Jason M. Beneciuk

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.

Clinical Prediction Rules for Physical Therapy Interventions: A Systematic Review

Background and Purpose: Clinical prediction rules (CPRs) involving physical therapy interventions have been published recently. The quality of the studies used to develop the CPRs was not previously considered, a fact that has potential implications for clinical applications and future research. The purpose of this systematic review was to determine the quality of published CPRs developed for physical therapy interventions. Methods: Relevant databases were searched up to June 2008. Studies were included in this review if the explicit purpose was to develop a CPR for conditions commonly treated by physical therapists. Validated CPRs were excluded from this review. Study quality was independently determined by 3 reviewers using standard 18-item criteria for assessing the methodological quality of prognostic studies. Percentage of agreement was calculated for each criterion, and the intraclass correlation coefficient (ICC) was determined for overall quality scores. Results: Ten studies met the inclusion criteria and were included in this review. Percentage of agreement for individual criteria ranged from 90% to 100%, and the ICC for the overall quality score was .73 (95% confidence interval=.27–.92). Criteria commonly not met were adequate description of inclusion or exclusion criteria, inclusion of an inception cohort, adequate follow-up, masked assessments, sufficient sample sizes, and assessments of potential psychosocial factors. Quality scores for individual studies ranged from 48.2% to 74.0%. Discussion and Conclusion: Validation studies are rarely reported in the literature; therefore, CPRs derived from high-quality studies may have the best potential for use in clinical settings. Investigators planning future studies of physical therapy CPRs should consider including inception cohorts, using longer follow-up times, performing masked assessments, recruiting larger sample sizes, and incorporating psychological and psychosocial assessments.

Immediate reduction in temporal sensory summation after thoracic spinal manipulation

BACKGROUND CONTEXT Spinal manipulative techniques (SMT) have shown clinical effectiveness in some patients with musculoskeletal pain. PURPOSE We performed the current experiment to test whether regional pain modulation is to be expected from thoracic SMT. STUDY DESIGN/SETTING Randomized experimental design performed in a university pain laboratory. OUTCOME MEASURES The primary outcome was experimental pain sensitivity in cervical and lumbar innervated area. METHODS Ninety healthy volunteers were randomly assigned to receive one of three interventions (SMT, exercise, or rest) to the upper thoracic spine. Participants completed questionnaires about pain-related affect and expectations regarding each of the interventions. We collected experimental pain sensitivity measures of cervical and lumbar innervated areas before and immediately after randomly assigned intervention. Mixed model analysis of covariance was used to test changes in measures of experimental pain sensitivity. RESULTS No interactions or intervention (group) effects were noted for pressure or A-delta-mediated thermal pain responses. Participants receiving SMT had greater reductions in temporal sensory summation (TSS). CONCLUSIONS This present study indicates thoracic SMT that reduces TSS in healthy subjects. These findings extend our previous work in healthy and clinical subjects by indicating change in the nocioceptive afferent system occurred caudal to the region of SMT application. However, the duration of reduction in TSS is unknown, and more work needs to be completed in clinical populations to confirm the relevance of these findings.

Effects of Upper Extremity Neural Mobilization on Thermal Pain Sensitivity: A Sham-Controlled Study in Asymptomatic Participants

STUDY DESIGN A single-blinded, quasi-experimental, within- and between-sessions assessment. OBJECTIVES To investigate potential mechanisms of neural mobilization (NM), using tensioning techniques in comparison to sham NM on a group of asymptomatic volunteers between the ages of 18 and 50. BACKGROUND NM utilizing tensioning techniques is used by physical therapists in the treatment of patients with cervical and/or upper extremity symptoms. The underlying mechanisms of potential benefits associated with NM tensioning techniques are unknown. METHODS AND MEASURES Participants (n = 62) received either a NM or sham NM intervention 2 to 3 times a week for a total of 9 sessions, followed by a 1-week period of no intervention to assess carryover effects. A-delta (first pain response) and C-fiber (temporal summation) mediated pain perceptions were tested via thermal quantitative sensory testing procedures. Elbow extension range of motion (ROM) and sensory descriptor ratings were obtained during a neurodynamic test for the median nerve. Data were analyzed with repeated-measures analysis of variance (ANOVA). RESULTS No group differences were seen for A-delta mediated pain perception at either immediate or carryover times. Group differences were identified for immediate C-fiber mediated pain perception (P = .032), in which hypoalgesia occurred for the NM group but not the sham NM group. This hypoalgesic effect was not maintained at carryover (P = .104). Group differences were also identified for the 3-week and carryover periods for elbow extension ROM (P = .004), and for the participant sensory descriptor ratings (P = .018), in which increased ROM and decreased sensory descriptor ratings were identified in participants in the NM group but not the sham NM group. CONCLUSION This study provides preliminary evidence that mechanistic effects of tensioning NM differ from sham NM for asymptomatic participants. Specifically, NM resulted in immediate, but not sustained, C-fiber mediated hypoalgesia. Also, NM was associated with increased elbow ROM and a reduction in sensory descriptor ratings at 3-week and carryover assessment times. These differences provide potentially important information on the mechanistic effects of NM, as well as the description of a sham NM for use in future clinical trials.

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.

Low Back Pain Subgroups using Fear-Avoidance Model Measures: Results of a Cluster Analysis

Objectives:The purpose of this secondary analysis was to test the hypothesis that an empirically derived psychological subgrouping scheme based on multiple Fear-Avoidance Model (FAM) constructs would provide additional capabilities for clinical outcomes in comparison with a single FAM construct. Methods:Patients (n=108) with acute or subacute low back pain enrolled in a clinical trial comparing behavioral physical therapy interventions to classification-based physical therapy completed baseline questionnaires for Pain Catastrophizing Scale, fear-avoidance beliefs [Fear-Avoidance Beliefs Questionnaire (FABQ)-physical activity scale (PA), FABQ work scale], and patient-specific fear (Fear of Daily Activities Questionnaire). Clinical outcomes included pain intensity and disability measured at baseline, 4 weeks, and 6 months. A hierarchical agglomerative cluster analysis was used to create distinct cluster profiles among the FAM measures and discriminant analysis was used to interpret clusters. Changes in clinical outcomes were investigated with repeated measures analysis of variance and differences in results based on cluster membership were compared with FABQ-PA subgrouping used in the original trial. Results:Three distinct FAM subgroups (Low-Risk, High Specific Fear, and High Fear and Catastrophizing) emerged from cluster analysis. Subgroups differed on baseline pain and disability (P<0.01) with the High Fear and Catastrophizing subgroup associated with greater pain than the Low-Risk subgroup (P<0.01) and the greatest disability (P<0.05). Subgroup×time interactions were detected for both pain and disability (P<0.05) with the High Fear and Catastrophizing subgroup reporting greater changes in pain and disability than other subgroups (P<0.05). In contrast, FABQ-PA subgroups used in the original trial were not associated with interactions for clinical outcomes. Discussion:These data suggest that subgrouping based on multiple FAM measures may provide additional information on clinical outcomes in comparison with determining subgroup status by FABQ-PA alone. Subgrouping methods for patients with low back pain should include multiple psychological factors to further explore if patients can be matched with appropriate interventions.

Pain catastrophizing predicts pain intensity during a neurodynamic test for the median nerve in healthy participants

Psychological factors within the Fear-Avoidance Model of Musculoskeletal Pain (FAM) predict clinical and experimental pain in both symptomatic and asymptomatic individuals. Clinicians routinely examine individuals with provocative testing procedures that evoke symptoms. The purpose of this study was to investigate which FAM factors were associated with evoked pain intensity, non-painful symptom intensity, and range of motion during an upper-limb neurodynamic test. Healthy participants (n = 62) completed psychological questionnaires for pain catastrophizing, fear of pain, kinesiophobia, and anxiety prior to neurodynamic testing. Pain intensity, non-painful sensation intensity, and elbow range of motion (ROM) were collected during testing and served as dependent variables in separate simultaneous regression models. All the psychological predictors in the model accounted for 18% of the variance in evoked pain intensity (p = .02), with only pain catastrophizing (beta = .442, p < .01) contributing uniquely to the model. Psychological predictors did not explain significant amounts of variance for the non-painful sensation intensity and ROM models. These findings suggest that pain catastrophizing contributed specifically to evoked pain intensity ratings during neurodynamic testing for healthy subjects. Although these findings cannot be directly translated to clinical practice, the influence of pain catastrophizing on evoked pain responses should be considered during neurodynamic testing.

Pragmatic Implementation of a Stratified Primary Care Model for Low Back Pain Management in Outpatient Physical Therapy Settings: Two-Phase, Sequential Preliminary Study

Background The effectiveness of risk stratification for low back pain (LBP) management has not been demonstrated in outpatient physical therapy settings. Objective The purposes of this study were: (1) to assess implementation of a stratified care approach for LBP management by evaluating short-term treatment effects and (2) to determine feasibility of conducting a larger-scale study. Design This was a 2-phase, preliminary study. Methods In phase 1, clinicians were randomly assigned to receive standard (n=6) or stratified care (n=6) training. Stratified care training included 8 hours of content focusing on psychologically informed practice. Changes in LBP attitudes and beliefs were assessed using the Pain Attitudes and Beliefs Scale for Physiotherapists (PABS-PT) and the Health Care Providers Pain and Impairment Relationship Scale (HC-PAIRS). In phase 2, clinicians receiving the stratified care training were instructed to incorporate those strategies in their practice and 4-week patient outcomes were collected using a numerical pain rating scale (NPRS), and the Oswestry Disability Index (ODI). Study feasibility was assessed to identify potential barriers for completion of a larger-scale study. Results In phase 1, minimal changes were observed for PABS-PT and HC-PAIRS scores for standard care clinicians (Cohen d=0.00–0.28). Decreased biomedical (−4.5±2.5 points, d=1.08) and increased biopsychosocial (+5.5±2.0 points, d=2.86) treatment orientations were observed for stratified care clinicians, with these changes sustained 6 months later on the PABS-PT. In phase 2, patients receiving stratified care (n=67) had greater between-group improvements in NPRS (0.8 points; 95% confidence interval=0.1, 1.5; d=0.40) and ODI (8.9% points; 95% confidence interval=4.1, 13.6; d=0.76) scores compared with patients receiving standard physical therapy care (n=33). Limitations In phase 2, treatment was not randomly assigned, and therapist adherence to treatment recommendations was not monitored. This study was not adequately powered to conduct subgroup analyses. Conclusions In physical therapy settings, biomedical orientation can be modified, and risk-stratified care for LBP can be effectively implemented. Findings from this study can be used for planning of larger studies.

What effect can manual therapy have on a patient's pain experience?

Manual therapy (MT) is a passive, skilled movement applied by clinicians that directly or indirectly targets a variety of anatomical structures or systems, which is utilized with the intent to create beneficial changes in some aspect of the patient pain experience. Collectively, the process of MT is grounded on clinical reasoning to enhance patient management for musculoskeletal pain by influencing factors from a multidimensional perspective that have potential to positively impact clinical outcomes. The influence of biomechanical, neurophysiological, psychological and nonspecific patient factors as treatment mediators and/or moderators provides additional information related to the process and potential mechanisms by which MT may be effective. As healthcare delivery advances toward personalized approaches there is a crucial need to advance our understanding of the underlying mechanisms associated with MT effectiveness.