lesser occipital nerve
{{Short description|Nerve of the head and neck}}
{{Distinguish|Suboccipital nerve}}
{{Infobox nerve
| Name = Lesser occipital nerve
| Latin = nervus occipitalis minor
| Image = Gray1210.png
| Caption = Side of neck, showing chief surface markings. (Lesser occip. nerve labeled at center right.)
| Image2 = Gray805.png
| Caption2 = The nerves of the scalp, face, and side of neck. (Smaller occipital visible below and to the left of the ear.)
| Innervates = Cutaneous innervation of the posterior aspect of the auricle and mastoid region
| BranchFrom = Cervical plexus (C2)
| BranchTo =
}}
The lesser occipital nerve (or small occipital nerve{{Citation |last1=Yu |first1=Megan |title=Anatomy, Head and Neck, Occipital Nerves |date=2023 |url=http://www.ncbi.nlm.nih.gov/books/NBK542213/ |work=StatPearls |access-date=2023-06-22 |place=Treasure Island (FL) |publisher=StatPearls Publishing |pmid=31194370 |last2=Wang |first2=Shu-Min}}) is a cutaneous spinal nerve of the cervical plexus.{{Cite book |last=Sinnatamby |first=Chummy S. |title=Last's Anatomy |publisher= Elsevier Australia|year=2011 |isbn=978-0-7295-3752-0 |edition=12th |pages=334}} It arises from second cervical (spinal) nerve (C2) (along with the greater occipital nerve). It innervates the skin of the back of the upper neck and of the scalp posterior to the ear.
Structure
= Origin =
It arises from the (lateral branch of the ventral ramus) of cervical spinal nerve C2; it (sources differ) receives or may also receive fibres from cervical spinal nerve C3.{{Cite book |last=Standring |first=Susan |url=https://www.worldcat.org/oclc/1201341621 |title=Gray's Anatomy: The Anatomical Basis of Clinical Practice |year=2020 |isbn=978-0-7020-7707-4 |edition=42nd |location=[New York] |oclc=1201341621}}{{Cite book |last=Cesmebasi |first=Alper |chapter-url=https://www.sciencedirect.com/science/article/pii/B9780124103900000329 |title=Nerves and Nerve Injuries |publisher=Academic Press |year=2015 |isbn=978-0-12-410390-0 |volume=1: History, Embryology, Anatomy, Imaging, and Diagnostics |pages=441–449 |language=en |chapter=31 - Anatomy of the Cervical Plexus and Its Branches |doi=10.1016/B978-0-12-410390-0.00032-9}} It originates between the atlas, and axis.
The lesser occipital nerve is one of the four cutaneous branches of the cervical plexus.{{Cite book |last=Rea |first=Paul |title=Essential Clinically Applied Anatomy of the Peripheral Nervous System in the Head and Neck |publisher=Academic Press |year=2016 |isbn=978-0-12-803633-4 |pages=131–183 |language=en |chapter=3 - Neck |doi=10.1016/B978-0-12-803633-4.00003-X |chapter-url=https://www.sciencedirect.com/science/article/pii/B978012803633400003X}}
= Course and relations =
It curves around the accessory nerve (CN XI){{Cite book |last=Sinnatamby |first=Chummy S. |title=Last's Anatomy |publisher= Elsevier Australia|year=2011 |isbn=978-0-7295-3752-0 |edition=12th |pages=334}} to come to course anterior to it. It then curves around and ascends along the posterior border of the sternocleidomastoid muscle; rarely, it may pierce the muscle. Near the cranium, it perforates the deep cervical fascia. It is continued upwards along the scalp posterior to the auricle. It divides into medial and lateral segments between the inion, and intermastoid line.
= Branches =
It has an auricular, a mastoid, and an occipital branch.
Its auricular branch supplies the skin of the upper and back part of the auricula, communicating with the mastoid branch of the great auricular. This branch is occasionally derived from the greater occipital nerve.{{Citation needed|date=December 2022}}
= Distribution =
= Communications =
It communicates with the greater occipital nerve, great auricular nerve, and the auricular branch of the facial nerve.
= Variation =
Clinical significance
Problems with the lesser occipital nerve cause occipital neuralgia. Nerve block is difficult due to variation in the course of the nerve.
Additional images
File:Gray784.png|Dermatome distribution of the trigeminal nerve
References
External links
- {{SUNYAnatomyFigs|25|03|01}}
- http://www.dartmouth.edu/~humananatomy/figures/chapter_47/47-2.HTM
- http://www.dartmouth.edu/~humananatomy/figures/chapter_47/47-6.HTM
{{Cervical plexus}}
{{Portal bar|Anatomy}}
{{Authority control}}