Supra-inguinal fascia iliaca block versus peri-capsular nerve group (PNEG) block for pain management in patients with hip fracture: A double-blind randomised comparative trial

Background: Regional analgesia has been recommended to alleviate pain caused by hip fractures. Both the supra-inguinal fascia iliaca block (S-FIB) and the peri‑capsular nerve group (PENG) block provide better analgesia than conventional fascia iliaca block for patients with hip fractures, but which one is superior remains equivocal. This study aimed to determine the superiority of S-FIB or PENG block for patients awaiting hip surgery.

Methods: In this prospective, double-blind, randomised comparative trial, patients with hip fractures awaiting operation were randomly allocated to receive either S-FIB with 30 ml 0.35 % ropivacaine or PENG block with 20 ml 0.35 % ropivacaine. Primary outcomes were pain scores (numeric rating scale, NRS, 0-10) at rest and during passive movement 30 min after nerve block. Secondary outcomes included pain scores at rest and during movement 10 and 20 min after nerve block and during positioning for spinal anaesthesia, time spent for performing nerve block and spinal anaesthesia, and the quality of positioning for spinal anaesthesia.

Results: One-hundred patients were enrolled and 91 patients completed the trial (S-FIB group n = 46, PENG group n = 45). No significant difference was noted between these two groups in the pain scores (median [interquartile range]) either at rest (0 [0-0] vs 0 [0-0], P = 0.151) or during passive movement (3 [1-6] vs 3 [2-5], P = 0.99) at 30 min after nerve block. However, within-group analysis revealed that a significant reduction in pain score at rest was noted as early as 20 min after PENG block while that was noted only at 30 min after S-FIB. In addition, less time was required to perform PENG than S-FIB the block (3.1 [2.3-3.9] vs. 4.6 [3.1-5.6] minutes, P < 0.001).

Conclusions: Our result suggests that with a lower dose of local anaesthetic, a shorter procedure time and earlier analgesic effect, PENG block may be preferred to S-FIB for patients with hip fracture awaiting surgery.