Local infiltration analgesia does not have benefits in fast-track hip arthroplasty programmes: a double-blind, randomised, placebo-controlled, clinical trial.

Background: Multimodal analgesia regimes including local infiltration analgesia (LIA) have been successfully applied in fast-track hip arthroplasty programmes. LIA's contribution to the analgesic effect in hip arthroplasty has been questioned. Our study sought to determine the analgesic efficacy of LIA in THA surgery in a fast-track programme.

Methods: Patients diagnosed with hip osteoarthritis scheduled for arthroplasty were randomised to receive LIA (120 ml ropivacaine 0.2% plus epinephrine 0.5 µ/ml) or saline as a part of a multimodal analgesia regime. The surgical team, the nursing staff, and patients were all blinded regarding patient allocation throughout the study. The primary outcome was pain assessed as a continuous variable using the visual analogue scale (VAS) at 4, 8, 24 and 48 hours postoperatively. Secondary outcomes included the amount of analgesic rescue consumption, complications and length of hospital stay.

Results: A total of 63 patients were interviewed and agreed to participate in the study. No statistically significant differences were found between groups for pain measurements at 4, 8, 12, 24 and 48 hours after surgery. There were also no differences in rescue medication consumption, complications, or length of stay.

Conclusions: Our results suggest LIA (ropivacaine plus epinephrine, single shot) has no effect in pain management and has not shown benefits for early ambulation in primary THA surgery. Further research is needed to establish the optimal multimodal analgesia regime for THA fast-track programmes.

Clinical Trial Registration: Clinicaltrials.gov (NCT03513276).