Distal radius fractures (commonly called Colles’ or Smith’s fractures) are often encountered in the emergency department, with options for analgesia revolving around either a hematoma block, intravenous opioids, or procedural sedation, particularly for closed reduction. A novel single-injection nerve block technique known as the retroclavicular approach to the infraclavicular region (RAPTIR) may be the ideal method for excellent pain control, allowing for nearly painless closed reduction and lasting analgesia.^1,2

Clinical Conundrum

There are many locations to block the brachial plexus as it emerges from the cervical column and then travels down the neck, underneath the clavicle, and into the arm. In our 10-year ED-clinical experience, blocks of the proximal portion of the brachial plexus (superior to the clavicle) offer better analgesia for injuries to proximal structures (ie, shoulder and upper arm), whereas blocks of the distal portion of the brachial plexus (inferior to the clavicle) offer better analgesia for distal structures (ie, elbow, forearm, wrist, and hand). Unfortunately, when performing brachial plexus blocks above the clavicle, we have noticed inconsistent analgesia for distal radius fractures.

The upper extremity regional blocks that most emergency physicians may be familiar with include the interscalene and supraclavicular blocks.³ However, both of these blocks target the proximal portion of the plexus. They provide excellent analgesia to the shoulder and upper arm, but they commonly fail to provide analgesia adequate for closed reduction of distal radius fractures. Also, when placing anesthetic in locations adjacent to the phrenic nerve, there is concern for ipsilateral diaphragmatic paralysis.

Performing a block in the distal region of the brachial plexus, specifically below the clavicle, maximizes distal upper extremity anesthesia while minimizing phrenic nerve blockade. The classic blocks in this region include the infraclavicular block (ICB) in the chest wall above the axilla and the axillary block (AXB) on the medial aspect of the upper arm at the axilla. Unfortunately, these blocks historically have been difficult to perform for two reasons.

First, when performing a traditional ICB with the patient in the position of comfort (shoulder adducted, elbow flexed, and the fractured wrist resting at their side or on their chest/abdomen), the clavicle forces the operator to enter the skin at a very steep angle, significantly decreasing ultrasound visualization of the needle tip during the procedure and increasing the risk of iatrogenic pneumothorax. Second, in order to bring the brachial plexus out from under the clavicle, these blocks are commonly performed with significant upper extremity manipulation. Directly following an injury, abducting and externally rotating the shoulder is often not possible, limiting the generalizability of these infraclavicular approaches to the brachial plexus.