Ultrasound-Guided Nerve Blocks as Analgesia for Nonoperative Management of Distal Radius Fractures-Two Consecutive Randomized Controlled Trials

Abstract

Objectives: To investigate whether a conventional fracture hematoma block (FHB) or an ultrasound-guided peripheral nerve block has more superior analgesic effect during nonoperative management of distal radius fractures in an emergency department setting. Two peripheral nerve block types were investigated, one at the level of the elbow, or cubital nerve block (CNB), and another an axillary nerve block (ANB).

Design: Two prospective randomized controlled studies were performed to compare the difference in pain intensity during closed reduction of a distal radius fracture between FHB-, CNB-, and, ANB-treated patients.

Setting: Level 2 trauma center.

Patients: One hundred ten patients with radiographic displaced distal radius fractures were randomized. Fifty patients were randomized between FHB and CNB, and 60 patients were randomized between CNB and ANB.

Intervention: FHB, CNB, or ANB. These were performed by 3 physicians new to ultrasound-guided peripheral nerve blocks and trained before onset of this study.

Main outcome measurement: Pain was sequentially measured using an NRS during closed distal radius fracture reduction.

Results: CNB patients experienced less pain during block procedure (P = 0.002), finger trap traction (P = 0.007), fracture reduction (P = 0.00001), after plaster cast application (P = 0.01), and after control radiography (P = 0.01). In our second study, ANB-treated patients reported less pain during block procedure (P = 0.04), during finger trap traction (P < 0.0001), fracture reduction (P < 0.0001), after plaster cast application (P = 0.0001), and after control radiography (P = 0.0005).

Conclusions: Although participating clinicians had minimal expertise using ultrasound-guided peripheral nerve blocks, nonoperative management of distal radius fracture using an ANB was less painful. These block types are expected to completely eradicate sensation the best. Future studies should address technical factors including adequate placement and time to let the block set up, as well as issues such as resource utilization including time and clinician availability to better determine the relative advantages and disadvantages to other analgesia techniques such as the FHB.

Level of evidence: Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.