Phrenic nerve injury usually accompanies signs and symptoms of which condition?

• A. Torticollis
• B. Brachial plexus avulsion
• C. Erb-Duchenne palsy
• D. Klumpke palsy

Answer: (C)

Phrenic nerve involvement is most classic with injuries to the upper part of the brachial plexus, specifically Erb-Duchenne palsy. The phrenic nerve receives contributions from C3–C5 and travels near the upper plexus roots (C5–C6). When trauma affects these upper roots, nearby structures including the phrenic nerve can be affected, leading diaphragmatic dysfunction and respiratory signs alongside the typical shoulder/arm weakness of Erb-Duchenne palsy. Klumpke palsy involves the lower trunk (C8–T1) and is less likely to impact the phrenic nerve, while torticollis is a neck muscle condition rather than a brachial plexus root injury. Therefore, the presentation that best fits phrenic nerve injury is Erb-Duchenne palsy.