18 patients with bilateral osteoarthritis of the knee, who were undergoing staged total knee arthroplasty (TKA) with a minimum interval of 3 months, were included in a study comparing two pain control drugs. The order in which patients received continuous femoral nerve block (FNB) and multimodal periarticular soft tissue injection (MPI) was randomized such that they received one after the first-stage operation and the other after the second-stage operation. Over 72 hours post-operatively, there was no difference between the two groups for the amount of morphine consumed, pain at rest and in motion, and in functional outcomes. It was, therefore, concluded that continuous FNB and MPI are equally effective in controlling pain after TKA.