At 12 months, the costs in the TKR plus non-surgical treatment group were more than double of those in the non-surgical group.
However, 24 months the costs of the TKR plus non-surgical treatment were not significantly different from the non-surgical group. This is due to several of the patients in the non-surgical group who underwent TKR at a later time - 1 in 3 in the non-surgical group went on to have a TKR in the next two years.
Although TKR plus non-surgical treatment seemed to be more effective, it was not more cost-effective than non-surgical treatment with the option of surgery at a later time.
Finally, as results were sensitive for adjustment for covariates and imputation of missing values, more research with longer periods of follow-up is necessary.