Local infiltration analgesia (LIA) is promoted as an effective treatment modality for pain control after total knee arthroplasty (TKA) (1). A mixture of drugs is used to provide a multimodal analgesic effect. Previous studies reported that the use of these drugs is safe. After we carefully implemented a LIA study protocol in our practice, concerns raised about patient safety with probably higher infection rates. This forced us to perform an interim analysis after the first 58 cases.

58 patients underwent a unilateral TKA with a standardised LIA protocol (2), which consisted of a mixture of ropivacaine, epinephrine, and triamcinolone acetonide. Complications, knee function and patient satisfaction scores were prospectively recorded during regular outpatient control.

Four patients (6.9%) presented with signs of periprosthetic joint infection (PJI) within two months after surgery. Baseline characteristics were similar between the infected and non infected group. All infections were treated with debridement and retention, and antimicrobial treatment was started. One patient who suffered an infection died during followup. At two years followup all implants could be retained. Knee function and KSS score were acceptable for the patients who suffered PJI.

There is no consensus on the combination of drugs used for LIA. The application of corticosteroids in LIA is reported to be safe (3), but arguable results about the injection of local corticosteroids around knee arthroplasty surgery in the past have raised suspicion in literature (4). Combined with our unacceptable high rate of PJI, we believe that the current body of evidence, with small heterogeneous series, does not support the safe use of corticosteroids in LIA.