Optimizing Pain Self-Management in Total Knee Arthroplasty

The purpose of this study is to investigate the efficacy of a positive affect enhancing intervention designed to reduce pain and augment reward system function in knee osteoarthritis (KOA) patients undergoing total knee arthroplasty (TKA). The scientific premise is that patient use of a positive emotion generative practice - savoring meditation, which has been demonstrated to reduce pain in experimental laboratory settings, enhanced with a pain neuroscience education component about reward system dysfunction as a chronic pain mechanism - is optimally suited to reduce postsurgical pain and augment reward system functioning relative to a Pain Self-Management and Education (PSME) condition. We will randomize 150 patients with KOA undergoing unilateral TKA to a brief, 4-session (20-30 minutes each) course of Savoring Meditation (SM; n = 75) or PSME (n = 75) delivered remotely by trained interventionists in a one-on-one format. We will assess pain and as well as pain-related risk and protective factors both via questionnaire and via weeklong ecological momentary assessment (EMA) data bursts on the following schedule: baseline, post-surgery, and 3-month follow-up. In addition, participants will attend laboratory testing sessions at baseline and 6-weeks post-surgery, during which affective pain modulation and electroencephalographic (EEG) brain biomarkers associated with pain and affect will be recorded. Participants in SM be encouraged to practice their savoring for 5 minutes/day during the week following surgery, as well as to use it to manage pain flares in a self-directed manner.

Total knee arthroplasty (TKA) is an increasingly utilized, end-stage, cost-effective treatment for knee osteoarthritis (OA), one of the leading causes of disability worldwide (Felson, 2009) whose hallmark symptoms include pain, stiffness, limited range of motion, and physical mobility limitations (NIAMS, 2019). The mechanisms of pain in OA, like most chronic pain conditions, are complex, multifaceted, and involve both central and peripheral sensitization (Bharde et al., 2021), as well as reward system dysfunction (Wang & Ni, 2022). Despite its overall efficacy, a significant portion of patients with TKA (10-34%) continue to experience painful joints following the procedure (Beswick et al., 2012), while an estimated 20% are dissatisfied with the outcome of their procedure (Bourne et al., 2010; Springer & Sotile, 2020). Further, an estimated 20% experience significant post-operative psychological distress in the months following surgery, which longitudinally predicts poorer functional outcomes (Cremeans-Smith et al., 2011). TKA on average fails to improve pain and function to a level comparable to the general population, or to the level achieved by other joint replacement procedures (i.e., hip arthroplasty) (Jones et al., 2007; Linsell et al., 2006). These limitations highlight an urgent need to investigate safe and scalable strategies to improve TKA outcomes. Psychosocial processes have a clinically meaningful role in shaping TKA outcomes. Well-established presurgical cognitive and affective risk factors include pain catastrophizing (Lewis et al., 2015; M. Sullivan et al., 2011), kinesiophobia (Filardo et al., 2017), poor outcome expectations (M. Sullivan et al., 2011; Tilbury et al., 2018) and reward system dysfunction (Lewis et al., 2015). Meanwhile, emerging research suggests that positive, resilience-related factors such as positive affect, vitality, vigor, social support, self-efficacy, and global, trait-like resilience (Nwankwo et al., 2021) predict more favorable TKA outcomes (Cremeans-Smith et al., 2022; Edwards et al., 2022). Major Gap in Knowledge Despite known, modifiable psychological risk and resilience factors known to impact TKA outcomes, only recently have psychosocial processes in TKA been targeted in clinical trials. We are aware of a handful of investigations which have variously employed psychoeducation, guided imagery, motivational interviewing, and cognitive-behavioral approaches, which have demonstrated modest to poor efficacy in impacting postsurgical pain and function (Bay et al., 2018). Pain neuroscience education (PNE) is a relatively recent psychosocial intervention approach to chronic pain that educates patients on the modern neuroscientific understanding of mechanisms (e.g., central and peripheral sensitization), whose efficacy appears to be optimized when combined with an additional active treatment (e.g., physical therapy) informed by the patent's reconceptualization of pain (away from biomedical or biomechanical understanding and towards a modern neuroscientific understanding) achieved through PNE (Moseley & Butler, 2015; J. A. Watson et al., 2019). Initial studies on PNE alone in TKA patients show a favorable effect on patient satisfaction with the TKA procedure (Louw et al., 2019) and psychosocial risk factors including pain catastrophizing and kinesiophobia (Lluch et al., 2018) but no effect on pain or function. How Proposed Work Will Fill the Gaps The present study will address major gaps in knowledge by testing a novel prophylactic psychological intervention for TKA patients that targets reward system dysfunction, a central driver of chronic pain states. Specifically, we will test a novel Savoring Meditation (SM) intervention, which teaches patients how to augment positive affective functioning via meditating on a positive autobiographical memory. In addition, using a pain neuroscience education framework, SM will also educate participants on the neurophysiological basis for engaging in savoring meditation. Specifically, we will educate patients about the reward system in the brain, and how deficits in reward system functioning serve to maintain pain. Subsequently, we will explain to patients that savoring meditation has been empirically shown and is optimally suited to reduce pain vis-a-vis augmented reward system functioning. Patients randomized to SM will engage in 4 sessions of SM with a trained interventionist. They will be encouraged to use their SM skills in the postsurgical period to manage pain. We will compare the efficacy of SM to a Pain Self-Management and Education (PSME) condition, wherein patients will learn about biological, psychological, and social drivers of pain. The PSME condition will control for therapeutic alliance and treatment expectancies. We hypothesize that patients who undergo 4 sessions of SM will demonstrate reduced clinical pain and prescription opioid use across major assessment timepoints (post-treatment, 6-weeks, and 3-months), relative to PSME. Reward system function measured via self-report, affective pain modulation task performance, and electroencephalographic (EEG) based biomarkers will be investigated as a secondary outcome.

A 4-session meditation intervention in which participants are trained to generate positive emotional states and focus their awareness on those states throughout the meditation.

Participants will learn about pain neuroscience and will learn/practice a positive emotion generative practice (Savoring Meditation).

Average pain intensity on numeric rating scale, aggregated across Ecological Momentary Assessment observations

Inclusion Criteria: 18-85 years old. Have a physician-confirmed treatment plan to undergo unilateral TKA along with physician-confirmed knee osteoarthritis diagnosis. Willingness and ability to comply with scheduled sessions and study procedures Exclusion Criteria: Member of a vulnerable population including pregnant women, children, prisoners, cognitively impaired, and non-English-speaking subjects. Current unstable, severe medical comorbidity. Current severe psychiatric comorbidity (e.g., schizophrenia, psychosis, or other unstable psychiatric disorder). Current severe alcohol or substance use disorder. Weekly or more frequent use of opioids in the past 30 days (other than tramadol and/or codeine) for therapeutic or non-therapeutic purposes. Other surgery of the affected knee in the last 6 months. Previous TKA.

Deidentified data will be shared upon reasonable request from other researchers, and after a data use agreement has been executed between institutions.

Data will become available after the study is complete and the primary outcomes manuscript has been published.