ABSTRACT
BACKGROUND: Virtual reality (VR) has demonstrated efficacy for distraction from pain-related thoughts and exposure to feared movements. Little empirical VR research has focused on chronic pain management. OBJECTIVE: The purpose of this study was to examine the feasibility of VR as an adjunctive intervention for Veterans with chronic pain. We designed a hierarchy ranging from low-intensity pain distraction to high-intensity movement-based exposure for this purpose. VR apps were mapped onto the hierarchy. METHODS: Sixteen Veterans receiving inpatient chronic pain rehabilitation participated in daily VR sessions over a 3-week period. Trajectories across the distraction-to-exposure hierarchy and Veteran-reported intensity ratings were described and evaluated over time. Minimum clinically important differences (MCIDs), pre-post effect sizes, and 95% confidence intervals were examined for fear of movement using the Fear of Daily Activities Questionnaire (FDAQ) and Pain Outcomes Questionnaire-VA (POQ-VA; fear scale). This approach was applied to secondary outcomes: POQ-VA (pain intensity, interference, negative affect), Pain Catastrophizing Scale, and Patient-Specific Functioning Scale (PSFS). Session attendance, completion, and VR experiences were described. RESULTS: Ten of 14 Veterans (71%) who participated in three or more VR sessions completed the distraction-to-exposure hierarchy. Only three trajectories emerged more than once. Due to high completion rates, Veterans that completed the hierarchy could self-select nonhierarchy apps. Veterans rated all hierarchy levels (low, medium, high) near medium intensity. Self-selected activities were rated as high intensity. For kinesiophobia, six Veterans (38%) exceeded the MCID on the FDAQ and a small effect size improvement was observed (Cohen d=-0.35). The confidence interval (95% CI -0.71 to 0.01) indicated the possibility of a null effect. The POQ-VA fear scale yielded no effect (Cohen d=0.06, 95% CI -0.43 to 0.54). For secondary outcomes, Veterans exceeding MCID were calculated with complete data: pain intensity (1/15, 7%), pain catastrophizing (5/14, 36%), and patient-specific functioning (10/15, 67%). Effect sizes were large for patient-specific functioning (Cohen d=1.14, 95% CI 0.50-1.78), medium for mobility interference (Cohen d=-0.56, 95% CI -0.96 to -0.16), and small for pain intensity (Cohen d=-0.40, 95% CI -0.69 to -0.12) and catastrophizing (Cohen d=-0.41, 95% CI -0.79 to -0.02). No effects were observed for interference in daily activities (Cohen d=0.10, 95% CI -0.27 to 0.47) and negative affect (Cohen d=0.07, 95% CI -0.26 to 0.40). Veterans attended 85.2% (98/108) of VR sessions and completed 95% (93/96) of sessions attended. Twenty-minute sessions were rated as too short. No significant adverse events were reported. CONCLUSIONS: Findings support the feasibility of VR as an adjunct for Veterans with chronic pain. However, the hierarchy will require modification, as evidenced by homogeneous intensity ratings. Veteran-selected activities presented the highest intensity ratings, largest outcome effect size (PSFS), and MCID. This highlights the important role of utilizing Veteran stakeholders in hierarchy modification, design of VR interventions, and outcome selection.
ABSTRACT
BACKGROUND: A key concern for people with chronic pain is experiencing increased pain and/or re-injury. Consequently, individuals with chronic pain can develop a maladaptive fear of movement that leads to adverse functional consequences. A primary goal of chronic pain rehabilitation is re-engagement in feared movements through exposure. This is often challenging since safe movement can be uncomfortable. Virtual environments provide a promising opportunity to safely and gradually expose Veterans to movements that are avoided in the real world. The current study will utilize multiple virtual reality (VR) applications (APPs) of varying the intensity levels ranging from passive distraction from pain to active exposure to feared movement. The primary aims of this pilot are to examine VR as an adjunctive nonpharmacological intervention to assist with the adoption and implementation of skills to decrease fear of movement and increase overall functioning among Veterans with chronic pain. Second, to build a hierarchy of VR APPs to assist in gradual exposure to feared movements. METHODS: This study will be conducted in the Chronic Pain Rehabilitation Program (CPRP) at the James A. Haley Veterans Hospital, a unique inpatient program within the VA system. Participants will include up to 20 Veterans who receive a VR intervention as part of their physical therapy. A rating form containing qualitative and quantitative experiences will be administered following each VR session to assess feasibility and to provide descriptive information for the proposed hierarchy. Effect sizes will be calculated from intake and discharge measures for the primary outcome fear of movement and secondary pain and functional outcomes. DISCUSSION: This study will inform the feasibility of a randomized controlled trial examining the clinical utility of using VR to reduce fear of movement and increase function among Veterans with chronic pain. VR has the advantage of being easily implemented both within VA healthcare settings as well as in Veterans' own residences, where engagement in ongoing self-management approaches is often most challenging. Presumably, VR that is matched to patient needs, progresses in intensity, immerses Veterans in the applications, and is perceived positively by Veterans, will result in positive functional outcomes.
