# MIKROBE: a feasibility study for a randomised controlled trial of one-stage or two-stage surgery for prosthetic knee infection

## TL;DR

This study assessed the feasibility of a trial comparing one-stage and two-stage surgery for knee infections and found it not feasible with the current design.

## Contribution

The study provides insights into the challenges of designing a randomized controlled trial for prosthetic knee infection surgeries.

## Key findings

- Only 3 out of 136 screened patients were randomized, indicating poor recruitment.
- Qualitative feedback highlighted issues with trial processes and patient acceptance.
- A larger trial with the current design is deemed infeasible.

## Abstract

Total knee replacement surgery is common, with over 107,000 operations performed in the UK in 2019. After surgery, about 1% of patients develop a deep infection, known as a prosthetic joint infection. Two types of operations, one- or two-stage revision surgery, are routinely performed to treat the infection. Re-infection rates are similar, but there is uncertainty regarding longer-term outcomes for patients. The aim of this study was to establish the feasibility of conducting a future randomised controlled trial that will compare clinical and cost-effectiveness of one-stage versus two-stage revision knee surgery for prosthetic joint infection.

Following eligibility screening, consenting patients took part in an audio-recorded consultation with their surgeon and were then randomised on a 1:1 allocation to one-stage or two-stage revision surgery. Patient-reported outcome measures were administered at baseline and 3 and 6 months postoperatively. Embedded qualitative work with patient participants and nonparticipants and with surgeons to understand the acceptability of trial processes and involvement was undertaken. Patient and public involvement and engagement activities were conducted throughout the study.

Of 136 patients screened, only 3 were randomised and had surgery as part of the study. Qualitative data were collected from the three participants, as well as from two eligible patients who declined participation and two who withdrew from participation after the initial patient-surgeon consultation. Five surgeons took part in qualitative interviews prior to study end.

This study indicated that a larger randomised controlled trial evaluating one-stage versus two-stage revision knee surgery for prosthetic joint infection is not feasible with the current straightforward randomised controlled trial design. Future research needs to consider the most appropriate study design and methodology to address this important research question.

No.: NCT04458961.