BMJ · IF 55.1 · September 30, 2026 · LoE III
Early national comparison of robotic versus conventional knee replacements for arthritis using National Joint Registry data: target trial emulation study
Hasan Raza Mohammad, Andrew Judge, Xavier Luke Griffin, David W. Murray — Queen Mary University of London
This UK National Joint Registry study compared early revision rates after robot-assisted versus conventional knee replacement (2018 to 2024), analysing total and partial (unicompartmental) knee replacements separately and using propensity score matching within a target trial emulation framework. In the unmatched Results, five year implant survival for total knee replacement was about 98.5% conventional versus 98.6% robotic (hazard ratio 1.03, 95% CI 0.86 to 1.22). Cause specific revisions and intraoperative complications also did not differ significantly in the matched cohorts, although mean follow-up in the robotic group was only 2.5 years.
AI summary · from the full text · reviewed by Pukhraj Gaheer, Medical Student, Queen's University before publishing
Why it mattersWith the NHS planning a large, costly expansion of robotic surgery, this is the largest early real-world signal that robotic knee replacement has not yet reduced revision risk.
Conclusion strengthInconclusive
Fills a stated gap in Surgical Management of Osteoarthritis of the Knee (2022) and how many patients this affects, offset by the intervention is not described well enough to reproduce and important imbalance remained after adjustment.
Presenting this at rounds? Start here
- ?Given no early revision difference and an added cost of roughly £1000 to £2500 per case, which patients, if any, would you counsel toward robotic knee replacement, and what would you tell them about expected benefit?
- ?Should robotic assistance be prioritised for unicompartmental knee replacement (higher baseline revision risk) over total knee replacement, and what longer term outcomes would you want before changing practice?