Journal of Back and Musculoskeletal Rehabilitation Journal of Back and Musculoskeletal Rehabilitation 5 (1995) 135-144
The role of rehabilitation medicine in the management of chronic pain: description of a pain control program and longitudinal outcomes J.S. Richards*, C. Nepomuceno, A. Buell, V. Wadley, D. Blackmon University ofAlabama at Birmingham, Birmingham, AL, USA
Longitudinal outcomes of 35 patients with chronic benign pain were studied following their participation in a 3-week multidisciplinary pain management program. Pretreatment status with respect to activity levels, health care utilization, medication use, and subjective pain intensity was compared statistically with post-treatment status at three follow-up assessments (discharge, 1.6 months, and 22.7 months post-discharge). Results suggest a positive impact of treatment on activity levels, health care utilization, and medication use post-discharge, with diminution of that impact over time. Pain management programs increasingly will need to demonstrate cost effectiveness, including finding ways to maximize program gains over time.
Keywords: Chronic pain; Rehabilitation; Longitudinal outcome
1. Introduction The understanding of chronic pain has increased significantly in the last 20 years. However, despite this expansion of knowledge, it remains apparent that chronic pain is a complex problem and that effective treatments for patients suffering from chronic pain are elusive. Physicians are programmed from the beginnings of their careers to consider pain - be it acute or chronic - as a symptom of a disease that must be diagnosed and
* Corresponding author.
cured. This perspective fails to regard acute and chronic pain as two distinct clinical entities. The treatment principles used effectively to cure acute pain seldom apply to chronic pain and sometimes in fact are contra-indicated in it's management. Unless the concept of chronic pain management or control (in contrast to cure) is understood, accepted and practised, we will continue to see many unhappy patients in chronic pain. This problem will remain among medicine's greatest failures, affecting 30-40 million individuals in the United States and costing our economy 50-90 billion dollars a year . The definition of chronic pain continues to be
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ambiguous. Does acute pain become chronic simply with passage of time, or does acute pain become chronic whenever it persists beyond an expected time allowance for healing? The inadequacy of these conceptualizations is implicit in the lack of agreement on a point in time at which acute pain crosses an arbitrary threshold into chronicity (e.g. 3 weeks, 3 months, or 6 months). There are four characteristics of chronic pain that distinguish it from acute pain. First, the pain no longer serves the physiologic function of signalling impending or actual tissue damage. Pain ceases to be a "Y!l1pl ..}m ot disea:;e or pathology and over time more closely resembles a conditioned response . Second, emotional distress is associated with chronic pain. It has been estimated that as many as 90% of chronic pain patients have significant emotional problems . Often, anxiety is manifested early on and, up to a point, is considered appropriate. However, in those with chronic pain, anxiety characteristically is replaced by depression. Third, chronic pain becomes a disease entity in its own right, with its own constellation of signs and symptoms. Fractures heal, herniated discs are resected, and injured nerves mend. Nonetheless, the pain persists. Lastly, chronic pain becomes regarded as incurable and its resolution becomes an elusive goal. Many principles in the management of chronic pain are based on these four characteristics. Several levels of care for patients with chronic pain have emerged. The first 'line of defense' is the block clinic. These typically operate on an outpatient basis, supervised by an anesthesiologist whose aim is to eliminate pain with a variety of local anesthetic and/or steroid injections. However, such blocks often work only temporarily . For the patient who does not respond to this form of treatment, more in-depth evaluation and management of chronic pain may be available. Implemented on an in- or out-patient basis, intensive evaluation and management may include the entire diagnostic and therapeutic spectrum including surgical intervention. However, the large number of patients who continue to endure chronic pain following such procedures suggests the ineffectiveness of this approach. Once chronic pain has been unresponsive to the gamut of avail-
able curative treatments, the strategy must shift from cure to control. From this point on, rehabilitation strategies become the basis for the management of chronic pain. Although many clinicians traditionally have been reluctant to accept the concept of pain control, the concept is gaining widespread acceptance as an alternative to more conventional medical and surgical treatment of chronic pain. No one individual is sufficiently trained to meet the multifaceted problems of patients with chronic pain. Thus, the structure and approach of pain control programs should be multidisciplinary . Pain control programs adopting a multidisciplinary approach may be implemented either on an in- or out-patient basis. Program specifics may be adjusted to meet individual needs. A Pain Control Program was developed in 1978 at the Spain Rehabilitation Center, the hub of rehabilitative activities at the University of Alabama at Birmingham (UAB) Medical Center. Criteria for admission include the presence of chronic pain, a doctor's referral, voluntary participation, and family commitment. The pain control 'team' consists of a case manager, an attending psychiatrist, clinical psychologist, physical therapist, occupational therapist, recreational therapist, social worker, nurses, the patient, family members, and any adjunct health personnel who may be called upon as needed during the patient's hospitalization. As is reflected in the diversity of its team members, the Pain Control Program incorporates a variety of therapeutic modalities and is carried out over a 3-week period. Exercise is one primary focus of treatment. Patients often have become sedentary and sometimes have gained considerable weight and become deconditioned to the extent that they are unable to perform even the lightest of physical work. Gradually increasing in its demands, the exercise program is intended to tone muscles, increase agility and physical strength, and limber joints. Patients with chronic pain often have come to equate physical activity with discomfort and pain. Before admission to the program, many patients are unable to sit or stand for more than a few minutes at a time. Therefore, the patients' activity
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tolerance gradually is built up to 60 min each day of sitting and standing, 3 miles of walking, and 6 miles of biking (average) at discharge. Patients are given opportunities to demonstrate their acquired tolerance of activities' in the presence of other program participants, family members, and staff. Training in progressive muscle relaxation  (and other relaxation techniques) is another component of the Pain Control Program. Back muscles are stiff from muscle spasm and can serve as a source of persistent pain. Patients also are instructed in proper posture and body mechanics to prevent pain exacerbations due to repeated restraining of their necks and backs. Patients learn techniques for transferring in and out of beds and cars, for picking up things from the floor, for lifting weights, and so on. They become aware of proper protection of the spine. The subjective experience of pain is often accompanied by behaviors that can be observed, measured, and modified by environmental contingencies. Using the UAB Pain Behavior Scale , the pain-related behaviors of an individual can be recorded. Among many methods of behavior modification, positive reinforcement is the simplest and the most effective. In essence, 'sick' behaviors are ignored by staff and 'well' behaviors are recognized. These 'well' behaviors are rewarded with praise, public recognition, smiles from staff, etc. Patients with chronic pain often have ineffective self-management strategies. A cognitive-behavioral component of the Pain Control Program focuses on faulty thinking about pain and its meaning; for example, patients are discouraged from 'catastrophizing' about their pain. They are counseled not to see themselves as disabled by their pain. Participants are encouraged to discard unnecessary supportive devices such as canes and braces and to decrease utilization of other external sources of help, such as excessive health care seeking. The central goal of the pain control team is to prove to persons with chronic pain that pain and other bodily ailments are not deterrents to meaningful and productive lives. Many patients with chronic pain have misused or abused analgesics and psychotropic medica-
tions . Although dependence on such drugs is common, true addiction is rare. By the time patients get to the third stage of chronic pain management, they often are confused about medication usage and management. Many are misinformed and some feel gUilty about the drugs they do take. Many pain centers use 'pain cocktails' and placebos but, in our experience, the most effective way of improving patients' medication knowledge is to explain the risks of taking drugs in easily understood terms. A detailed plan may be presented on how to manage drug intake. The clinician who is confident and knowledgeable, who sincerely wants to help, and who will not desert the patient should have no problems convincing the patient to take medications as prescribed. Drug management should include simplification of the medication regimen, avoidance of narcotic analgesics and injections, and time-contingent drug administration. Inadvertent reinforcement of chronic pain by patients' family members is another focus of attention in the Pain Control Program. Secondary incentives for patients' failure to improve from the chronic pain syndrome among others may include attention, financial reward, companionship, and control. Family education and counseling are thus essential parts of the pain control program. Because the nature and persistence of chronic pain is seldom understood by families, family education can help dispel confusion about chronic pain and guide families toward support of wellness rather than disability. For example, many people have little understanding of normal degenerative changes caused by aging. Based on the principle that "knowing the problem is half-way solving it," patients and families are given a series of didactic lectures presented by members of the pain control team. These lectures include discussions of pain control, fundamental anatomy and applicable physiology of pain, medical and psychological aspects of pain, pacing, assertiveness, stress management, disability, and secondary incentives. Although the consensus among professionals who work with individuals with chronic pain is that something must be done to manage pain and enhance quality of life, the efficacy of treatment
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programs all too often is not evaluated. Before program efficacy can be evaluated, however, successful outcomes must be defined, and this is no small problem. A reduction in the subjective experience of pain is one obvious outcome measure. Meta-analyses of studies in which subjective ratings of pain intensity have been incorporated as outcome measures reveal that these ratings generally have improved at the time of program discharge and have been maintained over followup periods of up to 3 years [9,10]. Flor and colleagues  caution, however, that many studies included in. these meta-analytic reviews are plagued by limitations in design and methodology and therefore must be interpreted with care. Turk et al.  urge consideration of the clinical importance of statistically significant reductions in pain and also suggest inclusion of patient satisfaction with program benefits as a meaningful outcome variable. Return to work, reduced health care visits and costs, reduced use of addictive medications, and increased involvement in functional and recreational activities are pragmatic outcome variables that concern individuals with chronic pain and the professionals who work with them. Demonstrable success in terms of economically relevant measures, in particular, assumes increasing importance that parallels the increasing importance of third-party reimbursement. An additional consideration in defining program effectiveness is the maintenance of any gains that are made immediately post-treatment. Even among programs in which treatment outcomes are evaluated, those outcomes generally have not been evaluated beyond discharge or, at best, not beyond a 2- or 3-month follow-up . Exceptional studies have assessed outcomes at follow-ups ranging from 18 to 30 months [12-14]. The purpose of this study is the longitudinal assessment of relevant outcomes among a sample of participants in the Pain Control Program at Spain Rehabilitation Center. 2. Methods Routine clinical follow-up is carried out 1-2 months post-discharge and a number of outcome measures are recorded at that time. For purposes
of this study, additional variables were developed to assess long-term outcomes. The resulting long-term outcomes questionnaire was pilot tested and revised and then administered to all available patients who had successfully completed the pain control program at least 1 year previously. Instructions emphasized the confidential nature of responses and the need for frank replies to questions; it was emphasized that this was an attempt to evaluate the effectiveness of the pain control program and frank answers were important. This was done in order to minimize social desirability responding. The 35 participants included in this report were selected on the basis of their availability at the T2 assessment. At T2, contact by mail and telephone was attempted with 57 consecutive patients who completed the SRC Pain Control Program from August 1987, through March 1992. Of these 57, 36 (63%) were contacted. Those not contacted included 13 former patients with disconnected or unlisted telephone numbers, four who failed to return telephone messages, four who had moved with no forwarding address, and one who was deceased. Of the 36 patients located at T2, one patient declined follow-up because his home had recently been destroyed by fire. The remaining 35 who agreed to participate in follow-up assessment compose the longitudinal sample. Discharge information on these 35 participants were objective measures obtained from their charts. Tl data were obtained only from those 20 among the sample of 35 (57%) who attended scheduled clinical evaluations at SRC 1-2 months post-discharge. 3. Results Thirty-five participants were assessed at baseline TO (or pretreatment) and again at T2 (M = 22.67 months post-discharge). At the interim assessment T1 (M = 1.60 months post-discharge), 20 participants were contacted. On selected variables (miles walking and biking daily, hours spent in 'down time' daily, and pain intensity ratings) objective discharge data were obtained by examining patient charts. The number of participants on whom such data were available varied
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from 24 to 30, depending on the measure in question. A description of the patient sample is presented in Table 1. Females were disproportionately represented (66%); patients averaged 48 years of age. Most (77%) listed low back pain as their primary complaint and had experienced chronic pain for an average of 8.15 years (S.D. 8.96). Twenty-five (71%) had undergone at least one surgical intervention for pain (M = 1.43, S.D. 1.57); 10 had no prior surgeries. All but one participant had been unemployed for an average of 5.08 years (S.D. 5.97) prior to entering the program. Most were either receiving compensation (58%) related to pain or had a pending claim (15%) at the time of entry into the program. In
short, this was very much a chronic pain sample who had failed conventional medical and surgical methods and who had become entrenched in a disabled lifestyle. 3.1. Patient satisfaction
Patient satisfaction was measured with three questions at T2 only. First, each participant was asked, "overall, was the program worth your time?" Twenty-eight participants (82.4%) responded "yes," six (17.6%) responded "no," and one participant did not answer the question. Second, participants were asked, "would you recommend the program to friends or family with chronic pain?" Twenty-nine participants (82.9%) responded "yes," five (14.3%) responded "no,"
Table 1 Demographic and descriptive data for the sample N
Gender Male Female
Race African American White
Marital status Single Divorced Widowed Married
2 7 2 24
5.7 20.0 5.7 68.6
Pain site Multiple / diffuse Low back pain Neckpain
5 27 3
Pain duration Number of years
Compensation (at TO) None Claim Pending Receiving
9 5 19
14.3 77.1 8.6
27.3 15.2 57.6
a number of years unemployed was calculated only for participants who were previously employed and not past retirement age. (Source: author.)
1.S. Richards et al.II Back Musculoskelet. Rehabil. 5 (1995) 135-144
and one (2.9%) responded "yes and no," qualifying the recommendation on a case-by-case basis. Third, numerical ratings of the program were solicited on a 0-10 scale, with 0 representing "terrible," 10 representing "excellent, couldn't be improved," and 5 representing "half-way between." The mean rating of the program was 7.76 (S.D. 2.76). 3.2. Pain ratings Pain was rated upon admission to the Pain Control Program: TO (at discharge), at Tl, and at T2 on a scale of 0 (no pain) to 10 (extreme pain). Mean ratings are depicted in Fig. 1. Post-hoc comparison of means at discharge and admission were conducted using Student's t-test to determine whether mean changes were significantly different from zero. Mean ratings were significantly lower at discharge than upon admission, (T = - 2.52, P < 0.02). However, there were no significant differences between TO and T1 or TI. 3.3. Health care utilization At each assessment period (TO, T1, and T2), participants reported the number of pain-related doctor visits, emergency room visits, and days hospitalized during the month prior to that assessment. Two repeated measures multiple analyses of variance (MANOVAs) were conducted to determine the multivariate and univariate effects of time (pretreatment, post-discharge, and long-term follow-up) on doctor visits, emergency room visits,
Fig. 1. Pain ratings over time. P < 0.02 in comparison to admission. (Source: author.)
and hospitalizations. One MANOVA examined the effects from TO to Tl and the other from TO to T2. This procedure was followed due to the reduced number of participants contacted at T1. Separate MANOVAs allowed inclusion of all viable cases in the analyses. Each model resulted in a significant overall time effect (F(3,17) = 6.08, P < 0.004, from TO to Tl, and F(3,32) = 4.64, P < 0.005, from TO to T2). In each case, the multivariate effect was due to significant decreases in the number of doctor visits during the previous month: comparing Tl and TO (F(1,19) = 19.65, P < 0.0003), and comparing T2 and TO, (F(1,34) = 12.22, P < 0.002) (see Table 2). Only one subject reported having been hospitalized for pain-related problems (4 days) during the month prior to admission (TO); no subject had been hospitalized during the month preceding assessment at T1; and seven subjects had been hospitalized (ranging from 1 to 7 days) during the month prior to assessment at T2. The low frequency of hospitalizations among subjects should be considered when examining the mean number of days spent hospitalized reported at each assessment period. 3.4. Medication use Changes in medication use were determined by first classifying each medication as either narcotic or non-narcotic (including psychotropic, anti-inflammatory medications, etc.). Subjects taking no medication were grouped with those taking nonnarcotic medications for the purpose of these analyses. Chi-square analyses revealed a significant reduction in the percentage of participants taking narcotic medications upon discharge from the program compared with TO (see Table 2). Respondents still reported less use of narcotics for pain management at T2 than was the case upon admission, but this difference did not reach statistical significance. 3.5. Surgeries The number of surgical procedures for pain post-discharge was assessed at TI. Only two participants had undergone surgery for pain problems post-program; each had one procedure.
1.S. Richards et al.; 1. Back Musculoskelet. RehabiL 5 (1995) 135-144
Table 2 Longitudinal outcomes: health care utilization, activity levels, and medication use
T1 (n = 20)
T2(n = 35)
No. in previous month:
Doctor visits Mean S.D. Emergency room visits Mean S.D. Days hospitalized Mean S.D.
No. hours per day
Volunteer work Mean S.D. Household chores Mean S.D.
TO(%) (n = 35) Medication use (%) None or non-narcotic Narcotic
Discharge (n 74.3* 25.7
*x 2 for difference in percentage using no medication or non-narcotic medication vs. narcotic medication at TO and at discharge, P < 0.05; ** P < 0.01, comparing T2 and TO; *** P < 0.001, comparing T1 and TO. (Source: author.)
3.6. Activities Participation in a variety of activities was assessed at baseline and at each follow-up. First, the amount of inactivity due to pain was assessed. Participants reported the average number of hours of 'down time' they spent between 8 a.m. and 8 p.m. each day during the previous month. 'Down time' was defined as time spent lying down to cope with pain. The average number of miles per day walked and biked during the previous month were also reported, as were the average number of hours per day spent carrying out household responsibilities and doing volunteer work during the previous month. As with the health care measures, two repeated measures MANOVAs were conducted to determine the multivariate and univariate effects of time (pretreatment, post-discharge, and long-term follow-up) on the activity variables. Biking was not included in these analyses due to the low number of subjects who reported biking prior to
program admission. The first MANOVA examined the effects from TO to Tl and the second examined the effects from TO to T2. Due to missing data, the former model included 15 subjects with complete data and the latter included 28. Again, separate MANOVAs were computed to allow inclusion of all viable cases at each assessment. Each model resulted in a significant overall time effect (F(4,1l) = 7.83, P < 0.004, from TO to Tl, and F(4,24) = 4.15, P < 0.02, from TO to T2). The multivariate effect of time in the TO-Tl model was due to significant decreases in down time (F(1,14) = 12.14, P < 0.004) and significant increases in miles walked per day (F(I,14) = 31.53, P < 0.0001) and hours spent per day in fulfilling household obligations (F(I,14) = 17.55, P < 0.0009). In the TO-T2 model, the multivariate effect was due to a significant increase only in miles walked (F(I,27) = 5.65, P < 0.03). Post-hoc comparisons of both down time and miles walked
I.S. Richards et al. / I. Back Musculoskelet. Rehabi/. 5 (J995) 135-144
... r-=------- ----------4.1
t·· . .. . ... . .... '.....
....... ::··:::::·:::·········:······1 ·····1
Fig. 2. 'Down time' over time (hours per day spent lying down for pain relief). *P < 0.005; ** P < 0.0001, comparisons to admission. (Source: author.)
at discharge and upon admission revealed significant decreases in down time at discharge (T = - 6.18, P < 0.0001), and significant increases in walking at discharge (T = 10.37, P < 0.0001) (Figs. 2, 3). Again, due to the low number of participants who had bikes prior to admission, biking data were not analysed using TO as a baseline.
3. 7. Exercise Continuation of exercise regimens undertaken during program participation was assessed at T2 only. Twenty-two participants (62.9%) reported continuing their exercises, 12 (34.3%) reported having discontinued their exercises, and one participant (2.9%) qualified his response, having continued with exercise until a recent acute injury.
... .... ... 2.0
3.B. Work / disability status Participants reported at all three times the average number of hours per day they had worked at a 'dollar-earning job' during the previous month. At TO only one participant had been employed during the preceding month; that subject worked 8 h per day. At both T1 and T2, no ~articipant had worked during the month precedmg assessment.
~.. ~i--------~~.-~---·---.....-,---------..... ~.
Fig. 3. Physical activities over time (miles per day walking and biking). *P < 0.005; ** P < 0.0001, comparisons to admission. (Source: author.)
4. Discussion Providing effective treatment for persons as entrenched in disability as was this sample is a daunting task. Patients in this sample had been injured for a number of years, most had undergone one or more unsuccessful surgeries, and most were receiving or awaiting receipt of monetary compensation for their pain and subsequent disability. In short, in contrast to persons with more recent onset pain, this is the most difficult type of chronic pain patient to treat. Perhaps the biggest difficulty is that while significant gains can be made in the short-term, particularly within the confines of the hospitalization or program itself, a reduction in benefits is often seen over time. This was seen in our sample as well. Chronic pain treatment programs need to carry out long-term follow-up of patients in order to get a more realistic assessment of the impact of treatment than is apparent if only very short-term benefits are examined. How one attempts to measure benefit is a matter of considerable debate. It could be argued that ours was a largely successful endeavor for the great majority of these patients if success is measured by patient satisfaction and ratings of program efficacy. However, examination of other types of indices, such as activity level and health care utilization, suggests more modest success, particularly in the long-term. Certain encouraging trends in health care utilization were suggested among our relatively small sample; had the sample size been larger, these trends might have e?Ierged as both statistically and clinically sigmficant effects (for example, long-term mainte-
J.S. Richards et af. /1. Back Musculoskelet. Rehabil. 5 (J995) 135-144
nance of reduced narcotics use). A reduction in doctor visits for pain was maintained over time, a benefit reflective of a major emphasis of the program: increasing reliance on self-management rather than 'other' management methods. The fact that very few patients in this series underwent additional surgery in the 2-year average follow-up period also may reflect a positive cost benefit, since considerable emphasis is placed in the program on the diminishing returns of repeated surgery. It is acknowledged that our sample size in several cases is small for statistical procedures like MANOVA. Multiple separate analyses of variance or t-tests could have been conducted instead, but it was felt that such a statistical approach would have increased the probability of detecting false positive results. We chose to document change in most measures by using a I-month time period prior to each point of inquiry. It could be argued that a longer period of time would have been more effective to analyse (for example, analysing health care utilization for the entire year prior to admission rather than the prior month). However, it has been well established that accuracy of recall is enhanced when shorter time periods are measured. Since we relied on patient recall, we felt that using a I-month window would be more accurate. The best option, of course, would have been to obtain data on the actual costs incurred in health care utilization. However, obtaining such data is extremely difficult, time consuming, and expensive; this option was well beyond the resources of the present investigation. Nevertheless, third-party payors may increasingly require such documentation of pain treatment efficacy before agreeing to cover the costs of such treatment. Return to work rates as a function of treatment were disappointing; only one of our 35 patients had been working prior to treatment and none were in fact working at the end of the 2-year average follow-up span. The legal, financial and attitudinal barriers to successfully returning to work for patients with such an extensive chronic pain history have been well documented and suggest that for this particular very chronic sample, return to work probably was not a realistic goal.
Improvements seen at discharge by persons treated for chronic pain are rarely completely maintained at follow-up, particularly long-term follow-up. The reasons for a reduction in benefits over time are myriad and complex and have been discussed widely in the chronic pain literature. New mechanisms for attempting to maintain program gains over time need to be explored. Efforts might include brief monthly or quarterly day-long 'booster' treatment days or increased utilization of pain support groups. The barriers to these and other kinds of treatment innovations tend most often to be financial, but geographic barriers also can be problematic. Furthermore, while pain support groups are potentially beneficial, they can be counter-productive if they arc allowed to become opportunities to focus even further on pain and suffering. Treatment of chronic pain has become a major component of this country's health care costs. Those of us who treat persons with chronic pain need to find multifaceted ways of documenting program effectiveness, which includes delineating factors that would predict poor treatment outcome. In general, it is likely to be more profitable to treat patients with persistent pain sooner rather than later. While some with more acute injuries and subsequent pain might improve without treatment, predicting which individuals are likely to do so is extremely difficult. Early intervention has the best probability for minimizing the 'institutionalization' in the patients' homes of patterns, habits, and expectations of disability and suffering - mechanisms that become extremely difficult to counter with the passage of time. Acknowledgements
M.J. DeVivo, Dr.P.H. for assistance with statistical analyses. References 
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