CE: Assessing Movement-Evoked Pain

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.

Evaluating peripheral neuromuscular function with brief movement-evoked pain

Movement-evoked pain is an understudied manifestation of musculoskeletal conditions that contributes to disability, yet little is known about how the neuromuscular system responds to movement-evoked pain. The present study examined whether movement-evoked pain impacts force production, electromyographic (EMG) muscle activity, and the rate of force development (RFD) during submaximal muscle contractions. Fifteen healthy adults (9 males; age = 30.3 ± 10.2 yr, range = 22-59 yr) performed submaximal isometric first finger abduction contractions without pain (baseline) and with movement-evoked pain induced by laser stimulation to the dorsum of the hand. Normalized force (% maximal voluntary contraction) and RFD decreased by 11% (P < 0.001) and 15% (P = 0.003), respectively, with movement-evoked pain, without any change in normalized peak EMG (P = 0.77). Early contractile RFD, force impulse, and corresponding EMG amplitude computed within time segments of 50, 100, 150, and 200 ms relative to the onset of movement were also unaffected by movement-evoked pain (P > 0.05). Our results demonstrate that movement-evoked pain impairs peak characteristics and not early measures of submaximal force production and RFD, without affecting EMG activity (peak and early). Possible explanations for the stability in EMG with reduced force include antagonist coactivation and a reorganization of motoneuronal activation strategy, which is discussed here.NEW & NOTEWORTHY We provide neurophysiological evidence to indicate that peak force and rate of force development are reduced by movement-evoked pain despite a lack of change in EMG and early rapid force development in the first dorsal interosseous muscle. Additional evidence suggests that these findings may coexist with a reorganization in motoneuronal activation strategy.

CE: Overcoming Movement-Evoked Pain to Facilitate Postoperative Recovery

ABSTRACT

Severe postoperative movement-evoked pain (MEP) can be immobilizing, instilling in patients the fear that further activity will produce unbearable pain. This impedes healing and restoration of function while also extending time to recovery. Therefore, it is critical to manage MEP effectively through timely evaluation and comprehensive care planning. This article builds on recent calls to standardize testing of MEP to inform care planning in a way that both reduces pain and improves functioning. Subsequent reassessment of MEP can guide the refinement of therapy. Although this approach may seem intuitive, it challenges common practices that focus too heavily on pain intensity, resulting in overtreating, undertreating, or not treating pain, while ignoring the risks of immobility and the importance of movement for improving functional capacity. The authors propose a multifaceted approach to overcoming MEP that nurse clinicians, educators, researchers, and compliance professionals can use to enhance the quality and safety of nursing practice.

The effects of pain science education plus exercise on pain and function in chronic Achilles tendinopathy: a blinded, placebo-controlled, explanatory, randomized trial

ABSTRACT

Exercise is the standard of care for Achilles tendinopathy (AT), but 20% to 50% of patients continue to have pain following rehabilitation. The addition of pain science education (PSE) to an exercise program may enhance clinical outcomes, yet this has not been examined in patients with AT. Furthermore, little is known about how rehabilitation for AT alters the fear of movement and central nervous system nociceptive processing. Participants with chronic AT (N = 66) were randomized to receive education about AT either from a biopsychosocial (PSE) or from a biomedical (pathoanatomical education [PAE]) perspective. Simultaneously, all participants completed an exercise program over 8 weeks. Linear mixed models indicated that there were no differences between groups in (1) movement-evoked pain with both groups achieving a clinically meaningful reduction (mean change [95% CI], PSE: -3.0 [-3.8 to -2.2], PAE = -3.6 [-4.4 to -2.8]) and (2) self-reported function, with neither group achieving a clinically meaningful improvement (Patient-Reported Outcomes Measurement Information System Physical Function-PSE: 1.8 [0.3-3.4], PAE: 2.5 [0.8-4.2]). After rehabilitation, performance-based function improved (number of heel raises: 5.2 [1.6-8.8]), central nervous system nociceptive processing remained the same (conditioned pain modulation: -11.4% [0.2 to -17.3]), and fear of movement decreased (Tampa Scale of Kinesiophobia, TSK-17: -6.5 [-4.4 to -8.6]). Linear regression models indicated that baseline levels of pain and function along with improvements in self-efficacy and knowledge gain were associated with a greater improvement in pain and function, respectively. Thus, acquiring skills for symptom self-management and the process of learning may be more important than the specific educational approach for short-term clinical outcomes in patients with AT.