Transgluteal Sciatic Hydrodissection vs Nerve Block in the Emergency Department: A Retrospective Outcome Analysis

Sciatica is a debilitating condition seen in the Emergency Department (ED). Ultrasound(US)-guided transgluteal sciatic nerve blocks (TSNB) and hydrodissection (TSNH) are effective for pain reduction but they have not been directly compared in clinical outcomes or adverse events. This study evaluated differences in clinical outcomes, adverse events, and ED return rates between TSNB and TSNH.

This was a retrospective review of patients age ≥18 years treated at two EDs between October 2022 and August 2025 with either a TSNB or TSNH. Patients with recent spinal surgery, bilateral extremity pain, cord impingement symptoms, or dementia were excluded. Patients were grouped by US intervention type (TSNB or TSNH). Outcomes included ED length of stay (LOS) in minutes (min), treatment-related complications, need for inpatient admission and return to the ED within one week of discharge. Bivariate analyses were conducted to determine whether differences existed between groups, with Mann Whitney U testing for continuous variables and Fisher’s exact testing for discrete variables.

A total of 58 patients were included (mean age 54.0±17.1 years, 53.5% female, 58.6% white). Eleven (19.0%) patients were treated with TSNH (saline: n=6; dextrose 5%: n=5) and 47 patients (81.0%) were treated with TSNB (bupivicaine: n=41; ropivicaine: n=6). There was no significant difference in pain medication requirements before or after intervention between TSNH and TSNB groups (p = 0.328) The median ED LOS was similar between the two groups (TSNH: 272 min [IQR: 215-373 min]; TSNB: 311 min [IQR: 197-484 min]; p=0.453). Two patients in the TSNB group experienced a transient foot drop. There were no complications in the TSNH group. One patient (9.1%) in the TSNH group and 7 patients (14.9%) in the TSNB group required admission due to intractable symptoms (p=0.525). One patient (9.1%) in the TSNH group and 6 patients (12.8%) in the TSNB group had an unplanned return visit to the ED (p=0.602).

TSNB and TSNH resulted in similar ED length of stay, return visits, and admission rates for patients presenting with sciatica. TSNB carried a small risk of transient foot drop, suggesting TSNH may provide a safer alternative when minimizing motor involvement is a priority. These findings support the need for larger prospective studies to understand differences in safety and effectiveness.