TOPKAT

The clinical and cost-effectiveness of total versus partial knee replacement in patients with medial compartment osteoarthritis (TOPKAT): 5-year outcomes of a randomised controlled trial.

Beard DJ, Davies LJ, Cook JA, et al. Lancet (London, England) 2019 · PMID 31326135 · doi:10.1016/s0140-6736(19)31281-4

Question

In isolated medial compartment knee osteoarthritis, does partial (unicompartmental) knee replacement give better outcomes and value than total knee replacement?

Design

Pragmatic multicentre NIHR-funded RCT across UK hospitals with 5-year follow-up and economic evaluation.

Patients

Adults with symptomatic end-stage medial compartment osteoarthritis judged suitable for either partial or total knee replacement.

Intervention

Unicompartmental (partial) knee replacement

Comparison

Total knee replacement

Primary outcome

Oxford Knee Score at 5 years

Key result

There was no significant difference in Oxford Knee Score at 5 years, with similar reoperation and complication rates; partial knee replacement was more cost-effective and showed small advantages in some secondary measures.

Limitations

Surgeons could use any implant, so results reflect a range of experience and designs; 5-year follow-up is too short to judge long-term revision differences.

Impact on practice

Supports offering partial knee replacement to suitable patients with isolated medial disease as at least as effective and better value than TKA, to be weighed against the higher revision rates seen in registries.