Comparison of Lumbar Epidurals and Lumbar Plexus Nerve Blocks for Analgesia Following Primary Total Hip Arthroplasty: A Retrospective Analysis

Abstract

Background: Total hip arthroplasty (THA) is associated with significant postoperative pain. Both lumbar epidurals and lumbar plexus nerve blocks have been described for postoperative pain control, but it is unclear if one technique is more beneficial.

Methods: Using electronic medical records, a randomly selected, cohort of 58 patients with lumbar epidurals were compared with 58 patients with lumbar plexus nerve blocks following primary THA. The primary end point was 48-hour postoperative opiate consumption. Secondary end points included time of first ambulation, distance ambulated, level of assistance with ambulation, presence of side effects, and time to discharge. Descriptive statistics were calculated to characterize subjects in the different block-type groups. Comparisons in morphine consumption were conducted using linear mixed models. Primary and secondary end points were examined in multivariable models.

Results: Patients with lumbar plexus blocks consumed less opiates at 24, 36, and 48 hours relative to patients that received lumbar epidural catheters (P = .047, .002, and .002, respectively). Patients with lumbar plexus blocks ambulated earlier (24.6 ± 2.01 hours vs 31.7 ± 3.01 hours) and farther relative to patients with epidurals (P < .001 for both) and had discharge orders written earlier (58.2 ± 6.68 hours vs 73.6 ± 6.35 hours).

Conclusion: In comparison to lumbar epidural catheters, lumbar plexus nerve blocks are an effective pathway for postoperative pain control following primary THA. Furthermore, this clinical pathway expedites physical rehabilitation and is more compatible with postoperative prophylactic anticoagulants.

Keywords: analgesia; arthroplasty; epidural; nerve block; pain; postoperative.

Copyright © 2016 Elsevier Inc. All rights reserved.

Figures

Fig. 1.

Study overview.

Fig. 2.

Cumulative opioid consumption over time. Opioid consumption was decreased at 24, 36, and 48 hours postoperatively in patients with lumbar plexus blocks compared with lumbar epidurals. The dark line represents median opioid consumption in intravenous morphine equivalents (mg). Boxes represent the 25th–75th percentile for each group. Whiskers extend to 1.5 times the interquartile range from the 25th–75th percentile. *P < .05; **P < .01 (both after adjusting for multiple comparisons).

Fig. 3.

Distance ambulated by patients on each postoperative day (POD). Patients with a lumbar plexus block ambulated farther than patients with epidurals at all examined time points. The dark line represents the median distance ambulated (feet). Boxes represent the 25th–75th percentile for each group. Whiskers extend to 1.5 times the interquartile range from the 25th–75th percentile. *P = .001; **P < .001.