Semispinalis Capitis
Original Editor - Scott Buxton
Lead Editors - Venus Pagare, Scott Buxton and Kim Jackson
Contents
Description
The posterior muscles of the neck are divided into four layers. The semispinalis capitis and cervicis muscles lie within the third layer[1]. The semispinalis capitis is a long slender muscle which provided a long moment arm to provide efficient extension.
Origin
The muscle originates on the articular processes of the C 5, 6, 7 and 8 as well as the transverse processes of T 1, 2 ,3 ,4 ,5 and 6.
Insertion
The semispinalis capitis attaches onto the occiput inbetween the superior and inferior nuchal line.
Nerve Supply
Greater occipital nerve, which additionally innervates the scalp[2].
Blood Supply
Descending branches of the occipital artery and the superior intercostal artery, via the dorsal rami of the upper two posterior intercostal arteries [3]
Action
- Acting bilaterally : Extension of the head and neck.
- Acting unilaterally : Rotation of head and neck to opposite side
Function
During bilateral contraction this muscle is considered as a prime mover for dynamically maintaining the cervical lordosis[4]. It is also considered as one of the main factors in maintaining the balance of the head on the neck[5]References
- ↑ Rezasoltani. A. Kallinen. M . Mälkiä. M. Vihko. V. Neck semispinalis capitis muscle size in sitting and prone positions measured by real-timefckLRultrasonography. Clinical Rehabilitation 1998; 12: 36–44.
- ↑ Natsis K, Baraliakos X, Appell HJ, Tsikaras P, Gigis I, Koebke J. The course of the greater occipital nerve in the suboccipital region: a proposal for setting landmarks for local anesthesia in patients with occipital neuralgia. Clinical Anatomy. 2006 May;19(4):332-6.
- ↑ http://thewellnessdigest.com/semispinalis-capitis-bac-muscle-origin-insertion-action-innervation/
- ↑ Porterfield JA, DeRosa C. Mechanical neck pain,fckLRperspective in functional anatomy. Philadelphia: WB Saunders, 1995.
- ↑ Sinclair D. Functional anatomy, fifth edition.fckLRLondon: B.S. Publication, 1975