Fat embolism syndrome following the intramedullary alignment guide in total knee arthroplasty.

Fat embolism syndrome (FES) is a well-known complication of total hip arthroplasty (THA). FES occurs less frequently in total knee arthroplasty (TKA) than in THA. A 67-year-old woman developed FES after placement of the intramedullary femoral alignment guide during TKA. The diagnosis is based upon a subtle, but significant change in the oxygen saturation after placement of the guide. This potentially fatal complication may be avoided with a simple precautionary step of intramedullary canal marrow aspiration prior to placement of the alignment guide pin.