Longissimus
Encyclopedia
The longissimus is the muscle lateral to the semispinalis. It is the longest subdivision of the sacrospinalis that extends forward into the transverse processes of the posterior cervical vertebrae
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In the lumbar region, where it is as yet blended with the Iliocostalis lumborum, some of its fibers are attached to the whole length of the posterior surfaces of the transverse processes and the accessory processes of the lumbar vertebræ, and to the anterior layer of the lumbodorsal fascia.
In the thoracic region it is inserted, by rounded tendons, into the tips of the transverse processes of all the thoracic vertebræ, and by fleshy processes into the lower nine or ten ribs between their tubercles and angles.
from the second to the sixth inclusive.
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It arises by tendons from the transverse processes of the upper four or five thoracic vertebræ, and the articular processes
of the lower three or four cervical vertebrae, and is inserted into the posterior margin of the mastoid process
, beneath the Splenius capitis and Sternocleidomastoideus.
It is almost always crossed by a tendinous intersection near its insertion.
Cervical vertebrae
In vertebrates, cervical vertebrae are those vertebrae immediately inferior to the skull.Thoracic vertebrae in all mammalian species are defined as those vertebrae that also carry a pair of ribs, and lie caudal to the cervical vertebrae. Further caudally follow the lumbar vertebrae, which also...
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Longissimus thoracis
The Longissimus thoracis is the intermediate and largest of the continuations of the Sacrospinalis.In the lumbar region, where it is as yet blended with the Iliocostalis lumborum, some of its fibers are attached to the whole length of the posterior surfaces of the transverse processes and the accessory processes of the lumbar vertebræ, and to the anterior layer of the lumbodorsal fascia.
In the thoracic region it is inserted, by rounded tendons, into the tips of the transverse processes of all the thoracic vertebræ, and by fleshy processes into the lower nine or ten ribs between their tubercles and angles.
Longissimus cervicis
The Longissimus cervicis (Transversalis cervicis), situated medial to the Longissimus dorsi, arises by long thin tendons from the summits of the transverse processes of the upper four or five thoracic vertebræ, and is inserted by similar tendons into the posterior tubercles of the transverse processes of the cervical vertebraeCervical vertebrae
In vertebrates, cervical vertebrae are those vertebrae immediately inferior to the skull.Thoracic vertebrae in all mammalian species are defined as those vertebrae that also carry a pair of ribs, and lie caudal to the cervical vertebrae. Further caudally follow the lumbar vertebrae, which also...
from the second to the sixth inclusive.
Longissimus capitis
The Longissimus capitis (Trachelomastoid muscle) lies medial to the Longissimus cervicis, between it and the Semispinalis capitisSemispinalis capitis
The Semispinalis capitis is situated at the upper and back part of the neck, deep to the Splenius, and medial to the Longissimus cervicis and capitis....
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It arises by tendons from the transverse processes of the upper four or five thoracic vertebræ, and the articular processes
Articular processes
The articular processes or zygapophyses of a vertebra, two superior and two inferior, spring from the junctions of the pedicles and laminæ...
of the lower three or four cervical vertebrae, and is inserted into the posterior margin of the mastoid process
Mastoid process
The mastoid process is a conical prominence projecting from the undersurface of the mastoid portion of the temporal bone. It is located just behind the external acoustic meatus, and lateral to the styloid process...
, beneath the Splenius capitis and Sternocleidomastoideus.
It is almost always crossed by a tendinous intersection near its insertion.
