Local infiltration analgesia with additional intraarticular catheter provide better pain relief compared to single-shot local infiltration analgesia in TKA

Purpose: Local infiltration analgesia (LIA) has been proven to be efficient in total knee arthroplasty (TKA). However, the effect of single-shot LIA is temporarily limited. The objective of this prospective trial was to investigate if the potential benefits resulting from LIA can be prolonged by a continuous intra-articular perfusion of LIA. The hypothesis of the present study was that the use of an additional continuous intra-articular perfusion delivering LIA would result in less pain and better function compared to single-shot LIA in the immediate post-operative period. Methods: 50 consecutively selected patients undergoing TKA received either a single-shot LIA (S-LIA group, 25 knees) or single-shot LIA combined with a continuous post-operative intra-articular perfusion for three post-operative days (CP-LIA group, 25 knees). VAS (visual analogue scale) for pain, pain medication consumption and flexion ability were recorded postoperatively for 6 days. All patients had the same implant, surgeon and intra- as well as post-operative setting. Results: The VAS score was significantly better for CP-LIA 6 h after surgery and on post-operative day 1, 2 and 6. There was no significant difference with regard to additional opioid consumption or flexion ability of the knee. However, there was a trend of the CP-LIA group requiring less additional opioids over the complete post-operative period compared to the S-LIA group. There were no complications or revisions. Conclusion: LIA combined with an additional intra-articular catheter provides better short-term pain control compared to single-shot LIA. However, no significant differences in terms of knee flexion were observed. This limited benefit should be balanced against the additional costs and the possible higher risk of infection. Level of evidence: Level II.