Carolina Valencia

A Randomized Trial of Behavioral Physical Therapy Interventions for Acute and Sub-Acute Low Back Pain (NCT00373867)

Abstract Psychological factors consistent with fear‐avoidance models are associated with the development of chronic low back pain (LBP). As a result, graded activity (GA) and graded exposure (GX) have been suggested as behavioral treatment options. This clinical trial compared the effectiveness of treatment‐based classification (TBC) physical therapy alone to TBC augmented with GA or GX for patients with acute and sub‐acute LBP. Our primary hypothesis was that GX would be most effective for those with elevated pain‐related fear. In total, 108 patients enrolled in this clinical trial and were randomly assigned to receive TBC, GA, or GX. Outcomes were assessed by a blinded evaluator at 4 weeks and by mail at 6 months. The primary outcomes for this trial were disability and pain intensity, and the secondary outcomes were fear‐avoidance beliefs, pain catastrophizing, and physical impairment. There were no differences in 4‐week and 6‐month outcomes for reduction of disability, pain intensity, pain catastrophizing, and physical impairment. GX and TBC were associated with larger reductions in fear‐avoidance beliefs at 6 months only. Six‐month reduction in disability was associated with reduction in pain intensity, while 6‐month reduction in pain intensity was associated with reductions in fear‐avoidance beliefs and pain catastrophizing. This trial suggests that supplementing TBC with GA or GX was not effective for improving important outcomes related to the development of chronic LBP.

A Psychometric Investigation of Fear-Avoidance Model Measures in Patients With Chronic Low Back Pain

STUDY DESIGN Validity and test-retest reliability of questionnaires related to the fear-avoidance model (FAM). OBJECTIVE To investigate test-retest reliability, construct redundancy, and criterion validity for 4 commonly used FAM measures. BACKGROUND Few studies have reported psychometric properties for more than 2 FAM measures within the same cohort, making it difficult to determine which specific measures should be implemented in outpatient physical therapy settings. METHODS Fifty-three consecutive patients (mean age, 44.3 + or - 18.5 years) with chronic low back pain participated in this study. Data were collected with validated measures for FAM constructs, including the Fear-Avoidance Beliefs Questionnaire (FABQ), Fear of Pain Questionnaire (FPQ), Tampa Scale for Kinesiophobia, and Pain Catastrophizing Scale. Validated measures were used to investigate criterion validity of the FAM measures, including the Patient Health Questionnaire for depression, the numerical rating scale for pain intensity, the Physical Impairment Scale for physical impairment, and the Oswestry Disability Questionnaire for self-report of disability. Test-retest reliability of the FAM measures was determined with intraclass correlation coefficients (ICC2,1) for total questionnaire scores at baseline and 48 hours later. Construct redundancy was determined with Pearson correlation coefficients for FAM measures. Criterion validity was assessed by 4 separate multiple regression models that included age, sex, and employment status as covariates. Depression, pain intensity, physical impairment, and disability were the dependent variables for these analyses. RESULTS Test-retest ICC coefficients ranged from 0.90 to 0.96 for all FAM questionnaires. The FAM measures were significantly correlated with each other, with the only exception being that the FPQ was not correlated with the FABQ work scale. In the multiple regression models, the Pain Catastrophizing Scale contributed additional variance to depression. The FABQ physical activity scale contributed additional variance to pain intensity and disability. The FABQ work scale contributed additional variance to physical impairment and disability. No other FAM measures contributed to these regression models. CONCLUSION These data suggest that 4 commonly used FAM measures have similar test-retest reliability, with varying amounts of construct redundancy. The criterion validity analyses suggest that measurement of fear-avoidance constructs for patients seeking outpatient physical therapy with chronic low back pain should include the Pain Catastrophizing Scale and the FABQ.

Suprathreshold Heat Pain Response Is Associated With Clinical Pain Intensity for Patients With Shoulder Pain

UNLABELLED Quantitative sensory testing (QST) has become commonly used for the assessment of pain in subjects with clinical conditions. However, there is no consensus about which type of QST is the best predictor of clinical pain responses. The purposes of this study were to determine: a) the QST measure with the strongest association with clinical pain intensity; and b) if the QST measure continued to predict clinical pain intensity in a model including relevant psychological factors. Fifty-nine patients seeking treatment for shoulder pain underwent experimental pain assessment involving heat and pressure stimuli. The patients also completed validated questionnaires for pain intensity, pain catastrophizing, anxiety, and depression. The 5th pain rating in a series of suprathreshold heat pain stimuli accounted for a significant amount of variance in clinical pain intensity, with no other QST measure contributing to the model. The 5th pain rating remained a significant contributor to clinical pain intensity when psychological factors were included in the model. Furthermore, subjects with elevated 5th pain rating, pain catastrophizing, and depression scores had higher clinical pain intensity ratings in pre- and postoperative assessments. These data suggest that assessment of pain should include suprathreshold heat stimuli and psychological factors separately, and a combination of these factors may be predictive of pain intensity outcomes. PERSPECTIVE The current study provides evidence for a suprathreshold heat pain response as a clinically relevant QST measure for patients with shoulder pain, even after psychological factors were considered. The present findings suggest that the 5th pain rating from a series of suprathreshold stimuli, pain catastrophizing, and depression might play a role in predicting pain intensity outcomes.

Experimental Pain Responses Support Peripheral and Central Sensitization in Patients with Unilateral Shoulder Pain

Objective:The aims of this study were to (1) examine the pattern of experimental pain responses in the affected and nonaffected extremities in patients with shoulder pain and (2) explore the intraindividual association between sensitization states derived from experimental pain testing. Methods:Experimental pain responses from 58 patients with shoulder pain (17 women, aged 18 to 52 y) were compared with those from 56 age-matched and sex-matched pain-free volunteers (16 women, aged 21 to 58 y). Experimental pain responses included pressure pain threshold (PPT), thermal pain threshold and tolerance, and suprathreshold heat pain response. Comparisons were made between the affected and nonaffected extremities of clinical participants and the average response of extremities in control participants. Peripheral and central sensitization indexes were computed for clinical participants using standardized scores and percentile cutoffs on the basis of the data from the control sample. Experimental pain responses in clinical participants observed beyond the 25th and 75th percentile of control sample responses were used for investigation of intraindividual association of sensitization states. Results:PPT at the acromion and masseter on the affected side of clinical participants were diminished compared with that on their nonaffected side (P<0.015). Bilateral sensitivity in clinical participants was noted for PPT at the acromion and suprathreshold heat pain response (P<0.015). Peripheral and central sensitization indexes demonstrated that individuals with shoulder pain present with variable patterns of peripheral and central sensitization. Conclusions:Collectively, experimental pain responses supported peripheral and central sensitization in response to pressure and thermal stimuli. No clear association was made between individuals exhibiting peripheral or central sensitization, thus suggesting heterogeneity in pain processing in this clinical population.

Sex differences in experimental and clinical pain sensitivity for patients with shoulder pain

Previous research demonstrates that men and women differ in the way that they perceive and process pain. Much of this work has been done in healthy adults with a lack of consensus in clinical pain populations. The purpose of this study was to investigate how men and women with shoulder pain differ in their experience of experimental and clinical pain and whether psychological processes differentially affect these responses. Fifty‐nine consecutive subjects (24 women, 35 men) seeking operative treatment for shoulder pain were enrolled in this study. Subjects completed self report questionnaires to assess clinical pain, catastrophizing, anxiety and depression and underwent a series of experimental pain tests consisting of pressure pain, thermal pain (threshold and tolerance), and thermal temporal summation. Results indicated that women experienced greater clinical pain and enhanced sensitivity to pressure pain. Age did not affect the observed sex differences. There were no sex differences in psychological association with experimental and clinical pain in this cohort. The relationship between clinical and experimental pressure pain was stronger in women as compared to men. These findings offer insight into the interactions between biological and psychosocial influences of pain and how these interactions vary by sex.Previous research demonstrates that men and women differ in the way that they perceive and process pain. Much of this work has been done in healthy adults with a lack of consensus in clinical pain populations. The purpose of this study was to investigate how men and women with shoulder pain differ in their experience of experimental and clinical pain and whether psychological processes differentially affect these responses. Fifty-nine consecutive subjects (24 women, 35 men) seeking operative treatment for shoulder pain were enrolled in this study. Subjects completed self report questionnaires to assess clinical pain, catastrophizing, anxiety and depression and underwent a series of experimental pain tests consisting of pressure pain, thermal pain (threshold and tolerance), and thermal temporal summation. Results indicated that women experienced greater clinical pain and enhanced sensitivity to pressure pain. Age did not affect the observed sex differences. There were no sex differences in psychological association with experimental and clinical pain in this cohort. The relationship between clinical and experimental pressure pain was stronger in women as compared to men. These findings offer insight into the interactions between biological and psychosocial influences of pain and how these interactions vary by sex.

Clinical Investigation of Pain-related Fear and Pain Catastrophizing for Patients With Low Back Pain

ObjectiveTo investigate select psychometric properties of fear-avoidance model measures commonly used to assess pain-related fear and catastrophizing in clinical studies of low back pain. MethodsA convenience sample was recruited from patients (n=80) seeking outpatient physical therapy for low back pain. All patients completed self-report questionnaires for pain-related fear [Fear-avoidance Beliefs Questionnaire-physical activity (FABQ-PA), FABQ-work scale (W), and Tampa Scale for Kinesiophobia -11] and pain catastrophizing (PCS) at initial evaluation session. Patients also completed clinical measures for pain intensity (numerical rating scale) and self-report of disability (Oswestry Disability Index) at the initial evaluation session. Construct redundancy of the fear-avoidance questionnaires was assessed by factor analysis for individual items and Pearson correlation for total questionnaire scores. Concurrent validity was investigated with multiple regression models for pain intensity and disability. ResultsItem analysis indicated all PCS and FABQ-W items loaded on 2 separate factors. The FABQ-PA and Tampa Scale for Kinesiophobia-11 loaded together on a third factor. As expected, all of the fear-avoidance questionnaires were significantly correlated with each other to varying degrees (rs ranged from 0.28 to 0.55, P<0.05 for all). In the multiple regression models only the FABQ-PA and PCS contributed unique variance to pain intensity and disability measures. Further analysis indicated the PCS mediated the relationship of the FABQ-PA by weakening its association with pain intensity and disability. DiscussionThese analyses suggest clinical assessment of the Fear-Avoidance Model of Musculoskeletal Pain likely captures 3 factors including PCS, beliefs about work, and beliefs about physical activity. The FABQ-PA and PCS can be recommended for clinical use because of their unique associations with pain intensity and disability. The FABQ-W may only be appropriate for those interested in assessing work specific beliefs.

Depressive Symptoms, Anatomical Region, and Clinical Outcomes for Patients Seeking Outpatient Physical Therapy for Musculoskeletal Pain

Background Clinical guidelines advocate the routine identification of depressive symptoms for patients with pain in the lumbar or cervical spine, but not for other anatomical regions. Objective The purpose of this study was to investigate the prevalence and impact of depressive symptoms for patients with musculoskeletal pain across different anatomical regions. Design This was a prospective, associational study. Methods Demographic, clinical, depressive symptom (Symptom Checklist 90–Revised), and outcome data were collected by self-report from a convenience sample of 8,304 patients. Frequency of severe depressive symptoms was assessed by chi-square analysis for demographic and clinical variables. An analysis of variance examined the influence of depressive symptoms and anatomical region on intake pain intensity and functional status. Separate hierarchical multiple regression models by anatomical region examined the influence of depressive symptoms on clinical outcomes. Results Prevalence of severe depression was higher in women, in industrial and pain clinics, and in patients who reported chronic pain or prior surgery. Lower prevalence rates were found in patients older than 65 years and those who had upper- or lower-extremity pain. Depressive symptoms had a moderate to large effect on pain ratings (Cohen d=0.55–0.87) and a small to large effect on functional status (Cohen d=0.28–0.95). In multivariate analysis, depressive symptoms contributed additional variance to pain intensity and functional status for all anatomical locations, except for discharge values for the cervical region. Conclusions Rates of depressive symptoms varied slightly based on anatomical region of musculoskeletal pain. Depressive symptoms had a consistent detrimental influence on outcomes, except on discharge scores for the cervical anatomical region. Expanding screening recommendations for depressive symptoms to include more anatomical regions may be indicated in physical therapy settings.

Investigation of Central Pain Processing in Shoulder Pain: Converging Results From 2 Musculoskeletal Pain Models

UNLABELLED Recent reports suggest deficits in conditioned pain modulation (CPM) and enhanced suprathreshold heat pain response (SHPR) potentially play a role in the development of chronic pain. The purpose of this study was to investigate whether central pain processing was altered in 2 musculoskeletal shoulder pain models. The goals of this study were to determine whether central pain processing: 1) differs between healthy subjects and patients with clinical shoulder pain; 2) changes with induction of exercise-induced muscle pain; and 3) changes 3 months after shoulder surgery. Fifty-eight patients with clinical shoulder pain and 56 age- and sex-matched healthy subjects were included in these analyses. The healthy cohort was examined before inducing EIMP, and 48 and 96 hours later. The clinical cohort was examined before shoulder surgery and 3 months later. CPM did not differ between the cohorts, however; SHPR was elevated for patients with shoulder pain compared to healthy controls. Induction of acute shoulder pain with EIMP resulted in increased shoulder pain intensity but did not change CPM or SHPR. Three months following shoulder surgery, clinical pain intensity decreased but CPM was unchanged from preoperative assessment. In contrast, SHPR was decreased and showed values comparable with healthy controls at 3 months. Therefore, the present study suggests that: 1) clinical shoulder pain is associated with measurable changes in central pain processing; 2) exercise-induced shoulder pain did not affect measures of central pain processing; and 3) elevated SHPR was normalized with shoulder surgery. Collectively our findings support neuroplastic changes in pain modulation were associated with decreases in clinical pain intensity only, and could be detected more readily with thermal stimuli. PERSPECTIVE Longitudinal studies involving quantitative sensory testing are rare. In exploring 2 musculoskeletal shoulder pain models (exercise-induced muscle pain and surgical pain), conditioned pain modulation was unchanged from pre- to post-assessment in both models. Suprathreshold heat pain response decreased after shoulder surgery and was comparable to healthy controls, suggesting this measure may be sensitive to decreases in clinical pain intensity.

Development of a Self-Report Measure of Fearful Activities for Patients With Low Back Pain: The Fear of Daily Activities Questionnaire

Background: Self-report measures for assessing specific fear of activities have not been reported in the peer-reviewed literature, but are necessary to adequately test treatment hypotheses related to fear-avoidance models. Objective: This study described psychomotor properties of a novel self-report measure, the Fear of Daily Activities Questionnaire (FDAQ). Design: A prospective cohort design was used. Methods: Reliability and validity cohorts were recruited from outpatient physical therapy clinics. Analyses for the reliability cohort included internal consistency and 48-hour test-retest coefficients, as well as standard error of measurement and minimal detectable change estimates. Analyses for the validity cohort included factor analysis for construct validity and correlation and multiple regression analyses for concurrent and predictive validity. Four-week responsiveness was assessed by paired t test, effect size calculation, and percentage of patients meeting or achieving MDC criterion. Results: The FDAQ demonstrated adequate internal consistency (Cronbach alpha=.91, 95% confidence interval=.87–.95) and 48-hour test-retest properties (intraclass correlation coefficient=.90, 95% confidence interval=.82–.94). The standard error of measurement for the FDAQ was 6.6, resulting in a minimal detectable change of 12.9. Factor analysis suggested a 2- or 3-factor solution consisting of loaded spine, postural, and spinal movement factors. The FDAQ demonstrated concurrent validity by contributing variance to disability (baseline and 4 weeks) and physical impairment (baseline) scores. In predictive validity analyses, baseline FDAQ scores did not contribute variance to 4-week disability and physical impairment scores, but changes in FDAQ scores were associated with changes in disability. The FDAQ scores significantly decreased over a 4-week treatment period, with an effect size of .86 and 55% of participants meeting the minimal detectable change criterion. Limitations: The validity cohort was a secondary analysis of a clinical trial, and additional research is needed to confirm these findings in other samples. Conclusions: The FDAQ is a potentially viable measure for fear of specific activities in physical therapy settings. These analyses suggest the FDAQ may be appropriate for determining graded exposure treatment plans and monitoring changes in fear levels, but is not appropriate as a screening tool.

Investigation of central pain processing in postoperative shoulder pain and disability.

Background:Measures of central pain processing like conditioned pain modulation and suprathreshold heat pain response (SHPR) have been described to assess different components of central pain modulatory mechanisms. Central pain processing potentially plays a role in the development of postsurgical pain, however, the role of conditioned pain modulation and SHPR in explaining postoperative clinical pain and disability is still unclear. Methods:Seventy-eight patients with clinical shoulder pain were included in this study. Patients were examined before shoulder surgery, at 3 months, and 6 months after surgery. The primary outcome measures were pain intensity and upper extremity disability. Results:Analyses revealed that the change score (baseline- 3 mo) of fifth pain rating of SHPR accounted for a significant amount of variance in 6-month postsurgical clinical pain intensity and disability after age, sex, preoperative pain intensity, and relevant psychological factors were considered. Conclusions:The present study suggests that baseline measures of central pain processing were not predictive of 6-month postoperative pain outcome. Instead, the 3-month change in SHPR might be a relevant factor in the transition to an elevated 6-month postoperative pain and disability outcomes. In patients with shoulder pain, the 3-month change in a measure of central pain processing might be a relevant factor in the transition to elevated 6-month postoperative pain and disability scores.