Extended Reality Interventions for Osteoarthritis of the Knee and Recovery after Total Knee Arthroplasty: A Systematic Review (Preprint)

<sec> <title>BACKGROUND</title> Non-pharmacologic interventions are important for treating knee pain due to osteoarthritis (OA) or after total knee arthroplasty (TKA). Extended reality (XR) technology may enhance the efficacy of non-pharmacologic treatments including rehabilitation for these indications, but a review of current evidence is needed to evaluate benefits and harms of XR-based interventions. </sec> <sec> <title>OBJECTIVE</title> We conducted a systematic review to assess benefits and harms of XR interventions for pain due to knee OA or recovery after TKA. </sec> <sec> <title>METHODS</title> We searched MEDLINE, Embase, CINHAL, PsycINFO, and Scopus databases from inception to May 2023. Eligible studies included randomized controlled trials (RCTs) that evaluated XR interventions to treat pain due to knee OA or after TKA and reported at least one eligible outcome (eg, pain-related functioning or interference, pain intensity, or adverse events). Risk of bias (RoB) was assessed using the Cochrane RoB 2 tool. Data were abstracted by one reviewer and verified by a second. We classified interventions as either virtual reality (VR, fully immersive) or augmented reality (AR, partially immersive). We used GRADE criteria to determine certainty of evidence (COE) for prioritized outcomes. </sec> <sec> <title>RESULTS</title> We identified eligible RCTs addressing pain due to knee OA (k=5) or recovery after TKA (k=7). All studies were rated some concerns (k=6) or high (k=6) RoB. Sample sizes ranged from 52-306 participants and most (k=8) had a follow-up of ≤3 months. Guiding and engaging physical activity was the primary mechanism of interventions in 11 of the studies and 1 study utilized distraction only. Ten studies assessed pain-related functioning and 11 assessed pain intensity or severity. Two assessed adverse events. In the knee OA group 1 study examined VR and 4 examined AR. Compared with conventional therapy, VR physical activity may result in better pain-related functioning and greater decreases in pain intensity (low COE); evidence is very uncertain on the effects of AR physical activity on pain-related functioning, pain intensity, and adverse events (very low COE). For post-TKA, 2 studies examined VR and 5 examined AR. Compared with standard rehabilitation, AR physical activity may result in better pain-related functioning (low COE), but evidence is very uncertain on its effects on pain intensity and adverse events. The evidence is very uncertain on the effects of VR physical activity on pain-related functioning and pain intensity. </sec> <sec> <title>CONCLUSIONS</title> Trials commonly evaluated XR interventions facilitating physical activity, and most often compared XR to standard, non-XR exercise or rehabilitation. Evidence on benefits and harms of XR interventions to treat pain in knee OA and post-TKA is limited due to methodological concerns, small study size, and lack of reporting on adverse events. Larger high-quality RCTs with longer follow-up are needed to improve understanding of benefits and harms of XR interventions in knee OA or post-TKA. </sec> <sec> <title>CLINICALTRIAL</title> PROSPERO registration number CRD42023439903 </sec>