What is the patient experience following revision knee replacement: A systematic review and meta-analysis of the medium term patient reported outcomes.

Aims: Revision knee replacement is an increasingly common procedure, however, information on patient-focused outcomes is limited. This systematic review and meta-analysis aimed to investigate the medium-term patient reported outcomes following a revision knee replacement.

Methods: We performed a systematic review of MEDLINE and EMBASE (from inception to 1st March 2021) for articles reporting five year or greater patient reported outcome measures (PROMs) following revision knee replacement. A meta-analysis of PROMs data was undertaken using the Standardised Mean Difference (SMD). Quality of methodology was assessed using Wylde's non-summative four-point system. The study was registered with PROPSERO (CRD42021199289).

Results: A total of 23 studies met the inclusion criteria containing 2414 patients at a mean minimum follow-up of 74 months (60-122). The reporting of PROMs were poorly standardised with several PROMs being used. The most commonly reported patient reported outcome was the Knee Society Score reported in 65% of studies (15/23). A meta-analysis of 629 eligible patients undergoing revision knee replacement revealed a significant improvement in pre-operative state with a SMD 2·05 95% CI 0.87, 3.23.

Conclusion: This systematic review has found a significant and sustained improvement in patient-reported outcomes following a revision knee arthroplasty beyond five years. We found a variation in the usage and administration of PROMs which hinders a clear synthesis of results. Furthermore, the PROMs have not been robustly tested for validity in the context of a revision knee replacement.