Nuchal lines

Nuchal lines
	Occipital bone. Outer surface.
	Side view of head, showing surface relations of bones. (Superior and median lines visible at bottom right.)
Details
Latin	Linea nuchae
Identifiers
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TH	{{#property:P1694}}
TE	{{#property:P1693}}
FMA	{{#property:P1402}}
	Anatomical terms of bone [[[d:Lua error in Module:Wikidata at line 863: attempt to index field 'wikibase' (a nil value).\|edit on Wikidata]]]

The nuchal lines are four curved lines on the external surface of the occipital bone:

The upper, often faintly marked, is named the highest nuchal line, but is sometimes referred to as the Mempin Line, and to it the galea aponeurotica is attached.
Below the highest nuchal line is the superior nuchal line. To it is attached the Occipitalis muscle, the Splenius capitis muscle, the trapezius muscle, and the Sternocleidomastoid muscle.
From the external occipital protuberance a ridge or crest, the median nuchal line, often faintly marked, descends to the foramen magnum, and affords attachment to the ligamentum nuchæ.
Running from the middle of this line is the inferior nuchal line. Attached are the Obliquus capitis superior muscle, Rectus capitis posterior major muscle, and Rectus capitis posterior minor muscle.

Additional images

Posterior view of superior nuchal line (labeled in red) and muscles connecting to it.
Gray187.png

Base of skull. Inferior surface.

This article incorporates text in the public domain from the 20th edition of Gray's Anatomy (1918)