Background: Peripheral nerve block and local infiltration analgesia (LIA) have an increasing role as part of multimodal analgesia for enhanced recovery after total knee arthroplasty (TKA). We hypothesized that the combination of obturator nerve block (ONB) and tibial nerve block (TNB) would reduce pain and opioid consumption more than ONB or TNB alone when combined with continuous adductor canal block and LIA.

Methods: Ninety patients were recruited into the study and received spinal anesthesia, LIA, and continuous adductor canal block. They were further randomized to receive either an ONB (group 1), a TNB (group 2), or both (group 3). The primary outcome was total morphine consumption over the postoperative 24 hours. The secondary outcomes included visual analog scale scores, time to first and total dosage of rescue analgesia, Timed Up and Go test, range of motion, muscle strength test, hospital stay, and patient satisfaction.

Results: Eighty-nine patients completed analysis. The median total morphine consumption during the first 24 postoperative hours was 2 mg (interquartile range [IQR] 0-4) in group 3, 4 mg (IQR 2-8) in group 2, and 6 mg (IQR 6-14) in group 1 (P < .001). Posterior knee pain during the first 24 hours postoperatively was significantly lower in group 3 than in group 1 (P = .006). The ability to ambulate and quadriceps strength were significantly better in group 3 than in the other groups.

Conclusion: The combination of triple nerve block was superior to double nerve block in improving analgesia and functional outcomes in the immediate postoperative period after total knee arthroplasty, when combined with LIA.