TOPOGRAPHICAL ANATOMY OF THE HEAD, NECK AND TRUNK for the dissection in 2nd year!!
MUSCLES OF THE HEAD
CRANIOFACIAL MUSCLES
origin from the bones of face
are inserted to the skin !
nerve supply – Facial n.
Epicranius m. – frontal belly, occipital belly (two parts are inserted to the galea aponeurotica)
Muscles of eyelids: Orbicularis oculi
(Levator palpebrae superioris)
Corrugator supercilii
Muscles of the nose: Procerus
Nasalis
Muscles of the mouth: Orbicularis oris
Buccinator
Levator labii superioris alaequae nasi
Zygomaticus major
Levator labii superioris
Zygomaticus minor
Levator anguli oris
Risorius
Depressor anguli oris
Depressor labii inferioris
Mentalis
MASTICATORY MUSCLES
nerve supply – Trigeminal n. (Mandibular br.)
Masseter m.: O: zygomatic arch
I: the angle of mandible – masseteric tuberosity
Temporalis m.: O: tempral fossa
I: coronoid process of mandible
Lateral pterygoid m.: O: lateral plate of pterygoid process
I: the neck of the mandible
Medial pterygoid m.: O: pterygoid fossa
I: the angle of the mandible – internal surface
MUSCLES OF THE NECK
Platysma m.: O: the skin over the clavicle
I: the skin along the body of mandible
N.S.: Facial n.
Sternocleidomastoid m.
F: F and E of head
N.S.: XI. n.
Suprahyoid group of muscles:
Digastricus m.: O: digastric fossa of mandible
I: mastoid notch
anterior belly (N.S. trigeminal n.)
posterior belly (N.S. facial n.)
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Stylohyoid m.
Mylohyoid m.: O: mylohyoid line of mandible (N.S. trigeminal n.)
Geniohyoid m.: O: the spine of the mandible (N.S. hypoglossal ansa)
Infrahyoid group: N.S.: ansa cervicalis = hypoglossal ansa
Sternohyoid m.
Thyrohyoid m.
Sternothyroid m.
Omohyoid m. O: scapula
Scaleni muscles
function: flection of cervical spine, elevation of 1st and 2nd ribs
Nerve supply: cervical spinal nerves
Scalenus anterior
O: C3-C6 vertebrae (trensverse processes)
I: the 1st rib (in front of the groove for the subclavian a.)
Scalenus medius
O: C2-C7 vertebrae (trensverse processes)
I: the 1st rib – (behind the groove for the subclavian a.)
Scalenus posterior
O: C4-C5 vertebrae (trensverse processes)
I: the 2nd rib
Fissura scalenorum – scalenic fissure – the gap between scalenus anterior and medius
Subclavian a. and brachial plexus traverse this space
!! subclavian v. is not contained in the scalenic fissure,
it is located in front of the scalenus anterior
MUSCLES OF THE THORAX
1. Intercostales externi muscles - ventrocaudal direction, absent ventrally (ant.
intercostal membrane)
2. Intercostales interni muscles - dorsocaudal direction, absent dorsally (post.
intercostal membrane)
3. Intercostales intimi – like internal, but inserted internally to the costal groove
N. S. Intercostal nerves
Diaphragm: O: sternal part – sternum - xiphoid process
costal part – lower six ribs
lumbar part – upper lumbar vertebrae
I: central tendon of diaphragm
– shows openings for the inf. v. cava, aorta, oesophagus
F: main muscle of respiration
N.S. Phrenic n. (cervical plexus)
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MUSCLES OF THE ABDOMEN
Muscles form anterolateral abdominal wall
Produce: F, E, and Rotation of trunk
N.S.: intercostal nerves
Obliquus externus abdominis
O: lower 8 ribs
I: iliac crest, pubic crest, linea alba
Inguinal ligament – lower free thickened margin of the aponeurosis of the obliquus externus
abdominis muscle
stretched between the ant. sup. iliac spine and pubic tubercle
Obliquus internus abdominis :
O: inguinal ligament, iliac crest, thoracolumbar fascia
I: linea alba
Transversus abdominis:
O: lower 6 ribs, thoracolumbar fascia, iliac crest, inguinal ligament
I: linea alba
Rectus abdominis m.:
O: xiphoid process, costal cartillages
I: pubic bone
N. S. of the muscles of the abdomen - lower six intercostal nerves
The rectus sheath:
- is formed by the aponeuroses of obliquus ext, int. and transversus abdominis m.
- is composed of anterior and posterior layers above the level of the umbilicus
anterior layer below the level of umbilicus
INGUINAL CANAL
narrow canal in the anterior abdominal wall, immediately above the inguinal ligament
- directed mediocaudally
- traversed by - spermatic cord in male
- round ligament of the uterus in female
and ilioinguinal n.
Walls:
inferior wall: inguinal ligament
ventral wall: aponeurosis of the obliquus externus abdominis m.
superior wall: muscle fibres of obliquus abdominis iternus and transversus abdominis
muscles
dorsal wall: transverse fascia - this is a very thin, weak wall!!
Opens
internally – deep inguinal ring – an aperture in the transverse fascia
inferior epigastric vessels lie near this opening
extenally – superficial inguinal ring – opening in the aponeurosis of obliquus ext. abd. m.
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AORTA – ascending, aortic arch, descending aorta (thoracic, abdominal)
ASCENDING AORTA – coronary arteries
AORTIC ARCH
1. brachiocephalic a. - right common carotid a.
- right subclavian a.
2. left common carotid a.
3. left subclavian a.
COMMON CAROTID ARTERY – external carotid, internal carotid
EXTERNAL CAROTID ARTERY
supplies - the structures on the neck and face,
- the oral and nasal cavities (palate, teeth, tongue, paranasal sinuses)
- superf. structures of the cranium
1. Superior thyroid a. – gives superior laryngeal a.
2. Lingual a.
3. Facial a. - submental a.
- superior and inferior labial a.
- nasal and angular a.
4. Ascending pharyngeal a.
5. Occipital a.
6. Posterior auricular a.
7. Temporal superficial a.
- transverse facial a.
- frontal and parietal branches
8. Maxillary a.
supplies the mandible and lower teeth, the maxilla and upper teeth, the nasal cavity and
paranasal sinuses,the masticatory muscles, middle meningeal a.
- infraorbital a., mental a.
INTERNAL CAROTID ARTERY
Supplies the brain and some organs of senses
VEINS OF THE HEAD AND NECK
External jugular v. - opens into the internal jugular v.
receives tributaries: occipital and posterior auricular veins
Internal jugular vein opens into the brachiocephalic v.
receives tributaries:
- sinus of dura mater (draining brain and organs of senses)
- superior thyroid v.
- lingual v.
- facial v.
- pharyngeal v.
- retromandibular v.
maxillary vein (pterygoid plexus) and temporal superficial v.
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SUBCLAVIAN ARTERY
1. Vertebral a. (brain)
2. Internal thoracic (mammary) a. supplies anterior thoracic and abdominal walls, anterior
mediastinum and diaphragm
- Mediastinal br., Pericardial br.
- Anterior intercostal br. – perforating branches
- Musculophrenic a.
terminates as Superior epigastric a.
3. Thyreocervical trunk supplies organs and muscles of neck and back
- Inferior thyroid a. (gives laryngeal and pharyngeal branches)
- Ascending cervical
- Superficial cervical a.
4. Costocervical trunk supplies the skin and the muscles on the neck and the back
- Deep cervical a.
- Dorsal scapular a.
- Superior intercostal a.
accompanying veins open into the brachiocephalic vein!!
SUBCLAVIAN VEIN
except axillary vein receives no important tributaries from the neck
Most the veins accompanying branches of subclavian artery empty into the brachiocephalic
vein
BRACHIOCEPHALIC VEIN
Subclavian and Internal jugular veins join to form brachiocephalic v.
tributaries:
- Vertebral v.
- Internal thoracic v.
- Inferior thyroid v.
THORACIC AORTA
Supplies thoracic walls and organs (except ant. wall and heart)
- Intercostal arteries
- Superior phrenic arteries
- Oesophageal branches
- Bronchial arteries
blood is drained into the Azygos and Hemiazygos veins. Hemiazygos v. opens into the
Azygos v. and this terminates in the Superior vena cava.
SUPERIOR VENA CAVA
arises by union of brachiocephalic veins
azygos vein opens into the Sup. v. cava
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ABDOMINAL AORTA
branches for the abdominal walls:
- Inferior phrenic arteries
- Lumbar arteries
branches for abdominal organs
- Suprerenal arteries
- Renal arteries
- Gonadal arteries – testicular/ovarian
- Coeliac artery - splenic
- left gastric
- common hepatic
- Superior mesenteric a. - supplies small intestine and large intestine – coecum, ascending
and transverse colon near to the left colic flexure
- Inferior mesenteric a. - supplies large intestine – left colic flexure, descending and
sigomod colon, upper part of rectum – superior rectal a.
the blood from the abdominal wall and organs is drained into the Inferior vena cava
INFERIOR VENA CAVA
receives tributaries:
- Lumbar and Phrenic veins (from the walls)
- Suprarenal
- Renal and
- Testicular/Ovarian veins (from the paired organs)
- Hepatal veins – empty the blood from the liver ( which is carried into the liver by portal
vein draining the blood from the spleen and digestive abdominal organs via
splenic v., gastric, superior and inferior mesenteric veins)
COMMON ILIAC A.
EXTERNAL ILIAC A.
- Inferior epigastric a.
INTERNAL ILIAC A.
supplies the walls and the organs of the pelvis
- Superior gluteal a.
- Inferior gluteal a.
- Obturator a.
- Superior and Inferior vesical arteries
- Middle rectal a.
- Uterine a./A. of defferent duct
- Internal pudendal a. – gives: inferior rectal a. and branches for supply of external genital
organs
Blood from the pelvic walls and organs is drained into the accompanying veins
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CERVICAL PLEXUS
arises by union of ventral branches of C1 – C4 spinal nerves
sensory nerves
1. Lesser occipital n.
2. Greater auricular n. – anterior and posterior branches
3. Transverse n. of neck
4. Supraclavicular nerves – medial, intermediate and lateral groups (upper part of thorax)
motor nerves
5. Phrenic n. (diaphragm)
6. Inferior root of the ansa cervicalis (nerve supply of infrahyoid muscles)
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REGIONS OF THE HEAD
CRANIUM:
frontal region
parietal region
temporal region
occipital region
FACE:
nasal
oral
mental
orbital
infraorbital and zygomatic
buccal (here - parotideomasseteric)
REGIONS OF THE NECK
Boundaries: cranially – mandible…mastoid process…external occipital protuberance
caudally – jugular notch…clavicle…acromion…7th cervical vertebra spine
ANTERIOR NECK REGION - between sternocleidomastoid muscles
submental triangle
digastric (submandibular) triangle
carotid triangle
laryngeal region
STERNOCLEIDOMASTOID REGION
LATERAL NECK REGION between sternocleidomastoid m. and trapezius m.
omoclavicular triangle = greater supraclavicular fossa
suprascapular region
POSTERIOR NECK REGION overlying trapezii muscles
REGIONS OF THE THORAX:
presternal reg.
infraclavicular reg. and clavipectoral triangle
pectoral reg. – mammary and inframammary reg.
axillary reg.
REGIONS OF THE ABDOMEN
epigastric and right/lerft hypochondriac regions
umbilical and right/left lateral abdominal regions
pubic and right/left inguinal regions
REGIONS OF THE BACK
vertebral and sacral regions
scapular and infrascapular regions
lumbar regions
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CRANIUM AND FACE
Frontal region
- supratrochlear vessels and nerve (ophthalmic a. [I.C.A], ophthalmic n. [trigeminal])
- supraorbital vessels and nerve (ophthalmic a., ophthalmic n.)
- frontal branch of superficial temporal vessels
Temporal region
- temporal superficial vessels and their parietal branches
- auriculotemporal n. (sensory branch of trigeminal/mandibular)
- temporal branches of facial n. (motor)
- middle and deep temporal vessels (branches from the maxillary a.)
- deep temporal n. (motor branch of trigeminal/mandibular)
Buccal region – parotideomasseteric
- parotid gland and parotid duct
- transverse facial vessels
- facial n. – temporal br.
- zygomatic br.
- buccal br.
- marginal of mandible br.
- temporal superficial a. and v.
- auriculotemporal n.
- on deep surface of parotid gland - retromandibular v.
- external carotid a.
- internal jugular v.
- greater auricular n. – anterior branch
Nasal, oral and infraorbital regions
- facial a. and v. and their branches
- inferior labial
- superior labial
- lateral nasal
- angular
- infraorbital a., v., n. (branches of maxillary a., v., n.)
Mental region
- mental a., v. and n. (sensory branch of trigeminal/mandibular)
THE NECK
SUPERFICIAL STRUCTURES
- external jugular v.
- anterior jugular v.
- lesser occipital n.
- greater auricular n.
- transverse n. of the neck
- supraclavicular nerves – medial, intermediate, lateral
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DEEP STRUCTURES
Carotid triangle:
borders: sternocleidomastoid m.
omohyoid m. – superior belly
digastricus m. – posterior belly
content:
- common carotid a.
- external carotid a. (and its branches – sup. thyroid, facial, lingual)
- internal carotid a.
- internal jugular v. (and its tributaries . sup. thyroid, facial, lingual)
- vagus n.
- hypoglossal n.
- hypoglossal ansa (superior and inferior roots)
- cervical sympathetic trunk
- deep lymph. nodes of the neck
Digastric triangle – submandibular triangle
borders: mandible
digastricus and stylohyoid muscles
content:
- submandibular gland
- facial v.
- facial a. (deeply than vein)
- hypoglossal n.
- submandibular lymph nodes
Laryngeal region
- thyroid gland
- superior thyroid a. and v.
- inferior thyroid a. and v.
Lateral neck region
- subclavian a. and v.
- superficial cervical a. and v.
- transverse cervical a. and v.
- brachial plexus
- accessory n.
THORAX
anterior and lateral thoracic regions
superficial structures: – vessels and nerves for supplying the skin and subcutaneous tissues
- supraclavicular nerves
- anterior cutaneous branches of intercostal vessels and nerves, and their mammary branches
- lateral cutaneous branches of intercostal vessels and nerves
- perforating rami of internal thoracic vessels, and their mammary branches
- mammary gland
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deep structures:
- muscles – pectoralis major and minor, serratus anterior, intercostal muscles
- thoracoepigastric vein
- lateral thoracic a. and v.
- long thoracic n.
- internal thoracic a. and v.
- intercostal arteries, veins and nerves
ABDOMEN
superficial structures
- thoracoepigastric vein
- superficial epigastric vessels
- circumflex ilium superficial vessels
- anterior and lateral cutaneous branches of intercostal vessels and nerves
deep structures
muscles: rectus abdominis m. and its sheath
superior and inferior epigastric vessels on its inner surface
obliquus externus abdominis m.
obliquus internus abdominis m.
transversus abdominis m.
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