Erector spinae plane versus fascia iliaca block after total hip arthroplasty: a randomized clinical trial comparing analgesic effectiveness and motor block

Abstract

Background: Ultrasound-guided supra-inguinal fascia iliaca block (FIB) provides effective analgesia after total hip arthroplasty (THA) but is complicated by high rates of motor block. The erector spinae plane block (ESPB) is a promising motor-sparing technique. In this study, we tested the analgesic superiority of the FIB over ESPB and associated motor impairment.

Methods: In this randomized, observer-blinded clinical trial, patients scheduled for THA under spinal anesthesia were randomly assigned to preoperatively receive either the ultrasound-guided FIB or ESPB. The primary outcome was morphine consumption 24 h after surgery. The secondary outcomes were pain scores, assessment of sensory and motor block, incidence of postoperative nausea and vomiting and other complications, and development of chronic post-surgical pain.

Results: A total of 60 patients completed the study. No statistically significant differences in morphine consumption at 24 h (P = 0.676) or pain scores were seen at any time point. The FIB produced more reliable sensory block in the femoral nerve (P = 0.001) and lateral femoral cutaneous nerve (P = 0.018) distributions. However, quadriceps motor strength was better preserved in the ESPB group than in the FIB group (P = 0.002). No differences in hip adduction motor strength (P = 0.253), side effects, or incidence of chronic pain were seen between the groups.

Conclusions: ESPBs may be a promising alternative to FIBs for postoperative analgesia after THA. The ESPB and FIB offer similar opioid-sparing benefits in the first 24 h after surgery; however, ESPBs result in less quadriceps motor impairment.

Keywords: Analgesia; Chronic post-surgical pain; Enhanced recovery after surgery; Hip replacement arthroplasty; Nerve block; Postoperative pain..

Fig. 1.

Ultrasound scans. (A) Fascia iliaca block pre-injection and (B) post-injection, (C) erector spinae plane block pre-injection and (D) post-injection. The red circle indicates the deep circumflex artery, the triangular dotted line indicates the fascia iliaca, the stars indicate the local anesthetic, and the dotted line indicates the needle path. tL3, tL4, and tL5 indicate the transverse process of the third, fourth, and fifth lumbar vertebra, respectively. IOm: internal oblique muscle, ILm: iliacus muscle, IBone: iliac bone, ESm: erector spinae muscle.

Fig. 2.

Consolidated Standards of Reporting Trials (CONSORT) patient flowchart.

Fig. 3.

Pain values at rest and during movement in the first 48 h. NRS: numeric rating scale at rest, mNRS: numeric rating scale during movement, FIB: fascia iliaca block, ESPB: erector spinae plane block.

Fig. 4.

Proposed mechanism of local anesthetic (blue) diffusion. The orange line indicates the middle thoraco-lumbar fascia (mTL), the red line indicates the anterior thoraco-lumbar fascia (aTL), and the yellow line indicates the posterior thoraco-lumbar fascia (pTL). ESm: erector spinae muscle, QLm: quadratus lumborum muscle, Pm: psoas muscle.