The Thoracic Nerves - Revision history

Prab: CSV import

2025-03-30T00:53:19Z

CSV import

← Older revision		Revision as of 00:53, 30 March 2025
Line 54:		Line 54:
	The '''lateral cutaneous branch''' of the last thoracic nerve is large, and does not divide into an anterior and a posterior branch. It perforates the Obliqui internus and externus, descends over the [[iliac crest]] in front of the lateral cutaneous branch of the [[iliohypogastric]] (Fig. 819), and is distributed to the skin of the front part of the [[gluteal]] region, some of its filaments extending as low as the greater [[trochanter]].		The '''lateral cutaneous branch''' of the last thoracic nerve is large, and does not divide into an anterior and a posterior branch. It perforates the Obliqui internus and externus, descends over the [[iliac crest]] in front of the lateral cutaneous branch of the [[iliohypogastric]] (Fig. 819), and is distributed to the skin of the front part of the [[gluteal]] region, some of its filaments extending as low as the greater [[trochanter]].
	{{grays}}		{{grays}}
			__NOINDEX__
	__NOINDEX__		__NOINDEX__

Prab: CSV import

2025-02-04T06:04:41Z

CSV import

← Older revision		Revision as of 06:04, 4 February 2025
Line 54:		Line 54:
	The '''lateral cutaneous branch''' of the last thoracic nerve is large, and does not divide into an anterior and a posterior branch. It perforates the Obliqui internus and externus, descends over the [[iliac crest]] in front of the lateral cutaneous branch of the [[iliohypogastric]] (Fig. 819), and is distributed to the skin of the front part of the [[gluteal]] region, some of its filaments extending as low as the greater [[trochanter]].		The '''lateral cutaneous branch''' of the last thoracic nerve is large, and does not divide into an anterior and a posterior branch. It perforates the Obliqui internus and externus, descends over the [[iliac crest]] in front of the lateral cutaneous branch of the [[iliohypogastric]] (Fig. 819), and is distributed to the skin of the front part of the [[gluteal]] region, some of its filaments extending as low as the greater [[trochanter]].
	{{grays}}		{{grays}}
			__NOINDEX__

Prab at 16:01, 29 January 2025

2025-01-29T16:01:40Z

← Older revision		Revision as of 16:01, 29 January 2025
Line 15:		Line 15:
	The first intercostal nerve as a rule gives off no lateral cutaneous branch; but sometimes it sends a small branch to communicate with the [[intercostobrachial]]. From the second [[thoracic nerve]] it frequently receives a connecting twig, which ascends over the neck of the second rib.		The first intercostal nerve as a rule gives off no lateral cutaneous branch; but sometimes it sends a small branch to communicate with the [[intercostobrachial]]. From the second [[thoracic nerve]] it frequently receives a connecting twig, which ascends over the neck of the second rib.

			[[File:Gray819.png\|thumb\|FIG. 819– Diagram of the course and branches of a typica intercostal nerve. (''Picture From the Classic Gray's Anatomy'')]]
	~~<center>http~~:~~//www~~.~~wikimd~~.~~org/images/gray/large/image819~~.~~gif </center>~~


	FIG. 819– Diagram of the course and branches of a typica intercostal nerve. (''Picture From the Classic Gray's Anatomy'')		FIG. 819– Diagram of the course and branches of a typica intercostal nerve. (''Picture From the Classic Gray's Anatomy'')
Line 33:		Line 31:

	'''[[posterior]] branches''' run backward, and supply the skin over the scapula and Latissimus dorsi.		'''[[posterior]] branches''' run backward, and supply the skin over the scapula and Latissimus dorsi.
			[[File:Gray820.png\|thumb\|left\|FIG. 820– Cutaneous distribution of thoracic nerves. (Testut.) (''Picture From the Classic Gray's Anatomy'')]]
	~~<center>http~~:~~//www~~.~~wikimd~~.~~org/images/gray/large/image820~~.~~gif </center>~~

	FIG. 820– Cutaneous distribution of thoracic nerves. (Testut.) (''Picture From the Classic Gray's Anatomy'')		FIG. 820– Cutaneous distribution of thoracic nerves. (Testut.) (''Picture From the Classic Gray's Anatomy'')
Line 40:		Line 37:
	The lateral cutaneous branch of the second intercostal nerve does not divide, like the others, into an anterior and a posterior branch; it is named the '''[[intercostobrachial]] nerve''' (Fig. 816). It pierces the [[Intercostalis externus]] and the [[Serratus anterior]], crosses the [[axilla]] to the medial side of the arm, and joins with a filament from the medial brachial cutaneous nerve.		The lateral cutaneous branch of the second intercostal nerve does not divide, like the others, into an anterior and a posterior branch; it is named the '''[[intercostobrachial]] nerve''' (Fig. 816). It pierces the [[Intercostalis externus]] and the [[Serratus anterior]], crosses the [[axilla]] to the medial side of the arm, and joins with a filament from the medial brachial cutaneous nerve.
	It then pierces the [[fascia]], and supplies the skin of the upper half of the medial and posterior part of the arm, communicating with the posterior brachial cutaneous branch of the radial nerve. The size of the intercostobrachial nerve is in inverse proportion to that of the medial [[brachial]] cutaneous nerve. A second intercostobrachial nerve is frequently given off from the lateral cutaneous branch of the third intercostal; it supplies filaments to the [[axilla]] and medial side of the arm.		It then pierces the [[fascia]], and supplies the skin of the upper half of the medial and posterior part of the arm, communicating with the posterior brachial cutaneous branch of the radial nerve. The size of the intercostobrachial nerve is in inverse proportion to that of the medial [[brachial]] cutaneous nerve. A second intercostobrachial nerve is frequently given off from the lateral cutaneous branch of the third intercostal; it supplies filaments to the [[axilla]] and medial side of the arm.
			[[File:Gray821.png\|thumb\|FIG. 821– Intercostal nerves, the superficial muscles having been removed. (Testut). (''Picture From the Classic Gray's Anatomy'')]]
	~~<center>http~~:~~//www~~.~~wikimd~~.~~org/images/gray/large/image821~~.~~gif </center>~~

	FIG. 821– Intercostal nerves, the superficial muscles having been removed. (Testut). (''Picture From the Classic Gray's Anatomy'')		FIG. 821– Intercostal nerves, the superficial muscles having been removed. (Testut). (''Picture From the Classic Gray's Anatomy'')

Prab at 14:34, 29 August 2023

2023-08-29T14:34:45Z

New page

[[Anatomy]] > [[Gray's Anatomy| Gray's Anatomy of the Human Body]] > IX. Neurology > 6c. The Thoracic Nerves

[[Henry Gray]] (1821–1865). Anatomy of the Human Body. 1918.
== '''The Thoracic Nerves''' ==
'''(NN. Thoracales)'''

=== Anterior divisions of the thoracic nerves ===
The '''[[anterior]] divisions of the [[thoracic]] nerves''' (''rami anteriores; ventral divisions'') are twelve in number on either side. Eleven of them are situated between the ribs, and are therefore termed '''[[intercostal]]''' the twelfth lies below the last rib.
Each nerve is connected with the adjoining [[ganglion]] of the sympathetic trunk by a gray and a white [[ramus]] communicans. The intercostal nerves are distributed chiefly to the [[parietes]] of the [[thorax]] and abdomen, and differ from the anterior divisions of the other spinal nerves, in that each pursues an independent course, ''i. e'' there is no [[plexus]] formation.

The first two nerves supply fibers to the upper limb in addition to their [[thoracic branches]]; the next four are limited in their distribution to the parietes of the thorax; the lower five supply the parietes of the thorax and abdomen. The twelfth [[thoracic]] is distributed to the abdominal wall and the skin of the [[Buttocks|buttock]].
=== '''The First Thoracic Nerve''' ===
The anterior division of the first thoracic nerve divides into two branches: one, the larger, leaves the thorax in front of the neck of the first rib, and enters the [[brachial plexus]]; the other and smaller branch, the '''first [[intercostal]] nerve''' runs along the first intercostal space, and ends on the front of the chest as the first anterior [[cutaneous]] branch of the [[thorax]]. Occasionally this anterior cutaneous branch is wanting.

The first intercostal nerve as a rule gives off no lateral cutaneous branch; but sometimes it sends a small branch to communicate with the [[intercostobrachial]]. From the second [[thoracic nerve]] it frequently receives a connecting twig, which ascends over the neck of the second rib.

<center>http://www.wikimd.org/images/gray/large/image819.gif </center>

FIG. 819– Diagram of the course and branches of a typica intercostal nerve. (''Picture From the Classic Gray's Anatomy'')
=== '''The Upper Thoracic Nerves (''nn. intercostales'')''' ===
The [[anterior]] divisions of the second, third, fourth, fifth, and sixth thoracic nerves, and the small branch from the first thoracic, are confined to the parietes of the thorax, and are named '''thoracic intercostal nerves''' They pass forward (Fig. 819) in the [[intercostal]] spaces below the [[intercostal]] vessels.

At the back of the chest they lie between the [[pleura]] and the posterior intercostal membranes, but soon pierce the latter and run between the two planes of Intercostal muscles as far as the middle of the rib. They then enter the substance of the Intercostales interni, and, running amidst their fibers as far as the [[costal cartilages]], they gain the inner surfaces of the muscles and lie between them and the pleura.

Near the [[sternum]], they cross in front of the internal [[mammary artery]] and Transversus thoracis muscle, pierce the Intercostales interni, the anterior intercostal membranes, and [[Pectoralis major]], and supply the [[integument]] of the front of the thorax and over the [[mamma]], forming the anterior cutaneous branches of the [[thorax]]; the branch from the second nerve unites with the anterior [[supraclavicular]] nerves of the [[cervical plexus]].
=== '''Branches''' ===
Numerous slender muscular filaments supply the [[Intercostales]], the [[Subcostales]], the Levatores [[costarum]], the [[Serratus]] posterior superior, and the Transversus thoracis. At the front of the thorax some of these branches cross the costal cartilages from one intercostal space to another.

'''Lateral cutaneous branches''' (''rami cutanei laterales'') are derived from the intercostal nerves, about midway between the [[vertebrae]] and [[sternum]]; they pierce the Intercostales externi and [[Serratus anterior]], and divide into anterior and posterior branches.
The '''[[anterior]] branches''' run forward to the side and the forepart of the chest, supplying the skin and the [[mamma]]; those of the fifth and sixth nerves supply the upper digitations of the Obliquus externus abdominis. The

'''[[posterior]] branches''' run backward, and supply the skin over the scapula and Latissimus dorsi.

<center>http://www.wikimd.org/images/gray/large/image820.gif </center>

FIG. 820– Cutaneous distribution of thoracic nerves. (Testut.) (''Picture From the Classic Gray's Anatomy'')

The lateral cutaneous branch of the second intercostal nerve does not divide, like the others, into an anterior and a posterior branch; it is named the '''[[intercostobrachial]] nerve''' (Fig. 816). It pierces the [[Intercostalis externus]] and the [[Serratus anterior]], crosses the [[axilla]] to the medial side of the arm, and joins with a filament from the medial brachial cutaneous nerve.
It then pierces the [[fascia]], and supplies the skin of the upper half of the medial and posterior part of the arm, communicating with the posterior brachial cutaneous branch of the radial nerve. The size of the intercostobrachial nerve is in inverse proportion to that of the medial [[brachial]] cutaneous nerve. A second intercostobrachial nerve is frequently given off from the lateral cutaneous branch of the third intercostal; it supplies filaments to the [[axilla]] and medial side of the arm.

<center>http://www.wikimd.org/images/gray/large/image821.gif </center>

FIG. 821– Intercostal nerves, the superficial muscles having been removed. (Testut). (''Picture From the Classic Gray's Anatomy'')
=== '''The Lower Thoracic Nerves''' ===
The anterior divisions of the seventh, eighth, ninth, tenth, and eleventh thoracic nerves are continued anteriorly from the intercostal spaces into the [[abdominal wall]]; hence they are named '''thoracicoabdominal intercostal nerves'''
They have the same arrangement as the upper ones as far as the anterior ends of the [[intercostal]] spaces, where they pass behind the [[costal cartilages]], and between the [[Obliquus]] internus and Transversus [[abdominis]], to the sheath of the [[Rectus abdominis]], which they perforate.

They supply the Rectus abdominis and end as the '''anterior cutaneous branches''' of the abdomen; they supply the skin of the front of the abdomen. The lower intercostal nerves supply the Intercostales and abdominal muscles; the last three send branches to the [[Serratus]] posterior inferior.

About the middle of their course they give off '''lateral cutaneous branches''' These pierce the Intercostales externi and the Obliquus externus abdominis, in the same line as the lateral [[cutaneous]] branches of the upper [[Thoracic nerve|thoracic nerves]], and divide into anterior and posterior branches, which are distributed to the skin of the abdomen and back; the anterior branches supply the [[digitations]] of the Obliquus externus abdominis, and extend downward and forward nearly as far as the margin of the Rectus abdominis; the posterior branches pass backward to supply the skin over the [[Latissimus dorsi]].

The anterior division of the '''twelfth thoracic nerve''' is larger than the others; it runs along the lower border of the twelfth rib, often gives a communicating branch to the first [[lumbar nerve]], and passes under the lateral [[lumbocostal]] arch.

It then runs in front of the [[Quadratus]] lumborum, perforates the [[Transversus]], and passes forward between it and the [[Obliquus]] internus to be distributed in the same manner as the lower [[intercostal nerves]]. It communicates with the [[iliohypogastric]] nerve of the [[lumbar plexus]], and gives a branch to the [[Pyramidalis]].

The '''lateral cutaneous branch''' of the last thoracic nerve is large, and does not divide into an anterior and a posterior branch. It perforates the Obliqui internus and externus, descends over the [[iliac crest]] in front of the lateral cutaneous branch of the [[iliohypogastric]] (Fig. 819), and is distributed to the skin of the front part of the [[gluteal]] region, some of its filaments extending as low as the greater [[trochanter]].
{{grays}}