For medical undergraduates

1. SUBCLAVIAN ARTERY
AND VEIN
DR. SUNDIP CHARMODE
ASSOCIATE PROFESSOR
DEPARTMENT OF ANATOMY
AIIMS RAJKOT

2. INTRODUCTION
• Right and left subclavian arteries carry blood to the upper limbs
• The territorial supply extends as far as the forebrain, abdominal and
the fingers.

4. ORIGIN
• Right subclavian artery originates
from brachiocephalic trunk.
• It is developed from three sources:
1. Right fourth arch
2. Part of right dorsal aorta
3. Right seventh intersegmental
artery

5. ORIGIN
• Left subclavian artery originates
from the arch of aorta therefore it
possesses thoracic in addition to
cervical part.
• It is developed from seventh
intersegmental artery.

7. COURSE
• The cervical part of each artery undergoes a curved course with
upward convexity and extends from the sternoclavicular joint to the
outer border of the first rib.
• Thereafter it enters through the apex of the axilla and is continued as
the axillary artery.
• Each artery arches over the cervical pleura and the apex of the lung
and is subdivided into in to three parts.

9. COURSE
• Each artery arches over the cervical pleura and the apex of the lung
and is subdivided into in to three parts by the scalenus anterior muscle.
• First part: extend up to the medial border of the muscle
• Second part: behind the muscle
• Third part: lateral border of muscle to outer border of the first rib

11. RELATIONS OF FIRST PART
• In front:
1. SCM, Sternohyoid, Sternothyroid, anterior jugular vein superficial to
infra hyoid muscles
2. Carotid sheath with CCA, Internal jugular vein, and Vagus nerve
3. Cardiac branches of vagus and sympathetic trunk, Ansa cervicalis
and
4. Phrenic nerve and thoracic duct (on left side).

12. RELATIONS OF FIRST PART
• Behind:
1. Apex of lung, covered by cervical pleura and supra-pleural
membrane
2. Sympathetic trunk, and inferior cervical ganglion,
3. Right recurrent laryngeal nerve (on right side) which hooks the
under surface of right subclavian artery.

13. RELATIONS OF SECOND PART
• In front:
1. Scalenus anterior, SCM
2. Subclavian vein below and in front of artery, separated by scalenus
anterior
3. Phrenic nerve on right side only, separated by scalenus anterior.

14. RELATIONS OF SECOND PART
• Behind:
1. Apex of lung, covered by cervical pleura and supra-pleural
membrane
2. Lower trunk of brachial plexus and scalenus medius muscle

15. RELATIONS OF THIRD PART
• In front:
1. Subclavian and external jugular veins
2. Clavicle in the lower part
• Behind:
1. Lower trunk of brachial plexus and scalenus medius muscle

16. BRANCHES
 From first part:
1. Vertebral
2. Internal thoracic
3. Thyro-cervical
4. Costo-cervical
trunk (on left
side)
 From second part:
1. Costo-
cervical trunk
(on right side)
 From third part:
1. Dorsal
scapular
artery

19. VERTEBRALARTERY
• It arises from the upper surface of
first part of SCA.
• Pass upward and through the
foramina transversarium of upper
six cervical vertebra.
• Winds backward, around lateral
mass of atlas.

20. VERTEBRALARTERY
• Enters the cranial cavity through
foramen magnum and at lower border
of pons it unites with similar artery of
opposite side to become Basilar
artery.
• Four parts: First (cervical), Second
(vertebral), third (sub-occipital) and
fourth (intracranial part)

22. VERTEBRALARTERY- FIRST PART
• It extend upward and
somewhat backward from its
origin to foramen
transversarium of 7th vertebra.
• It passes through a triangular
space between longus colli and
scalenus anterior muscle.
(Scaleno-vertebral trigone)

23. VERTEBRALARTERY- FIRST PART
• Relations
• In front:
1. Common carotid artery and vertebral vein
2. Crossed by loop of inferior thyroid artery and thoracic duct
(terminal part)
• Behind:
• Transverse process of C7 vertebra
• Ventral rami of C7 and C8 nerves
• Inferior cervical sympathetic ganglia and stellate ganglia

24. VERTEBRALARTERY- SECOND
PART
• Extends from foramina transversaria of C6 to
C1 vertebrae and is surrounded by plexus of
sympathetic nerves and vertebral veins.
• Up to transverse process of C1, the artery pass
vertically upward and is crossed by ventral rami
of corresponding cervical nerves.

25. VERTEBRALARTERY- SECOND
PART
• From foramen transversarium of axis to atlas,
the artery pass up and laterally to make a
convex outward loop which allows free
movement of cranio-vertebral and
intervertebral joints without any compression
of the artery.

26. VERTEBRALARTERY- THIRD PART
• After emerging from foramen
transversarium of atlas, the third part
winds back around lateral mass of atlas
and appears in the occipital triangle.
• Here, it lodges in suboccipital triangle.
• It lodges in a groove on upper surface of
posterior arch of atlas and dorsal ramus
of C1 nerve intervenes between the arch
and the 3rd part.

29. VERTEBRALARTERY- THIRD PART
• The ventral ramus of C1 nerve run forward medial to 3rd part of artery.
• In suboccipital triangle, the artery is overlapped by semispinalis capitis.
• Finally, artery enters the vertebral canal below the arched border of posterior atlanto-
occipital membrane and continues as 4th part.
• The loop of 3rd part may dampen down the arterial pulsations within the cranial cavity.

30. VERTEBRALARTERY-
FOURTH PART
• The artery pierces the dura and
arachnoid matter and pass upward and
medially through foramen magnum in
front of first tooth of ligamentum
denticulatum.
• In cranial cavity it lies in front of roots of
hypoglossal nerve and medulla
oblongata.

31. VERTEBRALARTERY-
FOURTH PART
• At lower border of pons, it meets with
the fellow of opposite side and forms
the basilar artery.

32. BRANCHES
• In the neck:
1. Spinal branches
2. Muscular branches

33. BRANCHES
• In the cranial cavity:
1. Meningeal branches
2. Posterior spinal artery
3. Anterior spinal artery
4. Posterior inferior cerebellar artery

34. CLINICAL CORRELATES
1. Medial medullary syndrome- Lesion of anterior spinal artery-
impairment of volitional movements on contralateral side of body –
cortico-spinal tract is involved
2. Lateral medullary syndrome: thrombosis of PICA – loss of pain and
thermal senses on same side of face and opposite half of body. There is
paralysis of vocal cord, soft palate and pharyngeal muscles on same side
of body.
3. Subclavian steal syndrome: obstruction to SCA proximal to the origin pf
vertebral artery. Ischemic neurological symptoms.

35. INTERNAL THORACIC ARTERY

36. INTERNAL THORACIC ARTERY

37. INTERNAL THORACIC ARTERY
• It arises from the inferior surface of first
part of subclavian artery opposite the
origin of thyrocervical trunk and about 2
cm above the sternal end of clavicle.
• It passes downwards and medially in front
of cupola of pleura and under cover of IJV
and SC Veins.

38. INTERNAL THORACIC ARTERY
• The artery enters the thorax behind the
sterno-clavicular joint and is crossed in front
of phrenic nerve from lateral to medial side.
• In the thorax, it passes downward about 1.25
cm from the lateral border of sternum and at
the level of the sixth intercostal space
divided into Musculo-phrenic and Superior
Epigastric arteries.

40. INTERNAL THORACIC ARTERY - BRANCHES
1. Peri-cardio-phrenic artery: It accompanies the phrenic nerve.
2. Mediastinal branches: supplies contents of the anterior abdominal wall
and the thymus gland.
3. Pericardial branches: supply the anterior part of pericardium
4. Sternal branches: supply sternum and sterno-costalis muscles
5. Anterior intercostal arteries: they are confined to upper six intercostal
spaces. In each space, 2 arteries - upper anterior anastomose with
corresponding posterior I-C artery and the lower one will anastomose
with its collateral branch.

41. INTERNAL THORACIC ARTERY - BRANCHES
6. Perforating arteries: They pierce the intercostal spaces. Those of
2nd , 3rd and 4th spaces supply the mammary gland.
7. Musculo-phrenic artery runs obliquely behind 7th, 8th and 9th costal
cartilages and pierce diaphragm. Along its course, it provides two
anterior I-C arteries to each of 7th, 8th and 9th intercostal spaces.
8. Superior epigastric artery: Enters rectus sheath. Within the sheath,
it anastomoses with inferior epigastric artery.

49. CLINICAL CORRELATES
• In Coarctation of Aorta, the anastomosis between superior and inferior
epigastric arteries is significantly dilated to maintain collateral
circulation.
• In Aortic Coronary Bypass operation, ITA is used as a vascular graft to
negotiate with peripheral patent portion of occluded coronary artery.

50. THYROCERVICAL TRUNK
• It arises from upper surface of the first part of SCA, just distal to the
origin of vertebral artery.
• The arterial trunk divides almost at once into three branches:
1. Inferior Thyroid artery
2. Superficial cervical artery and
3. Suprascapular artery

51. INFERIOR THYROID ARTERY

52. INFERIOR THYROID ARTERY
• Ascends in front of medial border of scalenus anterior muscle and then
arches medially at the level of C7 vertebra between the vertebral vessels
behind and carotid sheath with contents in front.
• The sympathetic trunk and the middle cervical ganglion usually lie in front
of the loop of the artery.
• On left side, close to origin, artery is crossed by thoracic duct.
• Close to the lower pole of thyroid gland, artery lies in relation with
recurrent laryngeal nerve.

54. INFERIOR THYROID ARTERY
• On reaching lower pole of thyroid gland,
artery gives ascending and descending
branches - supplies posterior and inferior
parts of thyroid gland.
• The Ascending branch anastomose with
superior thyroid artery and supply
parathyroid glands.
•

55. INFERIOR THYROID ARTERY - BRANCHES
1. Ascending Cervical artery: Ascends along
the transverse process of cervical vertebrae
along the medial side of the phrenic nerve and
supplies the vertebrae and the spinal cord.
2. Inferior Laryngeal artery: It accompanies the
recurrent laryngeal nerve and supplies the
laryngeal muscles and its mucous membrane
below the vocal folds.
3. Tracheal, Esophageal, and Pharyngeal
branches: supply respective structures.

56. SUPERFICIAL CERVICAL
ARTERY
• It passes laterally and upward in
front of the phrenic nerve, scalenus
anterior and appears in the posterior
triangle in front of the trunks of
brachial plexus and levator scapulae.
• The artery ascends beneath the
trapezius and anastomoses with
superficial division of descending
branch of occipital artery.

57. SUPRASCAPULAR ARTERY
• Lies below the superficial cervical artery,
and passes laterally across the phrenic
nerve, scalenus anterior and in front of 3rd
part of SCA and cords of brachial plexus.
• The artery runs behind the clavicle,
subclavius and inferior belly of omohyoid
and appears in the supraspinous fossa.
• Forms scapular plexus by anastomosing
with circumflex scapular and dorsal
scapular arteries.

59. COSTO-CERVICAL ARTERY
• It arises from the back of first part of subclavian
artery on the left side or second part of the same
artery on the right side.
• The artery arches backward above the cupola of
the pleura and on reaching the neck of the first
rib it divides into Deep Cervical and Superior
Intercostal arteries.
• Deep cervical artery: It passes backward above
the C8 nerve between the neck of first rib and
transverse process of C7 vertebra.

60. COSTO-CERVICAL ARTERY
• It then ascends between semispinalis
capitis and semispinalis cervicis and
anastomoses with the deep division of the
descending branch of occipital artery.
• Superior Intercostal artery: It descends
in front of neck of the upper ribs and
provides posterior intercostal arteries for
the first two intercostal spaces.

62. DORSAL SCAPULAR ARTERY
• It usually arises from the third part of subclavian
artery and passes laterally between the upper and
middle trunks, or middle and lower trunks of
brachial plexus.
• It then passes deep to levator scapulae and
descends along the medial border of scapula
deep to rhomboids, accompanied by dorsal
scapular nerve.

63. DORSAL SCAPULAR
ARTERY
• The artery supplies the
rhomboids and enters in the
formation of scapular
anastomoses.

64. DEEP VEINS OF NECK
• Subclavian and Internal Jugular veins
• Subclavian vein – upper extremity
• Internal jugular vein – brain, superficial part of face and neck.

65. SUBCLAVIAN VEIN
• It is the continuation of axillary vein
and extends from outer border of first
rib to medial border of scalenus
anterior muscle, where it joins with
internal jugular vein to form
brachiocephalic vein.
• The arching of SCV is at lower level
than SCA.
• About 2 cm from its termination the
vein is provided with a pair of valves.

66. SUBCLAVIAN VEIN - RELATIONS
• In front: clavicle and
subclavius muscle
• Behind: SCA separated
by the scalenus anterior
and phrenic nerve
• Below: first rib and cupola
of pleura

67. SUBCLAVIAN VEIN - TRIBUTARIES
1. External jugular vein
2. Dorsal scapular vein
3. Occasionally, anterior jugular vein
4. Occasionally, small vessels from cephalic vein
5. At the junction between SCV and IJV – termination of thoracic duct
on left side and Right lymphatic duct on other side.

68. THANK YOU