“Whenever I see my doctor for another visit; he seems to do the Michael Jackson moonwalk—I can feel him backing out of the room at the same time he is walking in”. Patient with chronic pain.
This patient’s (probably accurate) perception captures the frustration of both healthcare providers and patients facing chronic low back pain (CLBP). This subjective impression of being “stuck” is reflected in the continued suffering and disability despite the high cost of ongoing healthcare. As evidenced by recent reports by the Institute of Medicine [1
], between $560 and $630 billion is spent annually on direct and indirect costs of chronic pain. These costs continue, or may in fact increase, despite advancements in pain medicine, in new pain medication, assessment of genotypes predicting medication response [3
], and new surgical and interventional procedures and devices, among others. As the most common type of musculoskeletal pain, low back pain continues to be a primary source of disability, as evidenced in both emergency department and inpatient medical stays [4
In an effort to better understand the problem of CLBP, some have suggested that the problem is more accurately understood and more effectively treated by use of a biopsychosocial model [5
]. The biopsychosocial understanding of pain suggests that perceived pain and ensuing disability result from a complex array of factors interacting over time. This model suggests that success in the treatment of chronic pain is diminished by a simplistic focus on medical intervention for nociception. In fact, some recent literature indicates that CLBP is processed differently than acute back pain [6
]. The present article will review basic biopsychosocial issues impacting chronic low back pain, the use of interdisciplinary programs as an appropriate treatment, and the results of a large prospective series of patients treated with this type of program.
1.1. Psychosocial Factors
The role of psychosocial factors has been well documented in both the development of CLBP and the resulting disability. These factors have been found to increase risk for acute low back pain developing into chronic pain, and for increased risk of disability associated with low back pain [7
]. In addition, these factors adversely impact outcomes of both surgical intervention as well as success of interventional technologies such as spinal cord stimulation or intrathecal pumps for pain control [10
A variety of psychosocial factors have been found to be of relevance [8
]. Clinical assessment often examines an array of factors [11
]: contextual factors such as work related factors, co-occurring life stressors, financial and social reinforcement for pain behavior and disability, and patterns of medical practice, all of which impact outcomes. Other factors evaluated include psychosocial factors such as depression and anxiety, as well as patient expectations, fear of movement (kinesiophobia), reactivity to pain such as pain catastrophizing, and external locus of control. Information is often obtained through both interview and psychometric testing.
In light of data indicating the impact of a biopsychosocial model, interventions based on these factors are used with varying degrees of frequency and have become commonly recommended [15
]. The most common nonsurgical or non-medication intervention has been physical therapy with most patients being prescribed therapy at some point in their treatment. A second well-established approach has been cognitive behavioral therapy (CBT) to address the psychosocial factors. [17
1.2. Interdisciplinary Pain Management Programs
In light of the interactive nature of many factors using the biopsychosocial model, one response has been the development of the interdisciplinary pain management program [19
]. To address this complex array of factors, interdisciplinary pain programs began to appear in the United States initially led by John Bonica. Over the last 40 years, such pain programs have been created throughout the United States. These programs have been described by a primary accreditation organization, CARF International. They define a program in this way: “An interdisciplinary pain rehabilitation program provides outcomes-focused, coordinated, goal-oriented interdisciplinary team services”. p.12 [20
]. They include goals such as a reduction of impairment and activity limitations, while maximizing quality of life.
These programs include multiple types of providers (physicians, psychologists, nurses, occupational therapists, physical therapists) offering coordinated services “under one roof”, with frequent communication through team meetings around a unified vision and goals. They utilize standardized measurement of functioning of physical ability, pain and suffering, emotional distress, utilization of medical resources, and functional activities of living. The model emphasizes the use of structured supervised physical activation with treatment to change behavioral and social patterns which have evolved from, and have changed, the patients’ experience of pain as well as their life functioning. Treatment is designed to address the array of factors impacting patients’ pain, distress, and subsequent disability. It is interesting that some of these factors are ones found by Pincus [8
], which predict chronicity/disability in prospective cohorts with low back pain.
Over the last 30 years, the effectiveness of these programs has been extensively examined for both treatment efficacy and cost-effectiveness [19
]. Fullen et al
] documented effectiveness of treatment of 553 patients with pain over an 8-year period of time. Chou and colleagues in 2009 [28
], in the American Pain Society’s Guidelines for Low Back Pain, gave a “strong” recommendation for the use of interdisciplinary treatment and rated evidence as “high” quality. More recently, a Cochrane System Review and meta-analysis found moderate-quality evidence of programs reducing pain and disability [29
]. When clinical efficacy and cost efficacy of interdisciplinary pain programs were compared to conventional treatment [23
], the programs resulted in greater pain reduction, medication reduction, reduction of emotional distress, decreased health care utilization, reduction of iatrogenic consequences, increased activity/return to work, and closure of disability claims. These same reviews compared cost of interdisciplinary programs to surgical intervention, and conventional care including the cost of initial treatment, subsequent surgery, medical treatment in the year following, and lifetime disability. Interdisciplinary treatment was found to be nine times more cost-effective than conservative treatment. Some studies have documented the economic cost of patients being placed on waitlists for interdisciplinary pain facilities [24
]. In addition to these group changes, Federoff et al.
] documented the efficacy of programs at the level of individuals, rather just on a group basis. Significant variability was found in response to treatment, but no clear predictors of response were found. In an extension of work by Morley [32
], Smith et al.
] repeated an analysis of both group and individual response. They also found that outcomes changed when outcomes from two different time sequences were compared.
Several issues warrant further exploration. First, few studies have examined the impact of providing similar programs at multiple sites to see if effectiveness is similar in various treatment settings. Second, the role of the duration of treatment has been explored in a limited fashion [34
] without evidence of strong effect of duration of treatment. Oslund et al.
] in an unpublished dissertation compared outcomes for patients with three levels of treatment: 120 h, 72 h, and 24 h. It was found that patients with higher dysfunction pretreatment (i.e.
, greater number of hours resting a day and high levels of pain) profited more with high intensity treatment, whereas persons with lower dysfunction did not respond differentially to levels of intensity of treatment.
In order to further evaluate these issues, the present study utilized a large data set collected over 14 years from two programs with similar models but different locations to address three questions. First, prior to analyzing site and duration, did the program as a whole produce clinically significant change at the completion of treatment across a broad range of outcomes in a large sample of persons with low back pain? Second, were outcomes at the two sites of the program similar or significantly different? Third, did a range of intensity (days of treatment) create differences in outcomes?