A Standardized Assessment of Movement-evoked Pain Ratings Is Associated With Functional Outcomes in Older Adults With Chronic Low Back Pain

Association of Muscle Strength, Psychological Factors, and Central Sensitization With Movement-Evoked Pain in Patients With Nonspecific Chronic Low Back Pain: The BACKFIT Project

BACKGROUND

People with chronic pain might evade certain movements to prevent their experience of pain. Movement-evoked pain (MEP) might induce lower functionality during daily activities.

HYPOTHESIS

(1) MEP after physical fitness tests would vary depending on the main musculature involved in the test; (2) physical and psychological factors would be associated with MEP in patients with NSCLBP.

STUDY DESIGN

Cross-sectional design.

LEVEL OF EVIDENCE

Level 3.

METHODS

A total of 104 (69 women) patients aged 51.0 ± 10.3 years with NSCLBP participated. MEP was measured with a visual analog scale (VAS) at baseline and immediately after performing each physical fitness test, that is, the Biering-Sørensen, prone bridging, handgrip, chair-stand, and 8-foot time-up-and-go tests, measuring back extensor, back flexor, upper- and lower-body muscle strength, and motor agility, respectively. Global muscle strength was calculated with normalized index (z-score) procedure. Depression, anxiety, pain catastrophizing, and central sensitization were assessed with the Beck Depression Inventory II, State Trait Anxiety Inventory I, Pain Catastrophizing Scale, and Central Sensitization Inventory (CSI), respectively.

RESULTS

Patients showed greater pain after completion of the Biering-Sørensen (mean difference 95% CI, 0.02, 1.11), prone bridging (0.15, 1.21), lower pain after handgrip (-1.46, -0.52), and the 8-foot time-up-and-go (-1.43, 0.46) tests (all P ≤ 0.04). Lower global muscular strength (β between -0.18 and -0.30), and greater pain catastrophizing (β = 0.16), and CSI scoring (β between 0.18 and 0.27) were associated with greater MEP (all P ≤ 0.04).

CONCLUSION

Greater MEP was observed after tests measuring core musculature strength than after tests measuring distal (limbs) strength and agility. Greater MEP was overall associated with lower muscle strength, greater pain catastrophizing, and central sensitization.

CLINICAL RELEVANCE

Fitness testing might be implemented as a complementary tool for the monitoring of NSCLBP in clinical settings.

Minimal Clinically Important Change of Movement Pain in Musculoskeletal Pain Conditions

Movement pain, which is distinct from resting pain, is frequently reported by individuals with musculoskeletal pain. There is growing interest in measuring movement pain as a primary outcome in clinical trials, but no minimally clinically important change (MCIC) has been established, limiting interpretations. We analyzed data from 315 participants who participated in previous clinical trials (65 with chronic Achilles tendinopathy; 250 with fibromyalgia) to establish an MCIC for movement pain. A composite movement pain score was defined as the average pain (Numeric Rating Scale: 0-10) during 2 clinically relevant activities. The change in movement pain was calculated as the change in movement pain from pre-intervention to post-intervention. A Global Scale (GS: 1-7) was completed after the intervention on perceived change in health status. Participants were dichotomized into non-responders (GS ≥4) and responders (GS <3). Receiver operating characteristic curves were calculated to determine threshold values and corresponding sensitivity and specificity. We used the Euclidean method to determine the optimal threshold point of the Receiver operating characteristic curve to determine the MCIC. The MCIC for raw change in movement pain was 1.1 (95% confidence interval [CI]: .9-1.6) with a sensitivity of .83 (95% CI: .75-.92) and specificity of .79 (95% CI: .72-.86). For percent change in movement pain the MCIC was 27% (95% CI: 10-44%) with a sensitivity of .79 (95% CI: .70-.88) and a specificity of .82 (95% CI: .72-.90). Establishing an MCIC for movement pain will improve interpretations in clinical practice and research. PERSPECTIVE: A minimal clinically important change (MCIC) of 1.1- points (95% CI: .9-1.6) for movement pain discriminates between responders and non-responders to rehabilitation. This MCIC provides context for interpreting the meaningfulness of improvement in pain specific to movement tasks.

Through the Lens of Movement-Evoked Pain: A Theoretical Framework of the "Pain-Movement Interface" to Guide Research and Clinical Care for Musculoskeletal Pain Conditions

Over 120 million Americans report experiencing pain in the past 3 months. Among these individuals, 50 million report chronic pain and 17 million report pain that limits daily life or work activities on most days (ie, high-impact chronic pain). Musculoskeletal pain conditions in particular are a major contributor to global disability, health care costs, and poor quality of life. Movement-evoked pain (MEP) is an important and distinct component of the musculoskeletal pain experience and represents an emerging area of study in pain and rehabilitation fields. This focus article proposes the "Pain-Movement Interface" as a theoretical framework of MEP that highlights the interface between MEP, pain interference, and activity engagement. The goal of the framework is to expand knowledge about MEP by guiding scientific inquiry into MEP-specific pathways to disability, high-risk clinical phenotypes, and underlying individual influences that may serve as treatment targets. This framework reinforces the dynamic nature of MEP within the context of activity engagement, participation in life and social roles, and the broader pain experience. Recommendations for MEP evaluation, encompassing the spectrum from high standardization to high patient specificity, and MEP-targeted treatments are provided. Overall, the proposed framework and recommendations reflect the current state of science in this emerging area of study and are intended to support future efforts to optimize musculoskeletal pain management and enhance patient outcomes. PERSPECTIVE: Movement-evoked pain (MEP) is a distinct component of the musculoskeletal pain experience and emerging research area. This article introduces the "Pain-Movement Interface" as a theoretical framework of MEP, highlighting the interface between MEP, pain interference, and activity engagement. Evaluating and treating MEP could improve rehabilitation approaches and enhance patient outcomes.

Changes in spinal motor behaviour are associated with reduction in disability in chronic low back pain: A longitudinal cohort study with 1-year follow-up

BACKGROUND

The need to improve spinal motor behaviour in chronic low back pain (CLBP) rehabilitation remains unclear. The objective of this study was to test if changes in spinal motor behaviour were associated with changes in disability after an interdisciplinary rehabilitation program (IRP) in patients with CLBP.

METHODS

Seventy-one patients with CLBP participating in an IRP were included. Spinal motor behaviour was assessed with biomechanical (lumbar angular amplitude and velocity, erector spinae muscle activity and duration of the task), cognitive-emotional (task-specific fear [PRF]) and pain-related (movement-evoked pain [MEP]) measures during a lifting task before and after the IRP. Disability was measured before and after the IRP, and at 3-month and 1-year follow-ups.

RESULTS

After adjusting for confounders, changes in disability were significantly associated with MEP changes (β adj. = 0.49, p < 0.001) and PRF changes (β adj. = 0.36, p = 0.008), but not with changes in any of the biomechanical measures. MEP at the end of IRP was also associated with disability at 3 months (β adj. = 0.37, p = 0.001) and 1 year (β adj. = 0.42, p = 0.01). Biomechanical measures at the end of the IRP were not associated with disability, except for the duration of the task that was significantly associated with reduction of disability at 3 months (β non-adj = 0.5, p < 0.001).

CONCLUSIONS

Pain-related and cognitive-emotional measures of spinal motor behaviour were associated with reduction in disability following an IRP. Future research is needed to further investigate causal relationships between spinal motor behaviour and disability.

SIGNIFICANCE STATEMENT

This study supports a multidimensional understanding and analysis of spinal motor behaviour, integrating the cognitive-emotional, pain-related and biomechanical domains. It also supports the consideration of spinal motor behaviour as a potentially important treatment target in chronic low back pain management. Moreover, it suggests that reducing movement-evoked pain and task-specific fear may have more influence on disability than changing lumbar amplitude, lumbar angular velocity or erector muscle activity, which may have important implications for rehabilitation.

Hip-focused physical therapy versus spine-focused physical therapy for older adults with chronic low back pain at risk for mobility decline (MASH): a multicentre, single-masked, randomised controlled trial

BACKGROUND

Previously, we identified a population of older adults with chronic low back pain, hip pain, and hip muscle weakness who had worse 12-month low back pain and functional outcomes than age-matched adults with only low back pain, indicating an increased risk for future mobility decline. We sought to determine whether tailored, hip-focused physical therapy reduced pain and functional limitations in this high-risk population compared with non-tailored, spine-focused physical therapy.

METHODS

We did a multicentre, single-masked, randomised controlled trial at three research-based sites in the USA. We recruited older adults (aged 60-85 years) with hip pain and weakness who reported moderate low back pain intensity at least half the days in the last 6 months. Patients were randomly assigned to hip-focused physical therapy or spine-focused physical therapy using permuted blocks with random block size, stratified by site and sex (ie, male or female). The primary outcomes were self-reported disability using the Quebec Back Pain Disability Scale (QBPDS) and performance-based 10-Meter Walk Test (10MWT) at 8 weeks. All analyses were done in the intention-to-treat population. Adverse events were collected by study staff via a possible adverse event reporting form and then adjudicated by site investigators. This trial was registered with ClinicalTrials.gov, NCT04009837.

FINDINGS

Between Nov 1, 2019, and April 30, 2022, 184 participants were randomly assigned to receive hip-focused (n=91) or spine-focused physical therapy (n=93) interventions. The mean age was 70·7 (SD 6·2) years. 121 (66%) of 184 participants were women, 63 (34%) were men, and 149 (81%) were White. At 8 weeks, the mean between-group difference on the QBPDS was 4·0 (95% CI 0·5 to 7·5), favouring hip-focused physical therapy. Both groups had similar, clinically meaningful gait speed improvements (10MWT) at 8 weeks (mean difference 0·004 m/s [95% CI -0·044 to 0·052]). No serious adverse events were related to study participation.

INTERPRETATION

Tailored hip-focused physical therapy demonstrated greater improvements in low back pain-related disability at 8 weeks. However, both hip-focused physical therapy and spine-focused physical therapy produced clinically meaningful improvements in disability and function for this high-risk population at 6 months. These findings warrant further investigation before clinical implementation.

FUNDING

US National Institute on Aging of the National Institutes of Health.

Personal factors and baseline function in patients undergoing non-operative management for chronic hip-related groin pain: a cross-sectional study

Aim

Little is known about the relationship between personal factors and perception of hip-related function among patients with chronic hip-related groin pain (HRGP) seeking non-operative management. This analysis was performed to determine if depressive symptoms, central sensitisation, movement evoked pain (MEP), pressure hypersensitivity and activity level were associated with patients' perception of hip-related function, represented by the International Hip Outcome Tool (iHOT-33).

Methods

This cross-sectional study used baseline data from a pilot randomised clinical trial. Participants had anterior hip symptoms for at least 3 of the past 12 months reproduced on examination. Depressive symptoms, central sensitisation and activity level were quantified with self-report questionnaires. MEP was assessed during step down and squat. Pain pressure threshold (PPT) was used to assess pressure hypersensitivity. Statistical analysis was performed to assess bivariate association between variables and independent association of variables with iHOT-33.

Results

Data from 33 participants (aged 18-40 years) with HRGP were analysed. Greater depressive symptoms (rs=-0.48, p=0.005), higher MEP during step down (rs=-0.36, p=0.040) and squat (rs=-0.39, p=0.024), and greater central sensitisation (rs=-0.33, p=0.058) were associated with lower (worse) iHOT-33 scores. Greater depressive symptoms (β=-0.47, 95% CI -0.76 to -0.17; p=0.003) and higher MEP during squat (β=-0.38, 95% CI -0.68 to -0.08; p=0.014) accounted for 37% of variability in iHOT-33. After adjusting for depressive symptoms and MEP, PPT, central sensitisation symptoms and activity level were not associated iHOT-33.

Conclusions

In patients with HRGP seeking non-operative management, greater depressive symptoms and MEP are independently associated with worse self-perceived hip function.

Trial registration number

NCT03959319.

Construct validity of movement-evoked pain operational definitions in older adults with chronic low back pain

OBJECTIVE

Movement-evoked pain (MeP) may predispose the geriatric chronic low back pain (LBP) population to health decline. As there are differing operational definitions for MeP, the question remains as to whether these different definitions have similar associations with health outcomes in older adults with chronic LBP.

DESIGN

Cross-sectional analysis of an observational study.

SETTING

Clinical research laboratory.

SUBJECTS

226 older adults with chronic LBP.

METHODS

This secondary analysis used baseline data from a prospective cohort study (n = 250). LBP intensity was collected before and after the repeated chair rise test, stair climbing test, and 6-minute walk test; MeP change scores (ie, sum of pretest pain subtracted from posttest pain) and aggregated posttest pain (ie, sum of posttest pain) variables were calculated. LBP-related disability and self-efficacy were measured by the Quebec Back Pain Disability Scale (QBPDS) and Low Back Activity Confidence Scale (LOBACS), respectively. Physical function was measured with the Health ABC Performance Battery. Robust regression with HC3 standard errors was used to evaluate adjusted associations between both MeP variables and disability, self-efficacy, and physical function.

RESULTS

Greater aggregated posttest MeP was independently associated with worse disability (b = 0.593, t = 2.913, P = .004), self-efficacy (b = -0.870, t = -3.110, P = .002), and physical function (b = -0.017, t = -2.007, P = .039). MeP change scores were not associated with any outcome (all P > .050).

CONCLUSIONS

Aggregate posttest MeP was linked to poorer health outcomes in older adults with chronic LBP, but MeP change scores were not. Future studies should consider that the construct validity of MeP paradigms partially depends on the chosen operational definition.

Movement-Evoked Pain Versus Widespread Pain: A Longitudinal Comparison in Older Adults With Chronic Low Back Pain From the Delaware Spine Studies

It is currently unknown which pain-related factors contribute to long-term disability and poorer perceived health among older adults with chronic low back pain (LBP). This investigation sought to examine the unique influence of movement-evoked pain (MeP) and widespread pain (WP) on longitudinal health outcomes (ie, gait speed, perceived disability, and self-efficacy) in 250 older adults with chronic LBP. MeP was elicited with 3 standardized functional tests, while presence of WP was derived from the McGill Pain Map. Robust regression with HC3 standard errors was used to examine associations between these baseline pain variables and health outcomes at 12-month follow-up. Covariates for these models included age, sex, body mass index, resting and recall LBP intensity, LBP duration, depression, pain catastrophizing, and baseline outcome (eg, baseline gait speed). Greater MeP was independently associated with worse 12-month LBP-related disability (b = .384, t = 2.013, P = .046) and poorer self-efficacy (b = -.562, t = -2.074, P = .039); but not gait speed (P > .05). In contrast, WP and resting and recall LBP intensity were not associated with any prospective health outcome after adjustment (all P > .05). Compared to WP and resting and recall LBP intensity, MeP is most strongly related to longitudinal health outcomes in older adults with chronic LBP. PERSPECTIVE: This article establishes novel independent associations between MeP and worse perceived disability and self-efficacy at 12-months in older adults with chronic LBP. MeP likely has biopsychosocial underpinnings and consequences and may therefore be an important determinant of health outcomes in LBP and other geriatric chronic pain populations.

A Novel Movement-Evoked Pain Provocation Test for Older Adults With Persistent Low Back Pain: Safety, Feasibility, and Associations With Self-reported Physical Function and Usual Gait Speed

OBJECTIVES

Low back pain (LBP) is highly prevalent and disabling for older adults. Movement-evoked pain is an emerging measure that may help to predict disability; but is not currently a part of geriatric LBP clinical care. This study tested the safety and feasibility of a new Movement-Evoked Provocation Test for Low Back Pain in Older Adults (MEPLO). We also compared associations between movement-evoked pain via 2 different scoring methods and disability-associated outcomes.

MATERIALS AND METHODS

Thirty-nine older adults with persistent LBP provided baseline recalled and resting pain ratings, self-reported physical function, and usual gait speed. Participants then completed MEPLO, involving 4 tasks essential for functional independence: chair rises, trunk rotation, reaching, and walking. Movement-evoked pain was then quantified using the traditional change score (delta) method of pain premovement to postmovement; and also, a new aggregate method that combines pain ratings after the 4 tasks.

RESULTS

No safety or feasibility issues were identified. Compared with the delta score, the aggregate score was more strongly associated with self-reported physical function (beta: -0.495 vs. -0.090) and usual gait speed (beta: -0.450 vs. -0.053). Similarly, the aggregate score was more strongly associated with self-reported physical function than recalled and resting pain (beta: -0.470, -0.283, and 0.136, respectively).

DISCUSSION

This study shows the safety and feasibility of testing movement-evoked pain in older adults with persistent LBP, and its potential superiority to traditional pain measures. Future studies must validate these findings and test the extent to which MEPLO is implementable to change with geriatric LBP standard of care.