Yoeri Bemelmans

Local infiltration analgesia in knee arthroplasty 53 4 Many studies have shown the effects of postoperative LIA [3, 8, 34]. Most of these studies focus on analgesic consumption, early mobilization, pain relief and early dis- charge from hospital [17]. The postoperative pain relief presented in this trial may be comparable to the results from other studies [4, 8, 9, 14]. However, not all results are based on single-shot injections [4]. Many techniques are described in literature, but there is no gold standard in the treatment of pain control after TKA. Most of the studies included single-, continuous [32, 34], intra- or extra-artic-ular infiltrations [3, 7, 26, 30] and with frequent postop-erative injections through an intra- [19, 20] or extra-artic-ular catheter [10] Recent published series consist positive results on the LIA technique with ropivacaine and adrena-line infiltrated intra-operatively with single-shot injections [8, 33]. This trial found comparable results in the literature if it becomes to pain, PONV, early mobilization and dis-charge after single-shot injections of ropivacaine with or without adrenaline. However, also high postoperative pain scores were seen after single-shot injection LIA [34]. One of the limitations in this study, circulating blood levels of ropivacaine were not measured to check for pos-sible considerable chondrotoxicity. Adrenaline reduces potentially toxic blood concentrations of ropivacaine and can extend the effects of the local anaesthetics by keep-ing it localized to the area of injection, but with possible side effects such as tissue necrosis and increased risk of infections, which was found in one patient per group in our series [12, 21, 22, 29, 30]. Both patients were success-fully treated with antibiotics. Other than Andersen et al. [2] reported, a possible risk of considerable chondrotoxic-ity is clinical relevant in case of performing a TKA without resurfacing the patella. Secondly, it can be argued that the absent effect of adren-aline may be explained by a continuous effect of the used optimised pain protocol although both groups received the same pre- peri- and postoperative treatment including the same opioid sparing multimodal oral pain protocol. In contrast to other published trials, ketorolac was not added to the LIA mixture. Etoricoxib was part of the multimodal oral pain protocol, administered 2 h pre- and daily up to postoperative day 14. Thirdly, a comparisonwith a placebo-controlled group that received LIAwith only saline was not made. Given the fact that single-shot LIA is an added value after TKA to cope with postoperative pain relief, LIA should belong to the daily practice during TKA [33]. However, it is unclear which LIAmixture has themost favourable outcomewithminimal side effects. Recently, Xu et al. [33] published their meta-analysis of RCT’s on single-shot LIA in TKA patients. They concluded that single-shot LIA is effective for postoperative pain management in TKA patients with satisfactory short-term safety without any