The Manual Therapy and Strengthening for the Hip (MASH) Trial: Protocol for a Multisite Randomized Trial of a Subgroup of Older Adults With Chronic Back and Hip Pain

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.

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.

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.