ABSTRACT
Purpose: Disability in knee osteoarthritis (KOA) is known to be largely due to pain, the mechanism of which is complex and multidimensional with alterations in nociceptive processing in the peripheral and central nervous system (CNS) leading to persistent pain. Current clinical practice guidelines for KOA provide strong recommendations for education and exercise including land-based or mind-body approaches. However, individually these strategies are only moderately effective. One potential reason for this is a lack of understanding of their underlying mechanisms and how their combination might impact nervous system modulation. Neuromuscular exercise is known to improve lower extremity strength. Mind-body approaches as well as pain neuroscience education (PNE) are uniquely positioned to potentially reverse CNS adaptations by inducing positive neuroplastic changes and improving descending modulation of pain resulting in decreased pain. To our knowledge, neuromuscular exercise, mind-body techniques, and PNE have not been studied in combination. We therefore aimed to establish the feasibility of an intervention consisting of these three elements referred to as Pain Informed Movement (PIM). The results of this study will inform necessary modifications for a two-arm pilot randomized controlled trial (RCT). Method(s): This study was a single-arm feasibility trial with a nested qualitative component and the primary feasibility outcome of complete follow up. Inclusion criteria: age >= 40 years, KOA clinical diagnosis or people fulfilling the NICE diagnostic criteria, and average pain intensity >=3/10 on the numeric pain rating scale. PIM consisted of twice weekly in-person exercise sessions and a third home exercise session for 8 weeks. In addition, PNE, provided as online videos, covered the following topics: purpose of pain, neurophysiological changes associated with pain, movement guidelines when pain persists, mind-body techniques to impact neurophysiology and support moving with ease that included breath awareness and regulation, muscle tension regulation, awareness of pain related thoughts and emotions, and relaxation. The mind-body techniques and the PNE topics were implemented during the group exercise sessions that included evidence-based neuromuscular exercises aimed at improving sensorimotor control and functionality of the knee joint. Participants completed questionnaires and in-person assessments at baseline and at program completion. Assessments included weight and height, chair stands as a measure of functional leg strength, and conditioned pain modulation to assess efficiency of the descending modulatory pathways. Participants also had their blood drawn to monitor changes in brain derived neurotrophic factor (BDNF), a marker of neuroplasticity. Questionnaires included the Pain Catastrophizing Scale, Hospital Anxiety and Depression Scale, the Knee Injury and Osteoarthritis Outcome Score - function and pain subscales, Chronic Pain Self Efficacy scale, pain intensity rated in the past 24 hours, the past week, and worst pain in the past 24 hours. Secondary feasibility outcomes included acceptability of the intervention, burden of assessments, recruitment rate, compliance rate, adherence rate, and self-reported adverse events. Feasibility findings were evaluated against a-priori success criteria. In the qualitative component, participants were invited to an online focus group and were asked about their experience and perceptions of the program. Interview recordings were analyzed using thematic content analysis to identify suggestions for program modification. Result(s): In total, 19 participants (mean age 63.3 years (SD 10.5), 73% female) were enrolled, with a complete follow up rate of 74% (n=14) for our primary objective, indicating that modifications would be needed to proceed. Of the 5 dropouts, only one was study related. We will be adding additional inclusion criteria of: ability to get up and down from the floor independently, and no use of mobility aids. Adherence to in-person treatment sessions was 91%, hich indicates proceeding with the protocol for the next phase (i.e., pilot RCT). Some absences were due to unmodifiable factors (e.g., COVID-19). We will make protocol amendments for the purpose of improving the adherence rate to include 'no planned absences'. All other success criteria were met: recruitment rate, compliance to exercise sessions, program acceptability, duration, frequency, and delivery, likelihood of recommending the program to others and taking the program again, burden, and adverse events (Table 1). Analysis of the focus groups revealed that the video content pertaining to the mind-body techniques would benefit from on screen demonstrations by the instructor to assist with participants' execution of breath and muscle tension regulation. The majority of participants improved in most of the physical assessment outcomes and questionnaires (Table 2). Conclusion(s): The PIM program is feasible, acceptable, not burdensome, does not cause adverse events, and had an excellent compliance rate. Minor modifications are needed to optimize enrolment and adherence rates. Although improvements in pain, function, and psychological measures were observed, the feasibility nature of this study precludes any conclusions regarding efficacy. A pilot two-arm RCT will be conducted to establish the feasibility and explore potential effects of PIM when compared to conventional neuromuscular exercise and standard OA education. [Formula presented] [Formula presented]Copyright © 2023