Abstract
A number of studies suggest revision of unicompartmental knee replacement (UKR) to total knee replacement (TKR) is straightforward. We hypothesise that this is not always the case in terms of complexity, cost and clinical outcome.
We identified 23 consecutive patients revised from UKR to TKR by 2 consultant surgeons (2005–2008). These were matched by age, sex and comorbidity to a cohort of primary TKRs (42 patients) performed during the same period. Data were collected regarding demographics, cost (surgical time & implants) and 1 & 5-year follow-up of clinical outcome (OKS) and outpatients attended.
There was no statistically significant difference in cost of implants for revision UKR to TKR vs. primary TKR (p=0.08), however operative time was significantly higher in the revision group. One year mean OKS was significantly higher in the primary TKR group (mean 30 vs. 23 p=0.03), but 5-year follow up showed no significant difference (mean OKS 27 vs. 32 p=0.20). The revision group had statistically significantly greater number of follow-up appointments (mean 6 Vs. 2 p<0.0001).
Revision of UKR to TKR is not a universally straightforward procedure, carrying significant overall cost implications. Clinical outcomes, although significantly different at 1 year are almost the same at 5 years.