Both (LIA) and femoral block resulted in similar quality of pain relief after total knee arthroplasty (TKA). The maximal plasma ropivacaine level after LIA seems to be higher than after femoral. Bound and unbound ropivacaine plasma concentration in total hip arthroplasty (THA) was below toxic threshold. The use of ketorolac in LIA may not be safer than other routes of administration.