Pain and Opioid Use Outcome Measures in Knee Arthroplasty Randomized Trials: A Protocol for a Methodological Review

Abstract

Background: Osteoarthritis (OA) is one of the most common degenerative joint diseases that occurs in the elderly population. Total knee arthroplasty is a recognized treatment for end-stage knee OA and is effective in managing pain and improving function. However, postoperative pain and opioid use continue to be major challenges. Clinical trials aiming to study interventions to decrease these twin challenges have used different priorities and varied approaches to measure and report pain and opioid use as clinical outcomes. The purpose of this study is to methodologically review randomized controlled trials on total knee arthroplasties to describe and report the approach to measuring pain and opioid use. Because pain and opioid use are interrelated concepts that, we argue, should not be conceptually separated, we will particularly focus on whether and how pain and opioid use are reported as either a combined outcome or as co-primary outcomes.Methods: This is a protocol for a methodological review of pain and opioid use outcomes used in knee arthroplasty RCTs published in the past 10 years (Jan 1, 2012 – Oct 1, 2022). Eligible studies will be identified by searching MEDLINE, EMBASE, and CENTRAL databases. A systematic review management software, Covidence, will be used to conduct the screening and data extraction stages of the study. Screening and data extraction will be done individually and in duplicate for study inclusion and final analysis. Discussion: Previous studies have outlined potential analytical approaches to combine and report pain scores and opioid use as either co-primary outcomes or one outcome, but no consensus has been reached in the reporting of these two outcomes. This study will add to the literature by methodologically evaluating the literature on pain and opioid use outcomes following a total knee arthroplasty and describe how these two outcomes are reported, with a particular focus on whether and how they are reported as one combined outcome or co-primary outcomes.