Partial knee replacement more cost-effective than TKR for knee osteoarthritis

Oxford, UK: Partial knee replacement (PKR) should be considered the first choice for patients with late-stage isolated medial compartment osteoarthritis -- is the key takeaway from a study by Oxford researchers published in the journal The Lancet.

This is based on the finding that PKR had lower costs and better cost-effectiveness during the 5-year study period. Whilst both total knee replacement (TKR) and PKR were found to be equally effective, offered similar clinical outcomes and resulted in a similar incidence of complications and re-operations.

Knee replacement is an effective, common procedure for the patients with osteoarthritis of the knee. There are two main surgical options for late-stage medial compartment osteoarthritis of the knee -- total knee replacement or partial knee replacement. The best option for the treatment remains uncertain due to the lack of evidence to inform the cost-effectiveness and clinical effectiveness of either management approach.

In this multicenter, pragmatic randomized controlled trial, the researchers assessed 62 patients for their eligibility, of whom 431 (45%) patients were excluded (121 [13%] patients did not meet the inclusion criteria and 310 [32%] patients declined to participate) and 528 (55%) patients were randomly assigned to groups. This was done across 27 UK sites from Jan 18, 2010, and Sept 30, 2013. The eligible patients were randomly assigned in the ratio 1:1 to receive PKR or TKR by the surgeons who were either expert in and willing to perform both surgeries or by a surgeon with particular expertise in the allocated procedure.

Key findings of the study include:

• 94% of participants responded to the follow-up survey 5 years after their operation.


• At the 5-year follow-up, no difference was found in OKS between groups.


• PKR was more effective (0·240 additional quality-adjusted life-years) and less expensive (−£910) than TKR during the 5 years of follow-up.

"This finding was a result of slightly better outcomes, lower costs of surgery and lower follow-up health-care costs with PKR than TKR," wrote the authors.

"We suggest that PKR should be considered the first choice for patients with late-stage isolated medial compartment osteoarthritis," concluded the authors.