The clavicle is one of the most commonly fractured bones in the human body. Every  year, approximately 332,000 people in the United States suffer from a clavicular fracture.^1,2 In the emergency department (ED), the focus of treatment is pain control and immobilization unless there is a clear indication for surgery, such as open fractures, skin tenting, or neurovascular compromise.^1,2 The mainstay of pain control in the ED has been either oral or intravenous non-steroidal anti-inflammatory drugs (NSAIDs) or opioids.² However, in our experience these agents commonly do not offer optimal pain control in the acute setting, leading to repeat dosing and, often, prolonged ED stays.

The ultrasound-guided clavipectoral plane block (CPB) is a newly described technique in the emergency medicine literature.³ The CPB is a simplified technique that can be easily integrated into clinical care by visualizing the deposition of anesthetic in the fascial plane around the clavicle.^3,4 While the CPB was first described in the perioperative setting, it may be even more impactful in the ED setting after an acute injury.^4-6

1. Anatomy

The clavicle is enwrapped by the clavipectoral fascia, which extends inferiorly from the clavicle, deep to the pectoralis major and superficial to the subclavius muscles. The innervation of the clavicle is poorly understood partly due to anatomical variations.⁷ The CPB circumvents this issue by directly blocking the terminal sensory nerve endings that innervate the clavicle.³

2. Ultrasound Survey Scan

FIGURE 1A: Ultrasound probe should be placed at the clavicle with the probe marker facing cephalad (toward the head).

FIGURE 1B: Ultrasound image with labeled relevant anatomy. (Click to enlarge.)

The clinician should note the fracture site (either via palpable landmark or ultrasound visualization). The initial survey scan should be either just lateral or medial to this site.

The anatomy for the CPB is visualized by placing a linear transducer in a cranial-caudal direction at the midclavicular line with the probe marker towards the patient’s head (Figure 1A). In this position, the pectoralis major and subclavius muscle are located just below the clavicle (Figure 1A). The goal of this simple block is to place anesthetic gently under the fascial plane that defines the border of the pectoralis muscle and the clavicle (Figure 2A, 2B). In our experience, placing anesthetic near the top of the clavicle will separate this potential space and allow for optimal fracture analgesia.

FIGURE 2A: Ultrasound probe placed in a sagittal plane with the probe marker cephalad, in-plane needle technique.