Accessory phrenic nerve

Last revised by Ciléin Kearns on 20 Apr 2023

Citation, DOI, disclosures and article data

Citation:

Heyworth P, Kearns C, Hacking C, et al. Accessory phrenic nerve. Reference article, Radiopaedia.org (Accessed on 30 Sep 2023) https://doi.org/10.53347/rID-60385

DOI:

https://doi.org/10.53347/rID-60385

Permalink:

https://radiopaedia.org/articles/60385

rID:

60385

Article created:

20 May 2018, Paul Heyworth

Disclosures:

At the time the article was created Paul Heyworth had no recorded disclosures.

View Paul Heyworth's current disclosures

Last revised:

20 Apr 2023, Ciléin Kearns

Disclosures:

At the time the article was last revised Ciléin Kearns had no financial relationships to ineligible companies to disclose.

View Ciléin Kearns's current disclosures

Revisions:

5 times, by 4 contributors - see full revision history and disclosures

Systems:

Musculoskeletal, Chest

Sections:

Anatomy

Tags:

accessory phrenic nerve, phrenic nerve

Synonyms:

Accessory phrenic nerve (APN)

The accessory phrenic nerve is an anatomical variant seen in a little over one third of patients (36%). It most commonly arises from the ansa cervicalis, or slightly less commonly, the subclavian nerve. It is unknown as to how much the accessory phrenic nerve contributes to diaphragmatic function in these individuals.

Gross Anatomy

Origin

The accessory phrenic nerve most commonly arises from the ansa cervicalis (45%) or the subclavian nerve (43%).

Rarely, it has also been seen to arise from the C3, C4 or C5 nerve roots, supraclavicular nerve, spinal accessory nerve, nerve to sternohyoid muscle or hypoglossal nerve.

Course

The accessory phrenic nerve most commonly joins with the phrenic nerve within the thorax (two-thirds) with the other third being within the neck at various locations.