe physical pathology (Waddell, 1987). Elimination of the pathological causes,accordingly, is assumed to lead to cure or improvement. In reality, however, apathological explanation of pain cannot be made in over 85% of work-related injurycases of low back pain (Spitzer et al, 1987), and, further, the explanation fails to predictdisability.

Another perspective on the process of recovery and the development of disability isgrounded in the assumption that wounds heal and do so according to a predictable timeline. According to this perspective, normal healing of damaged musculoskeletal soft-tissue follows a three stage process: inflammation, laying down of scar tissue, andremodeling of scar tissue (Caillet, 1988; Fess and Philips, 1987). The assumption thatwounds heal in this fashion and that any pain persisting past usual wound healing time is“chronic”, is convenient, but based on an arbitrary assumption that distinguishes complexphysiological, psychological, and functional phenomena on a unitary time dimension.The healing process can be affected by a number of mediating factors, such as systemicdisease. It is also thought that psychological reactions to injury can have physiologicaleffects on healing (Holden Lund, 1988), although “complementary healing” in acontrolled trial did not apparently improve wound healing (Wirth and Barrett, 1994).The downside of the wound healing model is the dismissal or suspicion of persistent painsufferers on grounds that the injury “ought to have healed by now”. Another downside isthe assumption that those who will recover will be a majority and will do so within the

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usual bracket of simple wound healing, and those who do not conform to the proposedtime-frame will be a simple minority who will become the long-term chronics.

Research to clarify the clinical course of post-traumatic musculoskeletal pain has beenundertaken. Early research seemed to offer a favorable prognosis for persistentmusculoskeletal pain. Panel studies of primary-care-based based samples, for example,suggested that 90% of patients seeking treatment for back pain will be pain free within 1month (Kelsey and White, 1980; Nachemson, 1985; Deyo and Tsui-Wu, 1987).Overestimation of favorable outcome within the early research may have been due, inpart, to the outcome variables examined and/or the study design employed. Certain typesof outcome measures, such as return-to-work (RTW), may reflect some but not all factorsneeded to evaluate outcome (Mitchell and Carmen, 1990; Butler et al, 1995). Further,retrospective research designs employed in much of the research, particularly in the studyof the evolution of back pain, can lead to overestimation of favorable outcome for oftenthe populations ultimately examined do not include those for whom prognosis is poor.Prospective studies are more revealing (Wahlgren et al, 1997; Crook et al, 1998, inpress). More recent research challenges the earlier findings of favorable outcome.

Recent work by Baldwin et al (1996) highlights the “fallacy” of favorable outcomecreated by use of initial return-to-work as sole outcome measure. First return-to-workafter injury marks a return to stable employment for less than 40% of injured workers. If,as Baldwin et al note, initial return to work had been the sole objective in their survey ofOntario workers with permanent impairment, they would have had to assume that 85% ofthe workers recovered and returned to work. In fact, they found that 61% of the workerswho initially returned to work incurred periods of work absence related to the originalinjury (Baldwin et al, 1996). Crook et al (1998, in press) found, in a prognostic follow-up study of injured workers, that if the worker had not returned to work (RTW) by threemonths, there was a 50% probability that he/she would be off work at 15 months, and a22% probability that he/she would remain on work disability and not make any attempt toRTW (Crook et al, 1998, in press). Similarly, in a population-based study of WashingtonState Workers’ Compensation, 17.5% of all initial disability claims were found to involveat least 6 months of lost time. A further 12 % involved one year of lost time, and 7.4%involved at least 2 years of lost time (Cheadle et al, 1994).

Current research in the area of musculoskeletal injury and pain has sought to elucidate,among other things, the natural history and trajectory of recovery, prognostic factors, andoutcome measures. The research has employed a variety of designs, includingepidemiological survey follow-ups, long-term prognostic examinations of specificconditions/problems, and long-term follow-ups of treatment with control groups, in theinvestigation of these issues. This body of research is discussed below.

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The Research on Natural History and Trajectory of Recovery

Investigation into the process of recovery and/or development of disability has yieldedconsiderable information on the natural history of post-traumatic musculoskeletal pain.At this juncture, there appears to be four critical findings. First, the research suggests thatthere is a higher level of persistent pain and functional disability than previously assumed(Wahlgren et al, 1997; Von Korff and Saunders, 1996; Von Korff et al, 1993). VonKorff, in a study of primary back pain patients, reported that 24% of recent onset patientsand 36% of non-recent onset patients experience a fair to poor outcome in the long-term(i.e., at one year follow-up). Approximately 33% of primary care patients with back painexperienced back pain of at least moderate intensity and 15% reported severe intensityback pain. Twenty to twenty-five (20 to 25) percent of patients, the research suggests,will continue to report substantial activity limitation (Von Korff and Saunders, 1996).Wahlgren et al (1997) conducted a cohort study of 76 males experiencing a first episodeof back pain. Follow-ups were made at 2, 6 and 12 months. At 6 and 12 months post-pain onset, most (78%, 72% respectively) continued to experience pain. Twenty-six (26)percent at 6 months, and 14 % at 12 months, reported marked disability. Follow-upmeasurement revealed greater change in the cohort in the 2 to 6 month interval than inlater assessments. By 6 and 12 months, there was relative stability. The authors suggestthat individuals at risk for marked symptoms one year after the initial episode of backpain can be identified early. Unwarranted assumptions based on administrative data onreturn to work, or on health care utilization, do not provide an accurate reflection of thenatural history of back pain. All acute problems do not completely dissipate within 6months. Many individuals return to work or do not seek medical care but may continueto experience moderate to severe back pain (Von Korff, 1994; Linton, 1997).

A number of studies suggest that there is high variability in sub-acute and chronic painconditions (Turk and Rudy, 1988; Von Korff et al, 1992; Klapow et al, 1993; Tunks,1990) and trajectories (Crook et al, 1989; Crook and Moldofsky, 1996). The course ofback pain, for example, has been found to be highly unpredictable and unstable (VonKorff and Saunders, 1996; Linton and Hallden, 1997). It is now clear that there is a widerange of outcomes in workers whose injuries initially appear similar. A majority ofinjured workers will achieve full recovery; however, others will suffer recurrent episodesand a small minority will go on to chronicity and disability.

The research into pain trajectory reveals the impact of treatment upon the clinical courseof post-traumatic pain. Comparing untreated to treated conditions in long-term of one ormore years, untreated conditions were found to show not dissimilar trajectories ofrecovery of pain, disability and return to work, although treated groups had an initialadvantage (Lindstrom et al, 1992; Mitchell and Carmen, 1990). An increase in othermusculoskeletal morbidity with time was noted even in treated individuals, but more inthose untreated (Lindstrom et al, 1992; Harkapaa et al, 1990).

A body of current research suggests that there is a “perseveration” effect in the clinicalcourse of musculoskeletal pain (i.e., some workers will fail to get better but not get worsewhile others will improve) (Philips and Grant, 1991a,b; Philips et al, 1991). Wahlgren et

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al (1997) suggest that problems associated with chronic pain may not reflect aprogressive worsening of symptoms, but rather a failure of symptoms to resolve afteronset (Von Korff and Saunders, 1996). Other research challenges this notion of“perseveration” of injured workers. Change, according to this body of research, is farmore multi-dimensional than the “perseveration” effect would suggest. Crook andMoldofsky (1996), for example, demonstrated that some variables improved equally overtime and other variables tended not to improve very much, or to improve rather unequallyover time. McArthur et al (1987) also found considerable variability in outcomemeasures, not the simple dichotomy of better-worse suggested by the perseverationeffect. McArthur et al (1987) conducted a 5 year follow-up of treatment outcome of acognitive behavioral program for chronic low back pain patients. They reported that 12%of the cases had completely favorable outcomes on 6 behavioral measures; RTW, not inlitigation, low self-rating of pain, pain does not prevent activity, not using painmedications, and not hospitalized for pain. On average 7% of the cases reported acomplete lack of favorable outcome. On certain measures, such as RTW and Use ofMedication, the results indicated a steady improvement over time for participants of thetreatment program. In other areas, such as the Impairment of Activity, the results werenot consistent over time. At the first long-term follow-up, a small but significantproportion of participants reported favorably on all 6 measures. At all subsequent follow-ups, the majority of these successful participants reported no change in status. Inaddition, a number of unsuccessful participants no longer reported any unfavorableoutcomes. A few cases in later follow-ups, however, reported one or more unfavorableoutcomes, and a large percentage of the sample never presented a completely successfulpicture at any observation. Maruta et al (1998) followed a cohort of patients with chronicpain 13 years after treatment in a pain management center. As there was no controlgroup, comparisons were not made and any inferences would be speculative;nevertheless, several observations are of interest. First, there was improvement inemployment status on follow-up (from 12% employed pre-treatment to 25%). Second,there was long-term stability in reports of bodily pain (68% of the respondents), andproblems with work or other daily activities, social functioning and physical functioningwere attributed to this pain.

PROGNOSIS

Risk and Prognosis

Factors associated with a higher rate of back pain have been reported to include heavy,unpleasant, and dangerous work (Major, 1970; Spitzer et al, 1987) higher age and lowerwage (Volinn et al, 1991), and previous pain sicklistings (Goertz, 1990; Pederson, 1981).

The desire to predict injury, disability and handicap has led to a multitude of studies, eachclaiming to have found a significant explanatory variable. A distinction, however, mustbe made between factors related to an increase in the risk of incurring injury or anincident of pain and those related to the clinical course of an injury already sustained.The two have separate foci and, more importantly, different related factors –i.e., thefactors associated with an increased risk for injury are not necessarily the same as those

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associated with a worse prognosis (Crook, 1994). Some factors, e.g. heavywork/labor/construction, may be both a risk factor for back injury and a prognostic factorfor continued work loss. A discussion of the risk factors of injury is outside the scope ofthis paper. For information regarding risk factors for an incident of pain or injury, thereader is referred to one of the following published reviews: Battie and Bigos, 1991;Borenstein, 1990; Hulshof et al, 1987; Taylor, 1989; Pope, 1989; Yu et al, 1984;Frymoyer and Cats-Baril, 1991; Frymoyer and Pope, 1978; Frymoyer et al, 1983; Troup,1984; Heliovaara, 1989.

Prognostic Factors

The probability of return to work decreases with months off the job. At 2 months it isabout 70%, at 6 months 50%, at 12 months 30%, and at 2 years l0% (Waddell, 1992).As noted supra, several studies have independently confirmed that it is the small numberof chronic claimants who accrue most of the back injury costs (Spitzer et al, 1987;Spengler et al, 1986; Snook, 1988; Webster and Snook, 1990; Volinn, 1991). Little isknown about those workers who are at high risk for developing a chronic problem andcontinued work disability. A number of studies have identified many potential factorsassociated with a worse prognosis in musculoskeletal pain. Unfortunately, few of thestudies met accepted methodological standards for studies of prognosis. The mostserious methodological shortcomings were: (a) a failure to distinguish between etiologicand prognostic factors; (b) a failure to control for the time at which subjects wereenrolled, and; (c) a failure to perform multivariate analysis (Crook, 1994; Crook andMoldofsky, 1998). Given the methodological quality of the studies, the evidencesuggests that, out of the hundreds identified, only the following factors may affectrecovery; socio-demographic factors, work factors, compensation factors, physicalimpairments, psychological impairments, functional disabilities, and social support (SeeAppendix for “Factors Summary”).

Socio-demographic Factors

Scoio-demographic factors have been examined by several researchers. Increasing agehas been positively associated with increased work disability (Rossignol et al, 1988;Goertz, 1990; Volinn et al, 1991; Cheadle et al, 1994; Butler et al, 1995). Lower levelsof education were more likely to result in lower rates of returning to work (Deyo andDiehl, 1988; Butler et al, 1995). Similarly, lower socioeconomic status and lower wagehave been reported as important factors in work disability (Deyo and Tsui-Wu, 1987;Volinn et al, 1991).

The influence of gender on work disability has also been examined. In worker surveys,women had fewer injuries than men, but a significantly increased risk of having a highcost injury claim (Spengler et al, 1986). However, the pattern was not noted byRossignol et al, 1988, Coste et al, 1994 nor Cheadle et al, 1994. Females had one-thirdthe rate of return to work of males, although they were more likely to remain at workonce they returned (Crook and Moldofsky, 1994). This finding was in contrast to that ofButler et al (1995), whose results showed that gender does not affect the probability of

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returning to work, but among those who return, women are much more likely than men toexperience multiple spells of work absence and unsuccessful returns-to-work.

Work Factors

Length of time out of work (Gallagher et al, 1989), strenuous work, the overall workingenvironment and conditions, the interaction of job demands, and the physical limitationexperienced in performing work, have been associated with an increase in the duration ofwork disability (Yelin et al, 1986). Job dissatisfaction and adversarial relationships on thejob have also been implicated (Bigos et al, 1991), although work dissatisfaction may alsobe a function of the inability to perform the job (Dehlin and Berg, 1977) or the symptomsexperienced during activity (Feuerstein et al, 1985; Sandstrom and Esbjornsson, 1986).Conversely, job availability (Polatin et al, 1989), ease of changing occupations (Gallageret al, 1989; Hewson et al, 1987), use of aids, and modified job requirements to promote afit between worker’s capacity and the job requirements are important factors indecreasing work disability (Yelin et al, 1986; Crook et al, 1998, in press). Theavailability of a modified job was found to be positively associated with return to workrates. The rate was doubled in instances where a modified job was available to injuredworkers upon their return to the workplace. Some of the ways employers modified jobswere through a change in the physical or cognitive demands of the job, shorter hours,more/longer rest periods, modification of machinery, and/or a decrease in expectedoutput (Crook et al, 1998, in press). The number of times work re-entry is tried increasesthe likelihood of success in returning to work (Crook, 1994). Larger firms had shorterdurations of disability (Cheadle et al, 1994).

Compensation Factors

Some authors have regarded compensation as being a prognostic factor in theperpetuation of pain disability (Fordyce, 1995; Battie and Bigos, 1991), but thisviewpoint has not been universally accepted. Dworkin et a1 (1985) found thatdifferences in pretreatment disability were a key variable. Those who were not workinghad poorer outcomes than those who still worked, and when employment andcompensation were used to predict outcome in a multiple regression analysis, onlyemployment was significant. Flor et a1 (1992) found, in a meta-analysis, that virtually nosignificant correlations were found between effect sizes of treatment, compensation andlitigation, pain duration, treatment duration, or age. Some clinicians have recommendedlegal settlement before beginning rehabilitation (Sternbach, 1987). This serves only todelay treatment and to decrease likelihood of favorable outcome.

Physical Impairments

The prognostic importance of pain characteristics has been examined by severalresearchers. The site of symptoms (Rossignol et al, 1988; Cheadle et al, 1994; Butler etal, 1995), the number of painful sites (Crook et al, 1998, in press; Von Korff et al, 1988),pain grades (a measure based on pain intensity and number of disability days) (VonKorff, 1991), and pain behavior (Crook et al, 1998, in press) were found to be

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prognostically important. Previous pain sick-listings have also been implicated (Goertz,1990).

Several measures of health, for example general health (Biering-Sorenson, 1986), andoverall health status (Von Korff, 1991), affected the probability of work loss. Fatiguewas also identified as an important factor in relation to work disability (Linton et al,1989).

Psychological Impairments

Comorbidity of persistent pain with psychological factors, particularly depression andanxiety or dysthymic conditions, is an important clinical and prognostic factor (Dworkinet al, 1986; Valfors, 1985; Crook et al, 1988; Tunks, 1986). There are several studiesthat demonstrate almost a three-fold risk of development of depression in theapproximately 2 years from onset of chronic pain (Atkinson et al, 1988; Brown, 1990;Magni et al, 1994; Breslau et al, 1994). The presence of depression is an important factorin increasing pain intensity, impairment, and behavior (Haythornwaite et al, 1991). Forthis reason, identification and treatment of depression is of high priority in persistent painsufferers. Crook et a1 (1986) demonstrated that psychosocial factors had an importantinfluence in the selection factors that brought persistent pain sufferers to specialty clinics.These factors also importantly influenced prognosis on follow-up (Crook et al, 1986) andreturn to work (Crook et al, 1998, in press).

Functional Disability

The prognostic importance of functional disability in relationship to work disabilityappears well-established from early studies (Berkowitz, 1976; Nagi, 1976). Limitationsin specific physical functions, namely walking, bending, and climbing, contributed towork disability (Yelin et al, 1986). Activities of daily living (Sandstrom and Esbjornson,1986) or discomfort in activities (Turner et al, 1983) were also identified asprognostically important.

Social Support

Social support has been suggested as a buffer or modifier of the effects of injury. Thereis descriptive evidence that chronic pain sufferers experience continuing stressors,particularly in the areas of diminished social functioning, role changes, financial, maritaland sexual strain. These factors have not been examined in methodologically soundstudies so their influence on chronicity or work disability remains suggestive only.

Changes in Prognostic Status as a Function of Time

Time dependent covariates describe changes in workers’ prognostic status as a functionof time. The importance of time-dependent models lies, partly, in their ability to identifychanges that occur over time. One cohort study of workers with musculoskeletal injurieswho had not returned to work by 3 months (Crook et al,1998, in press) has dealt with theeffects of variables that may change over the follow-up period. The variables examined

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were: pain, physical and psychological impairments, functional and social disability, andthe resulting handicaps. These variables were entered into time-dependent models.Functional disability and handicap for physical independence were negatively associatedwith return to work rates.

How Prognostic Indicators can be Interpreted on an Individual Clinical Basis

While the above indicators show significant relationships to outcome, and are useful andimportant flags, it is seductive and erroneous to use them in a prescriptive fashion inindividual casework. An adjudicator who finds report of multiple predictive factors attwo months should not use this to disallow further treatment/claims, since thesepredictions hold for groups, and not necessarily for individuals. However, red flags canbe useful in early identification of those who require special attention, more vigorousmultimodal assessment/treatment, or interpretation of treatment failures.

Crook and Moldofsky (1996) developed cluster groupings of workers who had notreturned to work by 3 months post-injury based on prognositically important clinicalvariables; pain sites, functional limitations and pain behaviors. Their purpose was todivide the original cohort into subgroups of injured workers who were similar in theirprognostic expectations in relation to future work disability. Those considered high levelimpaired (25%) had the highest number of painful sites, the highest number of functionallimitations and pain behavior. When followed over time, the highest level impairedinjured workers tended to demonstrat the greatest emotional distress and interference inoccupational, social, familial and recreational roles, and these difficulties increased overtime. Pain, sleep disturbance, fatigue, and overall impairment increased over time in thehigh risk group. The ability of these three variables to predict RTW in injured workerswho were sick-listed for 3 months was deemed valid.

SYSTEMATIC REVIEW OF REVIEWS:

In order to search for relevant publications, searches were performed in Medline/Pubmedand in the Cochrane Library. There was no specified time limit. Searches wereperformed with respect to clinical disorder, publication type, intervention type, and“related articles”. The categories for clinical disorder were; pain and chronic disease,back pain, neck pain, cumulative trauma disorders. The categories for publication typewere; meta-analysis, systematic review, RCT, follow-up studies, treatment outcomestudies, and practice guidelines. The categories for intervention type were; cognitivetherapy, combined modality therapy, multimodal, manipulation, chiropractic, patienteducation, psychotherapy, behavior therapy, cognitive therapy. The “related articles”option was chosen in Medline/Pubmed. Language choice was English.

While the main strategy was to retrieve quality systematic reviews and meta-analyses toperform a review of reviews, the literature on injection therapies for “myofascial pains”and soft tissue pain, and on opioids for nonmalignant pain, has only a few RCTs. Hence,these RCTs were used for the section on “injection therapies”, and on “opioids”.

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The retrieved articles were hand-searched for articles that may have been missed by thecomputer searches. Other experts were consulted for other articles that might have beenmissed.

Inclusion criteria were systematic reviews or meta-analytic reviews of non-surgicaltreatment of non-malignant chronic musculoskeletal pain. Exclusion criteria werenarrative reviews, reviews that did not include either natural or clinical course, ortreatment. Some retrieved citations were rejected on the basis of published abstracts, anda few were rejected after the authors scanned the retrieved articles for inclusion criteria.

Meta-analytic and reviews were independently rated by the authors using the criteria ofOxman and Guyatt (1991). RCTs were rated by one author using the criteria of Jadad etal. (1996). Author blinding was not used. Tables were constructed to summarize thesignificant findings from this review of reviews, and this was employed for the study andalgorithm. There was complete agreement between independent raters on the quality ofstudies, and on those which should be included or excluded. Table 1 summarizes theincluded studies, and Table 2 summarizes the three excluded studies.

Physical Therapies for Chronic Nonmalignant Pain

Outcome assessment in the selected meta-analyses did not reflect a uniform strategy.This is often due to a wide diversity in experimental design and the plethora of outcomemeasures in this field, but also has to do with other factors such as poorly designedstudies.

Four of the meta-analyses used the judgment of whether the physical therapy weremore effective than the comparison treatment,one used Odds-Ratios,one used pooled p-values,one used the calculated mean difference and confidence intervals between thephysical therapy and comparison condition,and one used Effect sizes.

Manipulation and Manual Therapy

Beckerman et al. (1993) and Koes et al. (1991) found that some studies on chronic backor neck pain showed a favorable outcome with respect to comparison condition, onmeasures of function, and sometimes on pain measures. Better studies tended to notdemonstrate a significant difference between the manual/manipulative therapy andcomparison treatment. Hurwitz et al. (1996) found that the pooled Effect Size for themanipulation condition outcomes approached significance on measures of pain relief (ES= 0.42). The evidence leans to a conclusion that manual therapies/manipulation areprobably efficacious, for pain and/or function, in chronic neck/back pain, but the efficacyhas not been demonstrated to be pronounced or universal.

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Ultrasound

Beckerman et al. (1993) concluded that the evidence for ultrasound vs. comparisontreatment for chronic MSK pain was inconclusive. Ultrasound cannot be recommendedfor chronic MSK (back/neck) pain.

Soft Laser

(Because the Beckerman et al. 1993 meta-analysis recapitulates and enlarges on theBeckerman et al. 1992 meta-analysis, only the 1993 study is discussed here.)

Beckerman et al. (1993) noted that soft laser appeared in several studies to be moreeffective than placebo, but efficacy was not apparently linked to dose. Gam et al. (1993)concluded that the best studies showed no evidence for effect on MSK pain, though somebenefit was reported in poorer quality studies. Gross et al. (1997a) concluded that softlaser was not effective. Soft laser cannot be recommended for chronic MSK (back/neck)pain.

Therapeutic Exercise

Spitzer et al. (1987) concluded that active exercise was helpful for LBP of greater than 7weeks duration. Beckerman et al. (1993) however found 6 years later that the evidencewas inconclusive, whereas Gross et al. (1997a) concluded that there was some positiveadvantage for active exercise, in comparison to passive exercise/treatment. The balanceof the evidence points to active exercise being effective for persistent LBP, in contrast topassive physical therapies.

Electromagnetic Therapy

Gross et al. (1997a) concluded that the studies they reviewed appeared to demonstratesome benefit at about 3-4 weeks, but not at 6-12 weeks. Beckerman et al. (1993) notedthat of 18 trials retrieved, 9 were of better quality. Of these 9, one demonstrated theefficacy of electromagnetic therapy vs. placebo. On the basis of this evidence, onecannot conclude that electromagnetic therapy is effective.

Transcutaneous Electrical Nerve Stimulation (TENS or TNS or ALTENS)

(Note that ALTENS or “acupuncture-like TNS” actually refers to low-frequency TNS, asopposed to the higher frequencies that are often used in TNS. One should not confuseALTENS with acupuncture . The above are all forms of electrical stimulation applied tothe skin.)

Spitzer et al. (1987) concluded that for LBP of greater than 7 weeks duration, TNS waseffective in pain relief. Gadsby and Flowerdew (1996) used Odds Ratios to comparestudies of TNS and ALTENS and comparison treatments. On pain measures, they foundan Odds Ratio of 1.6 comparing TNS with placebo. They found Odds Ratio of 2.11

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comparing TNS/ALTENS vs. placebo, but with no improvement of functional status bySIP. For ALTENS vs. placebo, they found an Odds Ratio of 7.22 for pain relief, and 6.61for improved range of motion. Gross et al. (1997a) found no significant differences inresults of studies comparing TNS with conservative physical therapy. In persistent MSKpain, TNS offers at least short-term relief, but not better than the relief from conservativephysical therapy. Low-frequency stimulation offers a greater efficacy with regard to painand improved range of motion at least in the short-term. (Author’s note: low-frequencystimulation is often more intense and some patients do not tolerate it well.) However,Malone and Strube (1988) , (on 2 studies) did not find TNS to have a higher percentageof patients improved than with control condition, and Effect Size for TNS was 0.46 .

TNS may be recommended in certain cases, but is probably inadequate by itself, andneeds to be complemented by other avenues to deal with function.

Traction

In the meta-analysis by Gross et al. (1997a), comparing studies of traction vs.conservative physical therapy for neck pain, no significant differences were found tosupport traction as treatment for MSK pain of the neck. Traction cannot berecommended for chronic spinal pain.

Bed Rest

In their systematic review in 1987, Spitzer et al. reported that bed rest of not more thantwo days could be recommended for acute back pain without radiation to a leg (sciatica),but bed rest could not be recommended for more persistent back pain conditions.Prolonged bed rest should not be recommended for back pain.

(There is more recent evidence, noted in the narrative review in a later section, that bedrest for acute back pain is less effective than advice to continue activity within tolerance,in hastening recovery.)

Systemic Medication

NSAIDs, analgesics, and muscle relaxants, were found by Spitzer et al. (1987) to beefficacious for LBP of less than 7 days, and not for LBP of longer duration.

Epidural Cortisone (for sciatica)Watts and Silagy (1995) reviewed the evidence for efficacy of epidural cortisoneinjection for LBP with sciatica. In this systematic review, they calculated Odds Ratios tocombine results across studies. The Odds Ratio for short-term relief by epiduralcortisone was 2.67, for near complete relief was 2.79, and for long term relief the OddsRatio was 1.87. Both caudal and lumbar injection route were found to be effective.

For sciatica associated with LBP, epidural cortisone injection can be recommended.

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Antidepressant therapy for Pain Relief

Onghena and Van Houdenhove (1992) were able to calculate Effect Sizes in order tocombine the results of many antidepressant studies. They concluded that TCA (tricyclicantidepressants) were more effective than comparison conditions (ES = 0.69). The EffectSize for heterocyclic antidepressants vs. comparison conditions was 0.36.Antidepressants were more effective for pains in the head region (ES = 0.93) than inother body regions (ES = 0.44). The analgesic effect was unrelated to organic vs.psychogenic diagnosis, or to the presence of comorbid depression or to an apparentantidepressant effect of treatment, and unrelated to the presence or absence of sedation.It was noted that drugs with a “less selective” biogenic amine reuptake inhibitory effectappeared to be associated with a higher Effect Size (ES = 0.73), than drugs with a moreselective effect on biogenic amines (ES 0.32 to 0.40).

Antidepressants can demonstrate analgesic effects, and not just antidepressant effects, inchronic pain conditions.

Psychological Treatments for Chronic Pain

Unimodal Psychological Treatments

Malone and Strube (1988) calculated Effect Sizes in order to examine the efficacy ofvarious psychological treatments in comparison to no treatment. Effect size for“autogenic training” was 2.74, for biofeedback was 0.95, for relaxation was 0.67, and for“placebo” was 2.23. (That is, placebo was more effective than no treatment, and wascomparable to some psychological treatments.) However, they also found that operanttherapy had effect size of 0.55, which is scarcely different from the control condition.

Patient Education and Back/Neck School

For LBP of greater than 7 days duration, Spitzer et al. (1987) found that “Back School”,or “functional training” or “ergonomic intervention” could be recommended. Cohen etal. (1994) found that reports on patient education for back/neck pain showed inconsistentoutcomes. In acute LBP, education interventions reduced pain duration and initial sick-leave in one of two relevant studies. For chronic LBP, relevant studies were inconsistentwith regard to pain and function as outcomes of the education intervention. In theirreview, Cohen et al. concluded that education was more effective than passive treatmentor no treatment, but exercise and active treatment was as effective as or better thanpatient education. DiFabio (1995) found that patient education was not as effective asmultimodal therapy with regard to pain and functional outcomes. Gross et al. (1997b)found that education with or without associated medical or physical therapy did notsignificantly alter pain outcomes.

Although patient education plays a useful role in therapist-patient interaction, andeducation is a standard part of multimodal therapy, by itself it is an inadequate treatmentfor chronic neck and back pain.

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Multimodal Pain Management Programs

Malone and Strube (1988) found an Effect Size of 1.33 in comparing the efficacy ofmultimodal programs to no treatment. Flor et al. (1992) found that multimodal therapiesin comparison to controls had effect sizes of 0.62 (for shorter duration pains) and 0.81(for longer duration pains). With regard to return to work as an outcome, they found amean Effect Size of 0.67, (reflecting a combined return to work in 68% of multimodal-treated patients and in only 36% of control patients.) Multimodal techniques were moreeffective than single-modality treatments. The greatest efficacy difference was seen incomparing multimodal with placebo/no treatment, and smaller differences were seen incomparing multimodal with physical therapy. DiFabio (1995) found that multimodaltherapy combined with “patient education” was more effective than patient educationalone with respect to improving pain and function. Studies of inpatient multimodalprograms demonstrated greater effect sizes than comprehensive outpatient multimodalprograms.

These results strongly indicate the efficacy of multimodal pain management programs.There is no evidence for the superiority of any particular psychological therapy “school”in the operation of multimodal programs. There is adequate demonstration that “backschool” alone is not adequate as treatment unless it is combined with other activemodalities which usually include goal-setting, active exercise by quotas, some form oftension control training or coping skills training, vocational counselling, and usuallysocial systems intervention. The intensity of the treatment itself is probably an effectiveingredient for this therapy, which is indicated for patients who do not show the expectedpattern of recovery from persistent pain.

SYSTEMATIC REVIEW OF INJECTION THERAPIES FOR CHRONIC PAIN

Additional RCTs were retrieved using the above search strategies and including the termsinjection, anesthetic-local, chronic pain, and related citations. Bibliographies werehandsearched for additional articles. Data bases were the same as for the above review ofreviews. All 12 retrieved articles were graded for quality according to Jadad et al.,(1996). No article was discarded on quality alone, since the number of RCT’s was notlarge. All are summarized in Table 3. Of the twelve RCTs located, three were graded at 5on a scale of 0-5, where 5 is the highest score. One was graded at 4, seven were graded at 3,and one at 2. (See table 3)

Injections into soft tissue for chronic back and neck pain and myofascial pain

Nine dealt with injections into soft tissue. Of these, two were graded at 5, one at 4, five atgrade 3, and one at 2. Ongley et al. (1987) reported a study of a rather complex treatmentconsisting of injection of a proliferant (sclerosing) agent plus cortisone and lignocaine, plusmanipulation: this was compared to a control condition of saline, lignocaine, and minormanipulation. The experimental treatment was more effective than the control. This was

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one of the better studies, but it does not allow one to decipher the relative efficacy of thecomponents of the treatment.

The three studies that compared soft tissue saline injection to comparison treatment came tocontradictory results. The best of these three studies favored saline to lignocaine injection ina period up to two weeks.

The study by Sonne et al. (1985) favored lignocaine plus cortisone over cortisone alone onself-report and pain up to 2 weeks. The three studies of lignocaine vs. comparison injectioncame to contradictory results, but the best of these studies (Frost et al., 1980) favored salineover lignocaine up to 2 weeks. One of the best studies (Garvey et al., 1989) failed to showan advantage of invasive treatment (either injection or acupuncture) over non-invasivetreatment (vapocoolant and acupressure).

These results do not support the efficacy of injection therapies over control treatment forchronic back, neck, and myofascial pain.

Injections into spinal facet joints for low back pain

Of the three studies in this group, one was graded 5 and two were graded 3. The best studyby Carette et al. (1991) found that at six months, but not at one and three months, patientswho had the cortisone injection into facet joints fared better than those with saline injectionto facet joints, on pain and function measures. However, Marks et al. (1992) found thatthose with facet blocks were significantly better only at one month than those who hadblocks around but not in facets, but significant advantages were not found at other times upto three months followup. Lilius et al. (1989) found that there were no advantages of facetover non-facet injections, or of cortisone over non-cortisone injections.

Facet injection for chronic back pain is not supported by these studies.

Injection of cortisone vs. comparison for low back pain

In this group, two studies were graded 5, and three were graded 3. The two best studies(Garvey et al., 1989; Carette et al., 1991) came to contradictory results. Of the five studiesin the group, three came to the conclusion that cortisone injections (with or withoutanesthetic) was significantly better than comparison treatment on measures of pain and self-report.

Injection of non-cortisone agents vs. comparison for back/neck/muscle pain

Of the seven studies in this group, two were graded at 5, one at 4, three at 3, and one at 2.Inconsistent results were found for saline vs. lignocaine (two studies), and for saline vs.sterile water (two studies). Garvey et al. (1989) did not demonstrate greater efficacy forinvasive treatments, while Ongley et al. (1987) demonstrated efficacy for a complexintervention that involved both invasive and noninvasive components.

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Injection therapies for pain in the upper back/neck or the lower back

Three studies involved upper back/neck pain, while eight involved lower back pain. Thebest studies tended to involve lower back pain, but there were no studies comparingoutcomes in pain relief in upper vs. lower back. There did not appear to be any trend foreither upper or lower back studies to reflect a greater success rate of experimental vs. controlcondition.

Injection therapies for pain greater than or less than three months

Eight studies concerned patients with pain of three months or more, one concerned "acute"myofascial pain, and from three studies it was not possible to clearly determine paindurations of subjects. There did not appear to be trend for shorter or longer duration pain toreflect a greater success rate of experimental vs. control condition.

Although injection therapy of anesthetic or cortisone into chronic back or neck soft tissue orfacet joints is a widespread clinical practice, the evidence for efficacy for injection ofanesthetic, saline, sterile water, or cortisone into painful soft tissues or facet joints is at bestinconsistent and contradictory.

OPIATE FOR CHRONIC NON-MALIGNANT PAIN

Although there is a growing literature which increasingly favors the practice of prescribingopiates for some patients with non-malingant chronic pain, to date most of the literature hasdepended on uncontrolled studies and extrapolations from palliative care practice (Portenoy,1994). Consensus guidelines have also been drawn up in several jurisdictions for opiate usein nonmalignant pain, including Alberta College of Physicians and Surgeons (1993), theBritish Columbia College of Physicians and Surgeons (adopting the Alberta Guidelines,1995), the joint guidelines of the American Academy of Pain Medicine and the AmericanPain Society (1997), the Medical Board of California (1994), and the American Society ofAnesthesiologists (1997).

A search of the literature only retrieves two RCTs to date that specifically deal with thisissue. Both are good studies. Arkinstall et al. (1995) report an RCT double blind study of30 patients with diagnoses mostly of a variety of MSK disorders. Although the illnessduration is not given, the mean opiate duration use was 72.6 +/- 65.8 mos. Moderate dosesof sustained release codeine were compared to placebo, over a week, with a further 19weeks of unblinded use for followup. The outcomes significantly favored the codeine onpain, PDI, self-report, and use of rescue doses, and efficacy was not apparently lost duringthe further unblinded use.

Moulin et al. (1996) conducted an RCT double-blind study on 46 patients with a variety ofmusculoskeletal disorders, of duration 4.1 years (0.75-21 yr). Moderate doses of sustainedrelease morphine were compared to active placebo (benztropine) over a study duration of 9

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weeks (before crossover). The morphine group did significantly better on pain, but othermeasures including PDI, drug liking, and a mood scale failed to show significant difference.A sequence effect was noted at the end of the first arm of the trial, influencing the results ofthe second arm of the trial.

The conclusion from the above is that there is some evidence that a mixed diagnostic groupof chronic MSK patients will experience at least pain relief, if not self-report of functionalimprovement, in nine to nineteen weeks of followup, using sustained release opioids inmoderate doses. Whether a more liberal view towards the use of opioids in nonmalignantpain leads to longer-term problems of analgesic failure, complication, or misuse, in thispopulation is still to be ascertained by further studies.

MEASUREMENT ISSUES IN OUTCOMES

Flor et al. (1992) found greater differences in outcomes by using less subjectivemeasures, and more objective and functional measures, in studies of multimodaltreatment. Malone and Strube (1988) found that reported symptoms, mood, and EMGrecordings consistently showed improvement, and the least variation, as outcomes forpsychological interventions.

Measures and Clinical Indicators

Numerous measures exist and no one measure can be generally recommended for alladministrative or clinical purposes. There are no gold standard measures forpsychological comorbidity, physical function, or pain-distress. However, in every casewhere differences are demonstrated, the differences can be accounted for by these threevariables (for example, see Harkapaa et al., 1990): i.e., it is good counsel to advise avalidated measure in each of these three categories.

Time is also a factor that must be considered in interpreting studies. Numerous studiesdemonstrate that between two and six months, those who have not yet recovered arehighly likely to have persistent significant problems at one year or more (Von Korff,1988; Wahlgren, 1997; Barnsley et al, 1994).

Measures serve different purposes and must be chosen accordingly. Scientific studiesdepend on widely accepted objective standardized measures designed for the populationunder study. These same measures may be useful as flags in individual cases, though noone objective measure recommends itself for all individual cases. However, self-reportmeasures, and those with more of a subjective quality, may be more helpful in certainclinical situations, in individual case management/decision making by clinicians (i.e.,pain drawing, pain scales, disability rating, depression/psychological distress scales, etc).

The choice of an outcome variable is almost inevitably a compromise based on theinterplay among several factors:

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The Precision of the Measures

Measures that are subject to a large degree of random variation or individualinterpretation are less useful than measures that are more precise and reproducible. So-called “objective measures”, such as radiology, have high error rates. In addition, resultsof commonly used diagnostic measures have often been found to bear little relationshipto symptoms, function, well-being and/or vocational/employment status. Measuresshould be valid and reliable (Flor et al, 1992; Gross, 1997; Beckerman et al, 1993.

Importance

The outcome variable(s) should possess relevance to the burden of illness on the injuredworker, and/or compensation system(s), and/or the workplace, and/ or society in general(Feine and Lund, 1997).

Sensitivity/Responsivenes

For a variable to be useful, there must be some reasonable chance that it is related to, orlikely to change with, the independent variable under study (Beckerman et al, 1993).

Appropriate

The outcome variable(s) must be appropriate to the research goals and to the treatmentbeing tested.

Decision Rules If Several Outcome Measures Are Used

A multi-dimensional model of outcomes is needed (Malone and Strube, 1988). Priorityof the outcomes must be specified prior to the research where several outcome measuresare used, since by chance some outcomes may change while others do not change.

Choosing Optimal Points for Measurement of Outcomes

Prior to undertaking research, investigators must consider the relative importance of the outcome variablesin relation to the “natural” clinical course of the illness/injury (Cohen et al, 1994). To accomplish this, onemust have access to relevant epidemiological research regarding similar clinical groups, in order toestablish the expected course of similar patients with or without the intervention under study. Considerthese examples. The natural history of musculoskeletal injury is variable, with a wide rangeof outcomes in patients whose injuries initially appear similar, often due to associatedclinical factors that may or may not be clearly identified (Crook and Moldofsky, 1996).Overestimation of favorable prognosis of persistent musculoskeletal pain may be due, inpart, to short term clinical results combined with considerable natural fluctuation inmusculoskeletal pain giving an appearance of rapid recovery (von Korff and Saunders,1996; Wahlgren et al, 1997). Inadequate understanding of the highly variable course ofback pain can lead to false conclusions about the need for and the benefits of therapeuticinterventions (Von Korff, 1994; Linton, 1997)

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Blinded Outcome Measures should be Used

Blinded outcome measures reduce expectation bias; that is, blinded measures prevent thesituation where the assessor finds the results he/she expects, or outcomes favoring thetreatment s/he prefers.

Measures chosen should have been validated in samples of people who are similar tothose on whom the measure is to be presently used.

Different instruments may alter the description, intervention and priorization ofmusculoskeletal injuries (Beaton et al, 1996).

Outcome Measures must be Comparable to Draw General Conclusions across Studies

Collaboration among researchers often depends on ability to use the same standardizedoutcome instruments, across studies that target different interventions, industries, oroccupations. These outcome measures can generally categorized into patient variables,work disability and benefit status variables, and health care utilization variables.

Outcome Variables:

1. Patient Variables - Patient variables include: pain (duration; recurrences; severity;persistence) (Schierhout and Myers, 1996); adjustment & quality of life (Pransky andHimmelstein, 1996); functional ability and increased activities of daily living;success/improvement (good vs. poor responders); chronicity (defined in a variety ofways), and; psychological disturbance/depression.

2. Work Disability – Work disability is, generally, assessed by: time away from work,length of sickness absence, work days lost, RTW, recurrent absenteeism, and/orbenefit status (Burdorf et al, 1997; Pransky and Himmelstein, 1996; Baldwin et al,1996).

3. Health Care Utilization – Health care utilization is often gauged by referrals andvisits to health care professionals, and/or medication use.

MISUSE OF EVIDENCE

It may be tempting for someone looking for a quick answer to a difficult problem to takean uncritical view of good quality evidence. The evidence is good, but the meaning canbe distorted. A few examples are pertinent.

• Unimodal therapies are less efficacious than multimodal for chronic pain (Bigos etal., 1994; Flor et al., 1992; Crook and Tunks, 1996). One cannot assume from thisthat all chronic pain patients should be treated in multimodal programs. The

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economics and logistics of this would be prohibitive. But this serves as a yardstickfor relative efficacy that can guide policies regarding the need for multimodal clinicsas an option when triaging patients to the most appropriate treatments.

• Active therapy superior to passive (Bigos et al., 1994), but this does not mean thatpassive therapy is not helpful, or that it is harmful, if it is combined with multimodal(Gross et al, 1996).

• There is no evidence that any one type (or “school”) psychological treatment issuperior as a component of multimodal therapy (Altmaier et al., 1992; Turner et al.,1990). One cannot extrapolate from this that “the cheaper the better”, and set a policythat restricts multimodal programs to use only the least intensive or most generic oftherapies, since type of therapy still needs to be matched to the quality of the clinicalproblem and capacity of the patient.

• Apart from secondary prevention for those who have already had a pain episode, noliterature shows any method effective for prevention (Daltroy et al., 1997). Backschools/education are not efficacious unless they are a component in multimodaltreatment (DiFabio, 1995). But it does not follow that patient education should beabolished, since it is still an essential ingredient in factors such as patient complaince,the doctor-patient relationship, and the patient’s rights to be informed.

• Patients with high pain reports, high functional impairment, widespread pain, andpsychological comorbidity, have a poor prognosis (Crook and Tunks, 1996). But anadjudicator or adjustor cannot correctly extrapolate from this statistical observation tothe case of a single individual and deny appropriate treatment on the grounds that“groups with these characteristics tend to do poorer”—individuals within a group donot necessarily have the identical outcome to the group as a whole.

Most clinicians are aware that there are now widely accepted guidelines, based on goodscientific studies, that work-injured patients should be treated with active therapies suchas exercise, and expectations that they should make an early attempt to return to work.These guidelines are presented in many publications, including Bigos et al (1994). It isimportant not to misconstrue the guidelines or the evidence on which they are based. Forexample, see below.

• For acute low back pain, Malmivaara et al (1995) assigned patients randomly either totwo days of bed rest, or to prescribed exercise, or to being advised to continue theirroutines as much as permitted by their back pains. At one and two weeks, the normalactivity group had significantly faster recovery than the bed rest or exercise groups,but at twelve weeks there were no differences between the groups. This means thatthe normal activity approach is significantly better in the short-term, and isrecommended during the first month after injury, but one cannot conclude from thisthat “expecting normal activity and return to work” has the identical effect on longer-term outcomes.

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• Lindstrom et al (1992) studied workers with back pain of about 2 months duration.The patients were randomized to 2 groups; one which had treatment by their familydoctors only, and the other groups which had functional capacity measurement, awork-place visit, back care education, and a program of increasing active exercisewith expectation that they should return to work as soon as possible. The activerehabilitation group did better on several measures. Forty-two (42) % of the activetreatment group had no back pain recurrences in the second year follow-up, while21% of the control group had no recurrences in the second year follow-up. Thisshows that in the first two months of back pain occurrence, an emphasis on improvedfunction increases a positive outcome, which can be measured even in the secondyear, but it cannot be assumed that the active approach guarantees a positive outcome;indeed, about 60% of the positive outcome group had had recurrences. An agencyshould not make the assumption that if a patient is sent for appropriate treatment, thatthey must necessarily recover or be deemed unmotivated.

• Mitchell et al (1990) compared outcomes of injured workers (back pain of a fewmonths duration) referred to active treatment (exercise with expectation of return towork), and workers treated only by their own physicians. By the end of the studyperiod, about 85% of workers treated by the active treatment clinics had returned totheir jobs, while about 75% of those treated by their own physicians had returned. Byabout a year, the proportion of workers returned to work was gradually becomingmore similar in the two treatment groups. One cannot assume that because the activetreatment group returned their patients to work earlier, they must have had a betterresult, since forcing returning to work without followup does not ensure that patientsare fit for work and will continue at work.

• Mayer et al. (1985) studied workers who had had chronic back pain an average of 2years. Some were treated with a program of education, active and increasingexercise, and expectation of return to work, while the others were not eligible fortreatment or dropped out of treatment. At one year, 85% of the active treatmentgroup had returned to work compared to 45% of the untreated group, and the activetreatment group had half the rate of health care utilization, and were significantlymore fit, compared to the other groups. This shows the superiority of an activemultimodal program of exercise and education for chronic back pain, but it alsodemonstrates that a positive response to such treatment is more probable, rather thanguaranteed.

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Key Issues• Rigid application of simplistic models of recovery do injustice to proper intervention

and evaluation.

• Important indicators include time, dysfunction, pain-distress, and comorbidity - allshould be considered all along the way.

• True prevention is still undemonstrated.

• Problems that recover slowly probably are multifactorial and require multimodalintervention.

• There is still no gold-standard for the most essential elements of multimodaltreatment; therefore, how to “ensure quality control” if a greater dissemination ofsuch services is contemplated?

New Avenues in Light of WCB Realities

• Need for flexible system of decision-making, using indicators and red flags to aiddisposition but not to use clinical care maps or algorithms rigidly or prescriptively.

• Need to promote a more responsive clinical approach that can adjust to indicators onindividual basis.

• Knowing when to not intervene further, because it is harmful for the patient, andwasteful for the agency. Research is needed into the “red flags” for lack of consent,lack of engagement, and identification of factors that contraindicate chronic paintreatment.

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38

APPENDIX 1

META ANALYSES AND REVIEWS

AUTHORS(Year)

POP. STUDIED

N QUALITYOF

METHODS

N OFSTUDIES

INCLUDED

RESULTS :OUTCOME - EFFECT SIZE

DIRECTION OF EFFECT

Flor H, Fydrich T,Turk D, 1992

ChronicPain

3089 Assessor 1 =Acceptable

Assessor 2 =Acceptable

65 of 300 metinclusioncriteria

Time: Follow-upBetween - group ES (S.D.)

< 6 months = .62 (.47)> 6 months = .81 (.66)

ς30% improvement more than controlς38% improvement more than control

Multimodal compared to singlemodality:

To Medical = .83 (.56)To Placebo = .97 (.13)To Physical Therapy = .41 (.30)

} Multimodal treatments more effective than single treatments

By Outcome Measures:Between - group ES

Psychopysiological = .84 (.26)Behavioral = .65 (.70)Pain = .70 (.66)Interference = 1.10 (.67)Mood = .63 (.33)Other Subjective = .47 (.48)

Return to Work = .67 (.55)Medication = .61 (.63)Health Care Use = .47 (.51)Activity = .63 (.87)Pain Behavior = .61 (.85)Pre-treatment vs. Post-treatment =1.35

Correlations with Effect Size:

Age, pain duration, litigation orcompensation, treatment durationor study quality

} Greater between group differences measured improvement by usingless subjective measures and objective or functional measures

ς treated patients more likely to RTW (68% vs. 36% for control)ς 65% vs. 35% improvementς (missing)ς 65% vs. 35% improvementς 65% vs. 35% improvementς 56% improvement

ς Not significant correlations

REVIEWS OF THERAPIES FOR CHRONIC PAIN

Therapy: Multimodal Pain Treatment

AUTHORS(Year)

POP. STUDIED

N QUALITYOF

METHODS

N OFSTUDIES

INCLUDED

RESULTS :OUTCOME MEASUREPOOLED P-VALUES

DIRECTION OF EFFECT

Gross AR, 1997a Neck Pain 750 Assessor 1 =Acceptable

Assessor 2 =Acceptable

13RandomizedControlledTrials

1 Clinical Trial:Spray and Stretch – NS

1 Clinical Trial:Infared Light Therapy – NS

3 Clincial Trials:Laser Therapy – NS

2 RCTs: (n-60)Electromagnetic field – pooled pvalue = 0.0089Electromagnetic field - pooled pvalue = N.S.

2 RCTs:Acupuncture – data could not beextracted or compared

3 RCTs:Traction vs. conservative therapies

2 Studies:Exercise vs. comparisonconservative treatment (data couldnot be extracted)

1 Study:TENS vs. conservative therapy

ς no benefit (Note - small sample size and/or small number of studies)

ς no benefit (Note - small sample size and/or small number of studies)

ς no benefit (Note – small number of studies)

ς benefit @ 3 – 4 weeks

ς no benefit @ 6-12 weeks

ς both reported positive effect

ς no significant effect in 2 studies, and less effective than comparisontreatment in 3rd study

ς 1 of 2 studies reported significant benefit for active exercise comparedto passive treatment

ς no significant difference

REVIEWS OF THERAPIES FOR CHRONIC PAIN

Therapy: Physical Medicine

AUTHORS(Year)

POP. STUDIED

N QUALITYOF

METHODS

N OFSTUDIES

INCLUDED

RESULTS :OUTCOME – ODDS RATIOSAND (95% CONFIDENCEINTERVALS)

DIRECTION OF EFFECT

Watts RW, SilagyCA, 1995

SciaticaPain

907 Assessor 1 =Acceptable

Assessor 2 =Acceptable

13RandomizedControlledTrials

Treatment vs. Placebo :

OR = 2.61 (95% CI 1.80 – 3.77)OR = 2.79 (1.92 – 4.06)

OR = 1.87 (1.31 – 2.68)

Caudal vs. Lumbar:

Caudal: OR = 3.80 (1.36 – 10.6)Lumbar: OR = 2.43 (i.77 – 3.74)

ς 75% better improvement in the short termς near complete relief of pain

ς relief of pain in long term

} efficacy is independent of injection route

REVIEWS OF THERAPIES FOR CHRONIC PAIN

Therapy: Epidural Corticosteriods

AUTHORS(Year)

POP. STUDIED

N QUALITYOF

METHODS

N OFSTUDIES

INCLUDED

RESULTS :OUTCOME -EFFECT SIZE (S.E. of ES)

DIRECTION OF EFFECT

Onghena P,Van HoudenhoveB, 1992

ChronicNon-MalignantPain

1740 Assessor 1 =Acceptable

Assessor 2 =Acceptable

39 Drug vs. Comparison:

Mean ES= 0.64 (0.59)Range – (1.94 to –0.74)

Tricyclic vs. Heterocyclic Drugs:34 Trials

Tricyclic: Mean ES = 0.69Heterocyclic – Mean ES = 0.36

Region:

Pain in Head region – Mean ES = 0.93

Pain in Other Regions – Mean ES= .44

} a median of 58% reported at least 50% pain reduction

} tricyclic drugs appear more beneficial than heterocyclic

} more benefit for those with pain in head region vs. other regions

NS – pain of organic vs. psychogenic basis NS – presence or absence of depression NS – presence or absence of antidepressant effect

5 HT, NR, or mixed inhibition:

Serotonergic ES 0.32 (0.21)Noradrenorgic ES 0.40 (0.16)Mixed ES 0.73 (0.12)

}All effective but less selective drugs better

Sedative/Nonsedative:

ES ranging from 0.46 – 0.67 }Little difference between sedative/non-sedative

REVIEWS OF THERAPIES FOR CHRONIC PAIN

Therapy: Antidepressant-Induced Analgesia

AUTHORS(Year)

POP. STUDIED

N QUALITYOFMETHODS

N OFSTUDIESINCLUDED

RESULTS :OUTCOME - EFFECT SIZE

DIRECTION OF EFFECT

Di Fabio R, 1995 Low BackPain

2373 Assessor 1 =Acceptable

Assessor 2 =Acceptable

19 Comprehensive Program vs. BackSchool:

Comprehensive Program, incl.Back School (d = 0.28)Back School (d= -0.18)

} Comprehensive programs were superior to primariy back schoolprograms with respect to pain reduction, increased spinal mobility, andincreased strength

} Work/voactional and disability outcomes were not improved beyondcontrol levels

Inpatient programs (d = 0.32)Outpatient programs (d = 0.01)Outpatient programs providingcomprehensive rehab (d = 0.26)

} Chronicity did not play role in magnitude of effect size

REVIEWS OF THERAPIES FOR CHRONIC PAIN

Therapy: Comprehensive Rehabilitation Programs and Back Schools

AUTHORS(Year)

POP. STUDIED

N QUALITYOFMETHODS

N OFSTUDIESINCLUDED

RESULTS : OUTCOME –SIMPLE COMPARISON

DIRECTION OF EFFECT

Beckerman H, et.al., 1992

Disordersof theMusculo-skeletalSystem orSkinDisorders

1704 Assessor 1 =Acceptable

Assessor 2 =Acceptable

36RandomizedControlledTrials

7 of the Best RCTs:

3 showed positive results2 showed negative results2 the analysis was incorrect

}The results were not pooled because of wide variety of methodologicalquality, heterogeneity of diagnosis, treatment characteristics and outcomemeasurement

REVIEWS OF THERAPIES FOR CHRONIC PAIN

Therapy: Laser Therapy

AUTHORS(Year)

POP. STUDIED

N QUALITYOFMETHODS

N OFSTUDIESINCLUDED

RESULTS :OUTCOME - EFFECT SIZE

DIRECTION OF EFFECT

Hurwitz El, et. al.,1996

Neck Pain:SubacuteandChronic

327 Assessor 1 =Acceptable

Assessor 2 =Acceptable

6RandomizedControl Trials

2 Studies:

RCT - Manipulation andMobilization

3 Studies:

2 RCT – Muscule relaxant vs.Muscle relaxant and manipulation

1 RCT – Manual therapy vs. otherconservative therapies

-pooled effect size 0.42 (-.005,0.85)

1 Study:

RCT – Salicylate and mobilizationvs. other treatments

ς One study showed pain threshold improvement – neither showedconvincing significant changes

ς Non-significant benefit for manipulation

ς Non-significant pain improvement and modestly significant functionalimprovement

ς almost significant effect size for pain relief

ς Mobilization better re pain a 4 weeks (mobility unchanged)

REVIEWS OF THERAPIES FOR CHRONIC PAIN

Therapy: Manipulation and Mobilization

AUTHORS(Year)

POP. STUDIED

N QUALITYOFMETHODS

N OFSTUDIESINCLUDED

RESULTS : OUTCOME –STANDARD MEANDIFFERENCE- (95%CONFIDENCE INTERVAL)

DIRECTION OF EFFECT

Gross AR, 1997b Adults withMechanicalNeckDisorders

271 Assessor 1 =Acceptable

Assessor 2 =Acceptable

3RandomizedControlledTrials:1 RCT ofGroupEducationand 2 RCTsof IndividualTeaching

Group Instruction + Exercise vs.Group Education + PsychologicalCounselling + Exercise:

Group education : SMD = 0.366 ( -0.95, 0.219)Group education + Counselling:SMD = 0.073 ( -0.513, 0.659)

Individual Teaching vs.Individual Teaching + Medication+ Soft Collar.

} did not reduce pain report

} were not found to be more effective than control or placebotreatments (Note – low statistical power)

REVIEWS OF THERAPIES FOR CHRONIC PAIN

Therapy: Patient Education

AUTHORS(Year)

POP. STUDIED

N QUALITYOFMETHODS

N OFSTUDIESINCLUDED

RESULTS : OUTCOME –EFFECT SIZE (S.D.)

DIRECTION OF EFFECT

Malone M, StrubeM, 1988

ChronicPain

Total NotReported

MeanSample

Size= 53

Assessor 1 =Borderline

Assessor 2 =Borderline

48 out of 109 Type of Treatment:

Autogenic 2.74 (1.95)Pill Placebo 2.23 (2.13)Package 1.33 (1.59)Biofeedback 0.95 (1.16)Relaxation 0.67 (0.82)

Outcome Measures:

Symptoms 1.12 (0.40)Mood 1.91 (0.92)EMG Recordings 0.67 (0.40)

} All treatments were successful when compared to no treatmentcontrols. Effect size by cognitive operant conditioning, relaxationand TENS were no larger than the effect size for control conditions.Hypnosis was based on 1 study.

} These three outcomes consistently showed improvement and theleast variability

REVIEWS OF THERAPIES FOR CHRONIC PAIN

Therapy: Non-Medical Treatments

AUTHORS(Year)

POP. STUDIED

N QUALITYOFMETHODS

N OFSTUDIESINCLUDED

RESULTS : OUTCOME –ODDS RATIOS (95% C.I.)% POSITIVE RESPONSE

DIRECTION OF EFFECT

Gadsby JG,Flowerdew MD,1996

Chronic LowBack Pain

288 Assessor 1 =Acceptable

Assessor 2 =Acceptable

6 of 69identified

TENS vs. Placebo: 4 Trials

OR of 1.62 (95% CI 0.90, 2.68)

ALTENS vs. Placebo: 2 Trials

OR of 7.22 (95% CI 2.60, 20.0)

TENS/ALTENS vs. Placebo: 6trials

OR of 2.11 (95% CI 1.32, 3.38)

ALTENS vs. Placebo: 2 Trials

OR of 6.61 (95% CI 2.36, 18.55)

Positive Response:

TENS/ALTENS – 45.5% (39.6% -51.3 %)TENS – 46% (37%, 55%)ALTENS – 87% (80%, 93%)Placebo – 36.4% (28%, 44%)

TENS vs. Placebo: 1 Study:

Functional status

} The use of TENS and ALTENS is more effective than placebo forreducing pain.

ς The use of TENS/ALTENS is more effective than placebo for reducingpain.

ς The use of ALTENS was more effective than placebo forimproving range of motion (ROM).

} Positive response at end of trials.

ς SIP – no significant differences between TENS andSham TENS

REVIEWS OF THERAPIES FOR CHRONIC PAIN

Therapy: Transcutaneous Electrical Nerve Stimulation (TENS) and Acupuncture like TENS (ALTENS)

AUTHORS(Year)

POP. STUDIED

N QUALITYOFMETHODS

N OFSTUDIESINCLUDED

OUTCOME – SIMPLECOMPARISON OFOUTCOMES

DIRECTION OF EFFECT

Beckerman H, et.al., 1993

Musculo-skeletalDisorders

Assessor 1 =Borderline

Assessor 2 =Borderline

180 Trials outof 400RandomizedControl Trials

Most TrialsPoor Quality

31 Trials:Back and Neck PainManipulation

16 Trials:Ultrasound

33 Trials (1592 Patients):Laser

ς 18 studies found positive effectsς 11 studies had negative effects and these studies had highermethodological scores

ς no convincing evidence

ς the efficacy of laser therapy seems to be greater than the efficacy of placebo (no relationship of dose to efficacy)

16 Trials:Exercise (for back pain) vs. otherconservative treatments

Exercise vs. no exercise orplacebo (for chronic LBP)

Comparison of different types ofexercise

16 Trials:-for LBP-for neck pain

18 Trials:-for shoulder

63 Trials:- for knee

ς 2 studies found favorable effectsς 5 studies: exercise no better than comparison condition

ς 1 study favorable effect of exercise < 3 monthsς 2 studies no favorable effect

ς 2 studies – flexion betterς 2 studies – extension betterς 4 studies – no differences

ς 3 best of 16 studies – none showed benefitς all 3 studies showed no benefit

ς of 9 better studies, one showed efficacy (of electromagnetic vs. placebo)

ςς 31 trials shoed positive resultς 32 trials no positive result

REVIEWS OF THERAPIES FOR CHRONIC PAIN

Therapy: Physiotherapy

AUTHORS(Year)

POP. STUDIED

N QUALITYOFMETHODS

N OFSTUDIESINCLUDED

RESULTS : OUTCOME –COMPARISON OFOUTCOMES

DIRECTION OF EFFECT

Koes BW, et. al.,1991

Back andNeck Pain

Assessor 1 =Acceptable

Assessor 2=Acceptable

35RandomizedControlledTrials

18 Studies

5 Studies

4 Studies with 50-60 points (out of 100)

11 Studies

ς favorable results for manipulation compared to referencetreatment

ς reported positive results in one or more subgroups

} 1 = manipulation better 2 = manipulation better in a subgroup 1 = no better than reference treatment

ς manipulation not better than reference. Negative studies tended to be of higher quality

CONCLUSION: results are promising but efficacy still has notbeen convincingly shown. Better studies needed.

Therapy: Spinal Manipulation and Mobilization

REVIEWS OF THERAPIES FOR CHRONIC PAIN

AUTHORS(Year)

POP. STUDIED

N QUALITYOFMETHODS

N OFSTUDIESINCLUDED

RESULTS : OUTCOME –EFFECT SIZE (S.D.)

DIRECTION OF EFFECT

Cohen JE, et.al.,1994

Acute andChronicLow BackPain

903 Assessor 1 =Acceptable

Assessor 2 =Acceptable

6 out of 13 2 Studies:

Acute Low back Pain

4 Studies:

Chronic Low Back Pain

ς In 1 study significantly reduced pain duration and initialsick leave duration in short term compared to placeboς At 1 year follow up, there was no significant evidence ofany clinically important benefits

ςOnly 1 study found a significant positive short term effect onpain intensity compared to placeboς 1 study found significant long-term effect on functional statusand spinal mobility compared to no treatment

ς For both the short and long term, results favored education if comparedto passive or no treatment. Exercise and active treatmentfared better than group education, or group education was not betterthan active control conditions

REVIEWS OF THERAPIES FOR CHRONIC PAIN

Therapy: Group Education Interventions

AUTHORS(Year)

POP. STUDIED

N QUALITYOFMETHODS

N OFSTUDIESINCLUDED

RESULTS : OUTCOME –d = MEAN DIFFERENCES.E. (d) =standard error of difference(95% CONFIDENCE LIMITS)

DIRECTION OF EFFECT

Gam AN, ThorsenH, Lonnberg F,1993

Musculo-skeletal Pain

557 Assessor 1 =Acceptable

Assessor 2 =Acceptable

13ControlledTrials

9 Double Blind RandomizedControlled Trials:d = 0.3% S.E.(d) = 4.6%C.I. = –10.3% – 10.9%

4 Insufficiently Blind Trials:d = 9.45% S.E. (d) = 4.5%C.I. = -2.9% – 21.8%

} no effect on pain in the musculoskeletal system

REVIEWS OF THERAPIES FOR CHRONIC PAIN

Therapy: Low-Level Laser Treatments

AUTHORS(Year)

POP. STUDIED

N QUALITYOFMETHODS

N OFSTUDIESINCLUDED

RESULTS : OUTCOME –EFFECT SIZE (S.D.)

DIRECTION OF EFFECT

Spitzer et al, 1987 LBP &CervicalPain

Assessor 1 =Acceptable

Assessor 2 =Acceptable

RCT = 84 (14very good, 33good)

ControlledStudies = 116(15 very good,40 good)

DescriptiveStudies = 157 (8 very good,38 good)

Reviews = 112(13 very good,38 good)

Acute low back pain with orwithout radiation

LBP over 7 weeks including LBPradiating to thigh and calf:Systemic medicationElectroanalgesiaStrengthening exercisesPostural information andfunctional training (if idle)Modification of work environment

LBP with radiation andneurological signs over 7 weeks:Systemic medicationElectroanalgesiaPostural information andfunctional training (if idle)

Chronic pain syndrome:Systemic medicationElectroanalgesiaStrengthening exercisesPostural information andfunctional training (if idle)Modification of work environment____In 1987, less evidence on neckpain

ς RCTs confirm utility of < 2 days bed rest for LBPwith/without leg radiation and utility of longer bed rest andradicular compression confirmedς RCTs confirm back school is helpfulς Controlled studies: systemic medication helpful for 7 days orless back pain

ς TENS helpful for back pain > 7 weeks, by controlled studiesς Strengthening exercise helpful for LBP over 7 weeks

ς Education appropriate for LBP > 7 weeks

ς Functional training and ergonomic intervention for LBP >7 weeksς Education appropriate, by controlled studies

ςConclusion re neck pain treatment similar to above, but with less evidence in 1987

REVIEWS OF THERAPIES FOR CHRONIC PAIN

Therapy: Therapies for Low Back Pain

UNACCEPTABLE TRIALS AND/OR REVIEWS:RATINGS OF QUALITY OF METHODS

AUTHORS (Year) POP. STUDIED QUALITY OFMETHODS

THERAPY

Guthrie E, 1996 Chronic Illness Assessor 1 =Unacceptable

Assessor 2 =Unacceptable

PsychotherapeuticInterventions

Pollmann W, Keidel M,Pfaffenrath V, 1997

Headache and theCervical Spine

Assessor 1 =Unacceptable

Assessor 2 =Unacceptable

Manual DiagnosticFindingsDifferential DiagnosisTreatments

Feine J, Lund J, 1997 ChronicMusculoskeletal Pain

Assessor 1 =Unacceptable

Assessor 2 =Unacceptable

Multiple PhysicalTherapies, includingUltrasound and ThermalAgents, Acupuncture,Low Intensity Laser,TENS, Manipulation,Stretching, and Exercise

AUTHOR STUDYQUALITY

N(underline iscondition,non-underline iscomparison)

DIAGNOSES PAINDURATION

STUDYDESIGN

INTERVENTION DURATIONFOLLOW UP

RESULT (Measure)

Garvey et al(1989)

5 63(13, 14, 20,16)

LBP Acute?> 4 wks

RandomizedDouble Blind

Lidocaine 13Vs.

Lidocaine &cortisone

Vs.Acupuncture 20

Vs.Vapocoolant 16

2 wks (self-reported improvement)non-invasive treatment as effective asinjection therapies

Hong (1994) 2 58(35, 23)

Trapezius TPs 1 – 24 wks ? Randomized TP lidocaine 26TP dry needle 15

No twitch 17

Post-treatment2 wks

(local twitch response, self-reportedpain, dolorimeter, cervical lateralbending)No difference in lidocaive vs. dryneedling on dolorimeter or ROMDry needling more painful thanlidocaiveNo benefit unless local twitch evoked

Lilius et al(1989)

3 109(28, 39, 42)

LBP .> 3 mos. ? Randomized

Rater blindand patientblind

Lidocaine,bipivucaine &

cortisone into facets28Vs.

Bipivucaine &cortisone around

facets 39Vs.

Saline into facets 42

1 hour

2 wks, 6 wks,and 3 months

(work attendance, pain self-report,VAS, lumbar movement [observerrated], disability [observer rated,unstandardized])Improvement generally on allmeasures for all groups but nosignificant differences between groups

Marks et al(1992)

3 86(42, 44)

LBP 0.7-35 yrs(median 10 yrsexper. group &7 yrs controlgroup)

RandomizedDouble Blind

Lidocaine &cortisone to facets

42Vs.

Around facets 44

Immediate2 weeks1 month3 months

(self-reported pain – on movement)facet blocks minimally better at allpoints but significant only at 1 month

AUTHOR STUDYQUALITY

N DIAGNOSES PAINDURATION

STUDYDESIGN

INTERVENTION DURATIONFOLLOW UP

RESULT (Measure)

Bourne (1984) 3 57(30, 19)

CLBP Chronic ? RandomizedSingle blind

Cortisone &lidocaine

Vs.Lidocaine

2 wks & 3mos.

(duration, pain relief)Cortisone & lidocaine sign. better thanlidocaine (3 mos)

Byrn et al(1993)

3 40(20, 20)

Whiplash 4-6 yrs RandomizedNot blind

SalineVs.

Sterile Water

Immediate1 mos.3 mos.8 mos.

(pain, VAS, ROM °, self-reportedimprovement)-sterile water improved immediately inVAS and ROM °-sterile water improved in all measuresat 3 mos.-sterile water better at 8 mos. in ROM°and VAS

Carette et al(1991)

5 97(49, 48)

CLBP Chronic,median 18 to24 mos.

RandomizedDouble blind

CortisoneVs.Saline to facet joints

1 mos.3 mos.6 mos.

(pain: VAS, McGill)(function: SIP, limitation, trunkflexion)No signif. Differences at 1 & 3 mos.At 6 mos., cortisone group did better reVAS, self-report & physical disability)

Collee et al(1991)

3 41(21, 20)

Iliac crestsyndrome(low back pain)

Rheumatologygroup 8 yrs.

Generalpractice group18 days

RandomizedDouble blind

LidocaineVs.

Saline

0 days7 days14 days

(pain score self-report & % patientsimproved)Rheumatology, but not generalpractice patients, significantlyimproved on both measures at day 14on lidocaine vs saline

Frost et al(1980)

4 53(28, 25)

“Muscle Pain” Acute RandomizedDouble blind

MepivucaineVs.

Saline

Up to 2 wks. (pain self-report, satisfaction, reliefduration)pain relief duration favored saline overmepivucaine (short lived).Other measures no differences

AUTHOR STUDYQUALITY

N DIAGNOSES PAINDURATION

STUDYDESIGN

INTERVENTION DURATIONFOLLOW UP

RESULT (Measure)

Ongley et al(1987)

5 81(40, 41)

LBP Avg. 10 yrs.(1-35 yrs.)

RandomizedDouble blind

6 weekly injections:injecting proliferant

solution &cortisone, &lidocaine &

manipulation 40vs.

injecting saline, &lidocaine &minormanipulation 41

All patients hadexercise instruction

Baseline, 1, 3& 6 months

(disability scores, VAS pain, paindrawings)(validated disability scales)-on all measures, outcomessignificantly better in experimentalgroup at 1,3 & 6 months

Sonne et al(1985)

3 30(14, 15)

LBP > 1 month RandomizedDouble blind

3 weekly injectionsto iliolumbar

ligamentvs.

lidocaine &cortisone

vs.saline

2 weeks (VAS, spinal flexion, self-assessment)Lidocaine & cortisone significanlybetter in VAS pain & self-assessment

Wreje &Brorsson (1995)

3 116(55, 61)

MyofascialUpper body

All > 3 months

80% > 1 yr.

RandomizedDouble blind

Sterile water 55Vs.

Saline 61

Immediate &2 wks

(VAS)No significant difference

1

APPENDIX 2

PROGNOSTIC FACTORS: A CONCISE SUMMARY

Prognositically important variables identified from the literature are summarized underthe following headings:

Sociodemographic factors: age, gender, education, SES, MS

Work factors: type and size of employing company; physical demands of the job;work satisfaction; control of pace of work; length of time out of work; availability ofa job; ease of changing occupations and modified work.

Impairments:Pain – site of symptoms; number of painful sites/wide area of body; pain grade(based on pain intensity and disability days); pain behavior;Physical Impairment Factors – health status; fatigue; sleep disturbance; previousepisodes;Psychological Impairment Factors – depression; cognitive factors (catastrophizing);coping factors; alcohol/drug abuse.

Disabilities:Disability Factors – functional status; ADL capacity;Social Support Factors – change in marital satisfaction post-pain onset; decrease insocial activities; financial and social strain.