Which nerve injury can occur with high clavicle injuries?

• A. Phrenic nerve
• B. Axillary nerve
• C. Median nerve
• D. Ulnar nerve

Answer: (A)

High clavicle injuries happen near the thoracic inlet, where several structures course close to the medial clavicle. The phrenic nerve runs on the surface of the anterior scalene and travels down into the chest, making it particularly vulnerable when the medial clavicle or the thoracic inlet is disrupted. Injury to this nerve can cause ipsilateral diaphragmatic paralysis, leading to dyspnea that may be most evident with increased effort or in a supine position. This proximity to the fracture site is why the phrenic nerve is the most likely nerve injury in high clavicle injuries.

The other nerves mentioned are less likely in this context: the axillary nerve is typically at risk with injuries near the shoulder joint itself (such as a fracture of the surgical neck of the humerus) and travels laterally with the posterior humeral circumflex artery; the median and ulnar nerves run more distally in the arm and forearm and are not as closely associated with the medial clavicle region.