Comprehensive assessment of chronic low back pain patients and controls: physical abilities, level of activity, psychological adjustment and pain perception

Non-spinal low back pain: Global epidemiology, trends, and risk factors

Background and Aims

Low back pain (LBP) is one of the most debilitating and prevalent disorders. The prevalence of LBP ranges from 30% to 80%, depending on the population, and increases with age. Causes of LBP are typically classified as spinal and non-spinal. The main goal of this study was to investigate the non-spinal causes of LBP, since neglecting these factors leads to increases in the financial, psychological, and physical burden of LBP on individuals as well as on society.

Methods

The data were extracted after searching the PubMed database and Google Scholar search engine up to October 27, 2021. We included all studies that were conducted on a human population and assessed the effects of epidemiological, biological, psychological, and sociodemographic factors on the incidence or progression of LBP.

Results

The most common causes of non-spinal LBP were diseases such as nephrolithiasis, endometriosis, tumors, fibromyalgia, and conditions like psychological disorders and pregnancy. Nevertheless, the perceived intensity of the pain can be affected by factors such as socioeconomic level, genetics, age, habits, diet, and psychological status.

Conclusion

The epidemiology, etiologies, and risk factors associated with LBP should be more clearly recognized to better prevent, diagnose, and treat the underlying disease and to reduce the burden of LBP.

Do people with low back pain walk differently? A systematic review and meta-analysis

BACKGROUND

The biomechanics of the trunk and lower limbs during walking and running gait are frequently assessed in individuals with low back pain (LBP). Despite substantial research, it is still unclear whether consistent and generalizable changes in walking or running gait occur in association with LBP. The purpose of this systematic review was to identify whether there are differences in biomechanics during walking and running gait in individuals with acute and persistent LBP compared with back-healthy controls.

METHODS

A search was conducted in PubMed, CINAHL, SPORTDiscus, and PsycINFO in June 2019 and was repeated in December 2020. Studies were included if they reported biomechanical characteristics of individuals with and without LBP during steady-state or perturbed walking and running. Biomechanical data included spatiotemporal, kinematic, kinetic, and electromyography variables. The reporting quality and potential for bias of each study was assessed. Data were pooled where possible to compare the standardized mean differences (SMD) between back pain and back-healthy control groups.

RESULTS

Ninety-seven studies were included and reviewed. Two studies investigated acute pain and the rest investigated persistent pain. Nine studies investigated running gait. Of the studies, 20% had high reporting quality/low risk of bias. In comparison with back-healthy controls, individuals with persistent LBP walked slower (SMD = -0.59, 95% confidence interval (95%CI): -0.77 to -0.42)) and with shorter stride length (SMD = -0.38, 95%CI: -0.60 to -0.16). There were no differences in the amplitude of motion in the thoracic or lumbar spine, pelvis, or hips in individuals with LBP. During walking, coordination of motion between the thorax and the lumbar spine/pelvis was significantly more in-phase in the persistent LBP groups (SMD = -0.60, 95%CI: -0.90 to -0.30), and individuals with persistent LBP exhibited greater amplitude of activation in the paraspinal muscles (SMD = 0.52, 95%CI: 0.23-0.80). There were no consistent differences in running biomechanics between groups.

CONCLUSION

There is moderate-to-strong evidence that individuals with persistent LBP demonstrate differences in walking gait compared to back-healthy controls.

Insertion and Presence of Fine-Wire Intramuscular Electrodes to the Lumbar Paraspinal Muscles Do Not Affect Muscle Performance and Activation During High-Exertion Spinal Extension Activities

BACKGROUND

Low back pain (LBP) is commonly associated with paraspinal muscle dysfunctions. A method to study deep lumbar paraspinal (ie, multifidus) muscle function and neuromuscular activation pattern is intramuscular electromyography (EMG). Previous studies have shown that the procedure does not significantly impact muscle function during activities involving low-level muscle contractions. However, it is currently unknown how muscular function and activation are affected during high-exertion contractions.

OBJECTIVE

To examine the effects of insertion and presence of fine-wire EMG electrodes in the lumbar multifidus on muscle strength, endurance, and activation profiles during high-exertion spinal extension muscle contractions.

DESIGN

Single-blinded, repeated measures intervention trial.

SETTING

University clinical research laboratory PARTICIPANTS: Twenty individuals between the ages of 18-40 free of recent and current back pain.

METHODS

Muscle performance was assessed during 3 conditions (with [WI] and without [WO] presence of intramuscular electrodes, and insertion followed by removal [IO]). Isometric spinal extension strength was assessed with a motorized dynamometer. Muscle endurance was assessed using the Sorensen test with neuromuscular activation profiles analyzed during the endurance test.

MAIN OUTCOME MEASUREMENTS

Spinal extensor muscle strength, endurance, and activation.

RESULTS

Our data showed no significant difference in isometric strength (P = .20) between the 3 conditions. A significant difference in muscle endurance was found (P = .03). Post hoc analysis showed that the muscle endurance in the IO condition was significantly higher than the WO condition (161.3 ± 58.3 versus 142.1 ± 48.2 seconds, P = .04), likely due to a learning effect. All 3 conditions elicited minimal pain (range 0-4/10) and comparable muscle activation profiles.

CONCLUSION

Our findings suggested the sonographically guided insertion and presence of fine-wire intramuscular EMG electrodes in the lumbar multifidus muscles had no significant impact on spinal extension muscle function. This study provides evidence that implementing intramuscular EMG does not affect muscle performance during high-exertion contractions in individuals with no current back pain.

LEVEL OF EVIDENCE

II.

Effects of pain intensity on goal schemas and goal pursuit: a daily diary study

OBJECTIVE

Although the adverse effects of chronic pain on work productivity and daily life pursuits are clear, the within-person dynamics of pain, goal cognition, and engagement in work-related and lifestyle goals remain uncharted. This study investigated the impact of pain intensity (assessed on 3 occasions each day) and goal-related schematic thinking (ratings of importance, planning, and goal pursuit opportunities, assessed only in the morning) on afternoon and evening work and lifestyle goal pursuit.

METHODS

A community sample of working adults with chronic pain (N = 131) were screened and interviewed about their work and lifestyle goals and completed a 21-day telephonic diary. Hierarchical linear modeling was used to estimate within-person and between-person effects.

RESULTS

At the within-person level, morning pain intensity was inversely related to schematic cognition concerning work and lifestyle goals, whereas, at the between-person level, morning pain intensity varied positively with schematic thinking about work goals as well with afternoon lifestyle goal pursuit. At both the between- and within- analytic levels, morning goal schemas were positively associated with the pursuit of each type of goal in the afternoon and again in the evening. Moreover, positive carry-over effects of morning goal schemas on next day afternoon goal pursuit were observed.

CONCLUSIONS

Whereas morning pain intensity exhibited inconsistent effects across analytic levels, morning goal-related schematic thinking consistently predicted goal pursuit across analytic levels, type of goal, and time of day. These findings have implications for treatment and prevention of pain's potentially deleterious effects on workplace and lifestyle goals.

Translational nociceptor research as guide to human pain perceptions and pathophysiology

Microneurography is a method for recording single unit action potentials with microelectrodes from the nerves of awake cooperating humans. Although this method is now in use since almost 40 years, its potency has been strengthened by the recent technical developments. A great progress was the discovery that different functional groups of nociceptors are characterized by a distinctly different post-excitatory slowing of their conduction velocities. Microneurography is now powerful enough to analyze the nerve activity pattern of enigmatic sensations such as pruritus. Furthermore, it is the only method providing direct insight in the changes which human nerves undergo with aging. Recently, reliable recordings from patients suffering from painful neuropathies came into reach. It has been shown that different types of neuropathies are characterized by different patterns of abnormal nociceptor functions. Although some of them are characterized by abnormal spontaneous activity in C-nociceptors, others show mainly signs of denervation. Microneurography is, therefore, a tool for translational studies on human nociceptor functions by linking direct animal studies on experimental neuropathies with human diseases.

The disabling role of fluctuations in physical activity in patients with chronic low back pain

Patients with chronic low back pain (CLBP) often report a disabling decrease in their activity level due to pain. The nature of the association between disability, activity, and pain over time is however, unclear. An intriguing issue here is whether a high level of pain-related disability is associated with a low activity level or are changes in the level of activity over time pain provoking and thus more disabling? The objectives of this study were to investigate associations between disability, pain intensity, pain-related fear, and characteristics of physical activity in patients with CLBP. A total of 42 patients with CLBP were recruited from the Pain Clinic of the Maastricht University Hospital. Each pain patient carried an electronic diary for one week, in which questions about current pain intensity, and the level of physical activity were completed at 8 moments a day. Disability was scored by the Quebec Back Pain Disability Scale (QBPDS), Fear of movement by the Tampa Scale for Kinesiophobia (TSK). To explain the level of disability regression analyses were performed with disability as dependent variable and pain intensity, pain-related fear, and consecutively the level of physical activity in daily life and fluctuations in physical activity as independent variables. Results, based on 34 patients, showed that activity fluctuations (beta=0.373, p<0.05) rather than the mean activity level over time (beta=-0.052, ns) contributed significantly in explaining disability. The results are discussed in the light of current theories, previous research, and clinical implications.

Cognitive appraisal and coping in chronic pain patients

OBJECTIVES

This study analyses the relationships between patients' cognitive appraisals concerning their pain and the coping strategies they use. In addition, the way the coping strategy influences the intensity of perceived pain and impairment in these patients was studied.

METHODS

One hundred and twenty two patients with musculoskeletal chronic pain participated. The assessment tools were as follows: The Cognitive Appraisal Inventory for Chronic Pain Patients (CAI), the Vanderbilt Pain Management Inventory (VPMI), the McGill Pain Questionnaire (MPQ) and the Impairment and Functioning Inventory for Chronic Pain Patients (IFI). The hypothetical model was empirically tested using the LISREL 8.20 software package and the unweighted least squares method.

RESULTS

High levels of challenge appraisal were associated with low levels of passive coping and high levels of active coping strategies, whereas the harm, loss or threat appraisal predicted high use of passive coping strategies. Passive coping had three statistically significant path coefficients: high levels of passive coping were associated with low levels of functioning and high levels of pain intensity and impairment. However, high levels of active coping reported high levels of daily functioning.

DISCUSSION

By analysing the cognitive appraisals made by chronic pain patients, clinicians could make better predictions regarding the way they cope and adjust.

Impact of chronic pain on everyday physical activity

Although patients with chronic pain are often considered to have reduced levels of everyday physical activity, data on their activity levels are scarce and inconclusive. Therefore, this study explored whether patients with chronic pain have reduced activity levels, as objectively measured with an activity monitor. The activity monitor is based on long-term ambulatory monitoring of signals from body-fixed accelerometers during everyday life, aimed at assessment of mobility-related activities. Measurements with the monitor were performed during a weekday (24 h) in 18 patients with chronic pain and compared with measurements obtained from 18 gender and age matched healthy comparison subjects. The mean (SD) age of the patients was 44 (11) years, and the mean (SD) duration of their complaints was 8 (7) years. Compared with the healthy subjects, the duration of dynamic activities was not significantly reduced (p=0.10) in the patient group. Mean (SD) intensity of everyday physical activity was lower (p=0.03) in the patients than in the healthy comparison subjects (0.021 [0.006] g versus 0.026 [0.004] g), and patients spent more time lying down (47.0 [10.2]% versus 34.3 [5.6] %; p=0.000) and less time sitting (29.2 [8.9]% versus 36.4 [9.3]%; p=0.03) than the healthy comparison subjects. In spite of significant differences between patients and healthy comparison subjects for some aspects of the activity pattern (which may reflect pain behaviour), the impact of chronic pain on everyday physical activity was relatively small.

An examination of the psychometric structure of the Multidimensional Pain Inventory

Factor analyses to create the Multidimensional Pain Inventory (MPI) warrant further examination due to small sample size, the use of separate factor analyses for each MPI section, and lack of evidence for the replicability of the factor model. The present study randomly assigned 972 respondents to one of three samples. Study 1 used data from Sample 1 (n = 452) to examine the replicability of the MPI factor structure reported by Kerns, Turk, and Rudy (1985), and to measure the internal consistencies of MPI scales. In Study 2, confirmatory factor analyses using Sample 2 data (n = 267) verified a revised MPI factor structure that was generated in Study 1; cross-validation was achieved using data from Sample 3 (n = 253). The revised MPI model differed from the original model in its number of scales and pattern of scale loadings. Recommendations for the refinement of the MPI are proposed.

A comparison of pain, functional limitations, and work status indices as outcome measures in back pain research

STUDY DESIGN

We conducted a prospective study with a 2-year follow-up.

OBJECTIVE

To compare pain, functional limitations, and work status indices as measures of outcome among back pain patients.

SUMMARY OF BACKGROUND DATA

Work status, pain, and functional limitations indices are often considered as interchangeable outcome measures in back pain research. This perspective has been criticized by several authors, who argue that each of these outcome measures reflects a different construct that may vary independently of the others.

METHODS

The study was conducted on 720 patients, who sought care for back pain in primary care settings of a large health maintenance organization in 1989-90, and were interviewed one month and two years later. X2 analyses and receiver operating characteristic curves were used to compare the accuracy of a pain rating and a modified 16-item Roland-Morris score in classifying patients on work status and on the change in work status over time.

RESULTS

Moderate agreement between the pain and functional limitations measures and work status was observed. Pain and functional limitations change scores agreed moderately with improvement in work status, but were poorly associated with decline in work status.

CONCLUSIONS

Although the pain, functional limitations, and work status indices examined in this study are related, they are not equivalent and should not be regarded as interchangeable. These results argue for a clearer distinction of outcome measures in back pain research.

Psychometric properties of the Multidimensional Pain Inventory, Dutch language version (MPI-DLV)

The purpose of this study was to investigate the psychometric properties of a Dutch translation of the Multidimensional Pain Inventory, MPI-DLV. Data was available on 733 chronic pain patients. There were three issues of special interest. The first one related to the comparability between the MPI-DLV and the American and German MPI versions with regard to the psychometric aspects. The second dealt with the construct validity of the MPI-DLV scale 'general activity'. It was predicted that patients with high scores on this scale would be in better physical condition, as measured on a working-to-tolerance bicycle ergometer test. In relation to the third issue, attention was given to the factor-invariance between fibromyalgia patients and back pain patients. From the results obtained it was concluded that (1) the factorial structure of the three MPI parts is replicated and the reliability estimates and validity indicators are similar to those from the American and German versions; (2) patients with high scores on the 'general activity' scale are in better physical condition and (3) MPI-DLVs of fibromyalgia and back pain patients do have similar factorial structures. Evidence was also obtained that the MPI-DLV is sensitive to treatment changes. Applications of the MPI-DLV are discussed.

Assessing depression among persons with chronic pain using the Center for Epidemiological Studies-Depression Scale and the Beck Depression Inventory: a comparative analysis

OBJECTIVE

This study examined the ability of two self-report questionnaires, the Beck Depression Inventory (BDI) and the Center for Epidemiological Studies-Depression Scale (CES-D), to discriminate between chronic pain patients with and without major depression. Since previous research has suggested that medical conditions such as chronic pain can influence the endorsement of items that measure neurovegetative symptoms of depression, the accuracy of each of these questionnaires was also assessed eliminating these items.

SUBJECTS

These included 132 consecutive patients with chronic pain, 44 of whom were diagnosed as suffering from major depression according to DSM-IV criteria.

METHODS

Patients were administered a battery of questionnaires that included the CES-D and BDI. They were also interviewed by a clinical psychologist to determine the presence or absence of major depression.

RESULTS

Both questionnaires were able to discriminate significantly between persons with and without major depression. Removal of the somatic items on each questionnaire did not improve their accuracy. Discriminant function analysis revealed an optimal cut-off score of 21 for the BDI, and 27 for the CES-D. Overall hit rates at these cut-offs for the two questionnaires were comparable, while the CES-D had somewhat better sensitivity (81.8% vs. 68.2%). Conversely, the BDI had slightly better specificity (78.4% vs. 72.7%).

CONCLUSION

The results suggest that both questionnaires have good predictive validity among chronic pain patients, and decisions regarding the use of one questionnaire rather than the other may depend upon the goals of the user and the setting within which the questionnaire is used.

Effective management of chronic pain. The analgesic dilemma

Despite the fact that pain is a common presenting complaint, its effective management remains an elusive goal surrounded by contradictions and controversy. In this article, Dr Stacey discusses the goals of chronic pain management and the treatment options available, with a focus on pharmacologic therapy and prescribing issues involving currently available analgesics.

Psychological factors in disabling low back pain: causes or consequences?

Low back pain (LBP) is a common problem that is costly in both financial and human terms. The impact of LBP on an individual varies greatly. For some, LBP is a minor inconvenience; but for others LBP is associated with significant disability and with psychosocial dysfunction for the individual and for the family. Whether psychosocial factors are causes or consequences has been the subject of debate. This paper is a review of psychosocial factors associated with disabling LBP. It addresses the question of whether these factors are causes or consequences of the disability due to LBP. Based on this review it was concluded that there is little evidence in support of the concept of a pain-prone personality. Once LBP has occurred, the impact of the LBP on the individual and the family is influenced by the health-beliefs and coping strategies of the individual and the family. Distress appears to be secondary to physical restriction rather than pain, but the distress may aggravate the pain and thus the disability. The paper concludes with a discussion of the impact of health practitioners on pain-related disability.

Chronic pain patient-spouse behavioral interactions predict patient disability

Based on behavioral theory, it has been hypothesized that spouse solicitous responses to the pain behaviors of chronic pain patients may contribute to the maintenance of pain behaviors and disability. Self-report data support this hypothesis, but direct observational measures have not been used to study this association. In this study, 50 chronic pain patients and their spouses were videotaped while engaging in common household activities. and patient pain behaviors and spouse solicitous behaviors were coded from the tapes. Spouse solicitous responses to non-verbal pain behaviors were significant predictors of physical disability in the more depressed patients, and were significant predictors of rate of non-verbal pain behavior in patients who reported greater pain. Spouse solicitous responses did not predict psychosocial dysfunction or total self-reported pain behaviors. The result support behavioral theory and indicate the need for further study of the association between spouse solicitousness and patient pain behaviors/disability.

Back pain in the working population: prevalence rates in Dutch trades and professions

An analysis of three health surveys in the Dutch working population is described, aimed at the identification of Dutch trades and professions with relative high and low prevalence rates of back pain. The sample was representative of the working population in the Netherlands and consisted of 5840 men and 2908 women. The analysis included 33 trades and 34 professions, with at least 50 respondents for each. A total of 26.6% of the workers reported back pain quite often. Almost 2% reported absence from work in the last two months, and 4% considered their back pain to be a chronic disabling disease. There was a substantial variation in prevalence rate of low-back pain between trades and professions ranging from 12% to 41%. Trades with relatively high prevalence rates were found to be the building materials industry, the construction industry and road transportation, and the wholesale industry. Trades with relatively low prevalence rates were found to be banking, public administration and commercial services. Workers in the construction industry and supervisory production workers, plumbers, drivers and cleaners have a relatively high prevalence rate of back pain. Chemists, scientists, bookkeepers, secretaries and administrative professions have a relatively low prevalence rate of back pain. It is concluded that high prevalence rates of back pain are found in particular in non-sedentary professions. Priorities in prevention of back pain should be directed towards the group with relatively high prevalence rates identified above.

The frequency of transition of chronic low back pain to fibromyalgia

In a retrospective study, the outcome of the chronic low back pain syndrome was investigated in a group of 53 patients. Average time since the diagnosis was established was 18 years. 25% of the patients--all female but one--developed fibromyalgia. The criteria of Yunus and Wolfe, modified by Müller and Lautenschläger, were applied to establish the diagnosis of fibromyalgia. In 60% of the patients chronic low back pain persisted at the time of final examination, while 8 patients were asymptomatic. Predictive parameters for the chance of getting fibromyalgia were sex and postural disorders such as scoliosis. Other radiological findings, for example degenerative changes of the spine, did not coincide with the group of patients who developed fibromyalgia. The predictive value of pain localisation, number of tender points, presence and severity of functional and vegetative symptoms, and the psychosocial situation is uncertain and should be investigated in further long term prospective studies.

Validity of the Sickness Impact Profile Roland scale as a measure of dysfunction in chronic pain patients

This study examined the reliability and validity of the Roland scale (taken from the Sickness Impact Profile: SIP) as a measure of dysfunction among chronic pain patients. One hundred forty-four subjects completed the SIP when they were screened for admission to an inpatient pain management program. One hundred sixteen subjects were subsequently re-administered the SIP at admission to inpatient treatment. A 3-month post-treatment administration of the SIP was performed for 52 of these subjects. Roland scale scores were calculated from the SIP for each patient. Test-retest stability coefficients indicated that the SIP Roland scale was generally as reliable as the SIP Total, Physical, and Psychosocial scale scores. Consistent with previous research, correlational analyses indicated that the SIP Roland scale is strongly associated with the SIP Physical but not the SIP Psychosocial scale. The SIP Roland scale and the other SIP scales demonstrated similar sensitivity to changes associated with multidisciplinary inpatient treatment for chronic pain. Finally, the pattern of relationships between the SIP Roland scale and several pain-related measures supported the concurrent validity of the SIP Roland scale. The results of the analyses were very similar for patients presenting with and without low back pain. The study supports the reliability and validity of the SIP Roland scale items for assessing dysfunction of chronic pain patients with pain in sites other than the low back as well as those with low back pain.

Multimodal treatment programmes for chronic pain: a quantitative analysis of existing research data

This article reviews the empirical data obtained in existing studies on the multimodal treatment of chronic pain. The majority of these 'treatment packages' are based on a cognitive/behavioural perspective. The articles for review were selected from the scientific literature on this subject which has appeared since the first publication of Fordyce in 1973. The following aspects have been analysed: the goal and structure of the treatment programmes; the method of evaluating treatment results; and the indications for treatment. Programmes for in-patients and out-patients have been compared because it is very likely that there are differences between the treatment methods and study populations. The interval validity and clinical relevance of the available research are discussed in the conclusion.

The Chronic Illness Problem Inventory as a measure of dysfunction in chronic pain patients

Assessment of physical and psychosocial dysfunction is recognized as essential in chronic pain patient evaluation. One instrument, the Sickness Impact Profile (SIP), has demonstrated good reliability and validity as a measure of dysfunction among chronic pain patients. An alternate measure, the Chronic Illness Problem Inventory (CIPI), is shorter and more easily scored than the SIP, but as yet has not been applied widely to chronic pain problems. In the present study, 95 chronic low back pain patients completed the SIP, the CIPI, activity diaries, the McGill Pain Questionnaire (MPQ), and the Center for Epidemiologic Studies-Depression scale (CES-D), before participating in a chronic pain treatment study. Overt pain behaviors were also coded from videotapes of a standardized assessment protocol. Seventy-five subjects completed the measures post-treatment. The results indicate that although the SIP and the CIPI are significantly correlated and appear to be measuring similar constructs, there is also substantial unshared variance between them, suggesting that they may tap somewhat different aspects of dysfunction in chronic pain. The CIPI shows promise as a useful alternative measure of dysfunction in chronic low back pain patients, but requires further validation for this purpose.

A physical approach to the rehabilitation of patients disabled by chronic low back pain

OBJECTIVE

To report the outcome of a multidisciplinary physically based program to treat sufferers of chronic low back pain who had not responded to previous treatment.

DESIGN

Prospective intervention study.

SETTING

The treatment program was conducted at the private practice of Brian C Edwards and Associates Rehabilitation Centre.

PATIENTS

A total of 54 patients participated in the treatment program. All patients were medically referred. No specific exclusion criteria were used; however, all were not working and had not responded to previous treatment.

INTERVENTION

The rehabilitation program consisted of mobilising physiotherapy, isokinetic testing, physical reconditioning, work hardening and psychological testing. This was carried out for seven hours a day, five days a week for four weeks.

RESULTS

Of the 54 patients taking part in this trial 30 (55%) were successfully rehabilitated (returned to work) and remained so at a follow-up session one year later.

CONCLUSION

While selection criteria for successful rehabilitation have not been established, the results do indicate that such physical rehabilitation programs have an important part to play in the rehabilitation of sufferers of chronic low back pain.

Psychological impairments, disabilities, and handicaps: a pilot study of psychological assessment of functioning in chronic pain patients

This study addresses the psychological assessment of functioning in chronic pain patients. First, a model of functional assessment is proposed, which is based on the biopsychosocial view of chronic disease (Engel) and on the consequences of diseases (WHO). Second, a set of psychological criteria for impairments, disabilities, and handicaps, described by WHO as the consequences of diseases, are determined. Third, the psychological criteria selected are operationalized and the utility of the psychological assessment instruments tested in a clinical rehabilitation study. The results indicate that prediction of post-treatment functioning in the rehabilitation patient, by psychological procedures, may improve if the concept of functioning is determined as three sub-areas of impairments, disabilities, and handicaps.

Persistent pain and the injured worker: Integrating biomedical, psychosocial, and behavioral factors in assessment

Health care providers are often asked to determine the level of impairment, degree of disability, and rehabilitation potential for injured workers. Compalints of persistent pain and especially compalaints that are: (1) not substantiated or that are disproportionate to physical pathology identified by physical examination and laboratory diagnostic procedures, or (2) that prove to be differentially responsive to identical treatments that are technically appropriate cause a great deal of frustration for health care providers and third-party payers. Much of the confusion in this area relates to the minimal association between (1) the extent of impairment and degree of disability, and (2) between the magnitude of physical pathology and severity of the pain report. In this paper, we discuss factors that contribute tothe frustration and confusion and propose a comprehensive biobehavioral model that integrates biomedical, psychosocial, and behavioral variables. We also present an assessment model, the Multiaxial Assessment of Pain (MAP) patients, and describe operationalizations of the primary components of this model.

[What do pain scales measure in patients with rheumatoid arthritis?]

In this study carried out in a sample of 80 patients suffering from rheumatoid arthritis (RA) tried an attempt was made to answer the following questions: 1. are there pain factors with a wider range that are more generally applicable than those covered by current German questionnaires? 2. To what extent can somatic parameters predict pain factors? 3. To what extent can a patient's pain behavior (a patient's activity scores) predict pain factors? The study was based on data collected by means of the Pain Experience Questionnaire (PEQ), the McGill Pain Questionnaire MPQ, the West Haven-Yale Multidimensional Pain Inventory WHYMPI, the Measurement Of Patient Outcome Scale MOPO, as well as six different clinical parameters. By means of factor analysis, two second-order factors were extracted, representing 1. the patient's impairment due to intensive pain and 2. socio-emotional consequences of pain. At a statistically significant level, the first factor can be predicted by the clinical variables. Regression of the activity scores on the factor "socio-emotional consequences" suggests a close correlation between the two variables, although the results failed to reach statistical significance. On the whole, the results strongly support the notion of integrating clinical, behavioral and cognitive findings in the diagnostic assessment of chronic rheumatoid pain patients.

Standardized measurement of lateral spinal flexion and its use in evaluation of the effect of treatment of chronic low back pain

To evaluate the effect of treatment of chronic low back pain, the report of subjective pain needs to be supplemented by objective information such as, for example on changes in the functional capacity of the spine. This paper presents a simple but reliable method in this respect i.e. by measuring the range of lateral spinal flexion. When two independent testers used the method the correlation coefficient between their recorded values was 0.98. In patients with chronic low back pain, the method showed that the range of lateral flexion increased after treatment. At linear regression analysis a significant correlation was found between increased range of motion and reduced pain.

Evaluation of low back pain by patient questionnaires and therapist assessment

Paper completed by D.J.B. and J.V.B. in partial fulfillment of the requirements for the Master of Science Degree, Physical Therapy, University of Southern California, Presented at the 63rd Annual Conference, American Physical Therapy Association. June, 1987. The purposes of this study were to determine reliability and validity of history and disability questionnaires completed by 165 low back pain patients; agreement between those questionnaires and a physical therapy assessment was determined. The short term repeatability of the patient-completed questionnaires was 89% and 87%, respectively, while agreement between the two therapists was 75%. Validity of the disability questionnaire was demonstrated. It was not related to epidemiological indicators and had significant agreement with only five out of nine related therapist history items. The patient history questionnaire had an overall agreement of 76% (range 67-93%) with five therapist history items. The pain rating scale was a less reliable index of disability than was the disability score. Physical findings were related to disability statements dealing with flexion and gait. These results suggest the disability questionnaire can be used on North American samples. While use of the three evaluation tools will give a more complete picture of the patient's status, modifications are suggested to increase their usefulness in assessment of patients with low back pain. Further testing is needed to show their utility in prediction of low back pain outcome. J Orthop Sports Phys Ther 1990;11(11):519-529.

Physical findings in patients with chronic intractable benign pain of the neck and/or back

Chronic intractable benign pain (CIBP) is defined as non-neoplastic pain of greater than 6 months duration without objective physical findings and known nociceptive peripheral input. To test the CIBP concept, 283 consecutive chronic pain patients were examined independently by a neurosurgeon and physiatrist and only congruent physical findings were coded. Because they did not fit the CIBP definition, patients with the following primary treatment diagnoses were eliminated: degenerative disease of the spine and spinal stenosis; degenerative disease of the hips; radiculopathy; malignancy; deafferentation pain; and miscellaneous. Eliminated, also, were patients with any one finding indicative of a root compression syndrome, leaving 90 low back and 34 neck patients. These patients had abnormal physical findings in 7 categories: tender points/trigger points; decreased ranges of motion in back or neck; non-anatomical sensory loss; rigid musculature; decreased range of hip motion; gait disturbance; and miscellaneous non-neurologic signs. Low back CIBP patients had the following distribution among the 7 categories: 0% had findings of all 7; 1.1% had 6; 13.3% had 5; 24.4% had 4; 25.6% had 3; 26.7% had 2; 8.9% had 1; and 0% had none. Neck CIBP patients, in which only the first 4 categories of physical findings were applicable had the following distribution: 2.9% had 4; 41.2% had 3; 35.3% had 2; 20.6% had 1; and 0% had none. It was concluded that CIBP patients do have abnormal physical findings indicative of musculoskeletal disease: possibly fibrositis and/or specific myofascial syndromes, as sources of peripheral nociception. These findings question the validity of the CIBP concept and point to the need for a careful, all-inclusive physical examination as a basic initial requirement in the classification of chronic pain patients.

Clinical features of the failed-back syndrome

This study comprises 78 patients who were treated for chronic back pain at a multidisciplinary, multimodal pain treatment center. These patients were selected from 494 patients examined by the authors because all of their previous medical records, operative notes, and imaging studies were available for review. The records and imaging studies were reviewed independently by a neurosurgeon and an orthopedist, and a retrospective decision was made concerning the historical and physical findings correlated with imaging studies in order to provide justification for the intervention. At the time of admission to the pain treatment center, 16 patients had no physical abnormalities that would explain their back complaint and 16 patients exhibited minor postoperative changes insufficient to cause disabling pain. Twenty-seven patients suffered from a complication of previous surgery, 13 had spondylotic disease, and in six a new diagnosis was established. Comprehensive psychiatric evaluation of the 78 patients revealed that 10 patients had a definitive psychiatric diagnosis, 34 were diagnosed as having a maladaptive personality disorder, and 34 had a normal pre-pain personality. Sixty-seven patients suffered from reactive depression. Fifty-four patients were taking medications at doses higher than usually prescribed, 58 misused narcotics, nine had drug addiction, and 54 were suffering withdrawal symptoms. Of the 78 patients, 64 underwent a total of 171 operations, an average of 2.6 per patient. The authors applied the clinical criteria approved by the American Association of Neurological Surgeons and the American Academy of Orthopedic Surgeons for selection of surgery or chemonucleolysis in the treatment of the herniated disc to these patients. Preoperative imaging studies were normal or demonstrated nonspecific degenerative disc disease in 52 patients. Twenty-six patients had a diagnosis based on radiological findings that warranted surgery. Clinical criteria justifying intervention were met in 25 patients and not met in 53. Imaging and clinical criteria for a second operation were met in 18 (40%) of the patients. After the second operation all patients met the criteria: subsequent surgery was necessary to treat effects of an earlier operation in 73%. These data indicate that many of these patients with failed-back syndrome underwent an original operation based on a persistent complaint of pain, frequently coupled with an underlying psychiatric abnormality, although they did not meet the criteria generally accepted by neurosurgeons for intervention at the time of first surgery.

Differential utility of medical procedures in the assessment of chronic pain patients

Physicians are frequently called upon to evaluate patients with chronic pain to (1) establish the etiology, (2) determine the extent of impairment and disability, and (3) prescribe treatment. In many cases, there is little agreement as to what evaluation procedures should be used or how to weight and integrate these findings. Two studies were conducted to determine the domain of procedures pain specialists believe are most important in evaluation and the clinical utility of each. A survey of 75 physicians specializing in the treatment of chronic pain was conducted. Coefficients of concordance indicated that physicians displayed substantial agreement as to the differential utility of 18 physical examination and diagnostic procedures. The relevance of each of these procedures in the assessment of 100 pain patients was evaluated. Differential weights for each procedure derived from the survey were highly correlated with clinical practice. The results of the present studies provide a basis for development of a standardized assessment procedure that incorporates statistically derived weights to quantify medical findings.

Pain assessment methods in mechanical dysfunction

This paper considers the reliability and validity of pain assessment methods in mechanical dysfunction. A distinction is drawn between measures of subjective report and those of pain behaviour. The latter is observable and therefore more amenable to direct study than subjective report. Measures of subjective report include rating scales, the McGill Pain Questionnaire, and diary cards. Consideration is also given to personality assessment in this context. It is concluded that measurement needs to proceed from a number of standpoints, with the importance of each of these dependent upon the context. For chronic pain, emphasis on pain behaviours is appropriate.