Anatomy Super Supplement

Head and Neck Loubomir E. Antonio, M.D. Bones of Skull Cranium Eight (8) Bones Frontal Parietal (2) Occipital Temporal (2) Sphenoid Ethmoid Facial Bones Fourteen (14) bones • Zygomatic(2) • Maxillae (2) • Nasal bones(2) • Lacrimal (2) • Vomer (1) • Palatine (2) • Inferior concha (2) • Mandible (1) New Born Skull Fontanelles

Anterior fontanelle “Bregma” Diamond-shaped

Between

Two halves of frontal bone Two parietal bones Closed by 18 months

Posterior fontanelle “Lambda” Triangular

Between

Two parietal bones Occipital bone

Closed by first year of life CLINICAL SIGNIFICANCE Depressed – Dehydration Bulging – Increased ICP Mastoid Process Not present at birth

Develops during first 2 years of life CLINICAL SIGNIFICANCE

Forceps delivery may result to Facial nerve injury Adult Skull

Sutures

- fibrous type ( synarthroses )

- Wormian or Inca bones in between sutures Coronal Suture • Frontal bone • Parietal bone Sagittal Suture • Parietal bones Lambdoid Suture • Parietal bone • Occipital bone Adult Skull Pterion

Thinnest part of lateral wall Between

Anteroinferior corner of the parietal bone Greater wing of sphenoid

INTRACRANIAL HEMORRHAGES

Epidural – Ant. division middle meningeal artery Subdural – Cerebral veins

Subarachnoid – Aneurysm/Angioma IntraParenchymal – Lenticulostriate artery INTRACRANIAL HEMORRHAGE (INFANT)

Excessive molding

Tears anterior attachments of falx cerebri to tentorium cerebelli Bleeding comes from;

Great Cerebral vein Straight sinus Inferior Sagittal sinus SKULL FRACTURE

Adult

- likened to an eggshell - splintering of bone Young child

- likened to a table tennis ball - “pond fracture”

FRACTURES OF CRANIAL FOSSAE Anterior Cranial Fossa

- Epistaxis - Rhinorrhea -Racoon’s eye - Exophthalmos

Middle Cranial Fossa (WEAKEST) - Otorrhea/Rhinorrhea - Damage to CN 3,4,6 - Damage to CN 7,8 Posterio Cranial Fossa

- Battle’s sign

- Damage to CN 9,10,11 Nasal fractures

- most common

- considered open fractures - damage to mucoperiosteum - septal hematoma

Maxillofacial fractures - facial swelling - diplopia

- malocclussion/ open bite deformities - anesthesia/paresthesia in the cheek or upper gum (infraorbital nerve)

Le Fort Classification of Maxillofacial Fractures

ARTERIAL SUPPLY Anterior Circulation- ICA Posterior Circulation- VA VENOUS DRAINAGE Superior sagittal sinus Inferior sagittal sinus Great vein of Galen Straight sinus Transverse sinus Sigmoid sinus

CLINICAL SIGNIFICANCE Queckenstedt’s Test

(+) FAILURE of the cerebral venous pressure to rise as measured by a lumbar tap in the sub arachnoid space upon compression of the IJV signifies obstruction at the vertebral canal or meninges (tumor)

Cavernous Sinus Contents CNs III, IV, V1,V2

and VI ICA

CLINICAL SIGNIFICANCE

Cavernous Sinus Thrombosis V

infections in the dangerous area of the face V

thrombosis of the facial vein V

organisms ascend through inf. ophthalmic vein CSF PATHWAY Choroid plexus Lateral ventricles foramen of Monroe 3rd _ventricle aqueduct of Sylvius/iter 4th _ventricle foramen of Luschka and Magendie Subarachnoid space Arachnoid granulations Cranial Nerve I – Olfactory Nerve

Olfactory nerve cells -> Olfactory bulb -> Olfactory tract -> Olfactory area

Type: Sensory Function: Smells Lesion: Anosmia Foramen: Cribiform plate Innervated Region:Nasal Cavity Cranial nerve II – Optic Nerve

Retina -> Optic chiasm -> Optic tract -> LGB -> Optic radiation -> Visual cortex

Type: Sensory Function: Vision

Lesion: Visual field deficits (Anopsia) Foramen: Optic canal

Innervated Region: Orbit

Cranial nerve III – Oculomotor Nerve

Anterior midbrain -> Lateral wall Cavernous Sinus -> SOF -> EOM’s except SO and LR

sphincter pupillae Ciliary muscles Type: Motor

Functions:

• EOMs

*adduction most important action (medial rectus) • Constricts pupil (spincter pupillae) • Accomodation (ciliary muscle) • Raises upper eyelid (levator papillae) Lesion: Diplopia, lateral/external strabismus Foramen: Superior oribital fissure

Innervated Region: Orbit

Cranial nerve IV - Trochlear Nerve

Posterior midbrain -> Lateral wall cavernous Sinus -> SOF -> Superior Oblique

Type: Motor Function:

Depresses and abducts eyeball (Superior oblique) Intorts

Lesion:

Weakness looking down with adducted eye Difficulty going down stairs

Head tilts away from lesioned side Foramen: Superior orbital fissure Innervated Region: Orbit

Cranial nerve VI – Abducent Nerve

Between pons/medulla -> Cavernous Sinus w/ICA -> SOF -> Lateral Rectus

Type: Motor

Function: Abducts eyeball (lateral rectus)

Lesion: diplopia, medial/internal strabismus, loss of parallel gaze Foramen: Superior orbital fissure

Innervated Region: Orbit

Cranial Nerve V - Trigeminal Nerve Anterior pons

- small motor root

-large sensory root Trigeminal Ganglion Trigeminal Ganglion ( anterior border )

- arises the 3 divisions Cranial nerve V1-Ophthalmic Nerve

Passes in the lateral wall of Cavernous Sinus -> SOF Nasociliary

Post. Ethmoidal Infratrochlear Long ciliary nerve

Anterior ethmoidal -> External nasal nerve ( tip of nose )

Sensory br. To ciliary ganglion

Frontal – divides into supraorbital/trochlear nerves Lacrimal +

zygomaticotemporal branch of V2 lacrimal

gland

Type: Sensory

Function: General sensation of forehead/scalp/cornea Lesion:

• Loss of sensation in skin of forehead/scalp • Loss of blink reflex w/ CN VII

Innervated Region: Orbit and scalp Cranial nerve V2 – Maxillary Nerve

Foramen rotundum -> pterygopalatine fossa IOF Meningeal branch

Zygomaticotemporal lacrimal gland ( w/ lacrimal nerve of V1 )

Zygomaticofacial

Ganglionic branches – TWO nerves going to pterygopalatine ganglion

Posterior Superior Alveolar Middle Superior Alveolar Anterior Superior Alveolar Type: Sensory

Function: General sensation of palatae, nasal cavity, maxillary face, maxillary teeth

Lesion: Loss of general sensation in skin over maxilla, maxillary teeth Foramen: Foramen rotundum

Innervated Region: Pterygopalatine fossa (leave by openings to face, oral, and nasal cavity)

Cranial nerve V3 – Mandibular Nerve Foramen ovale -> Infratemporal fossa Type: Mixed

Motor: MNEMONIC: My Ass Meets The Toilet Mylohyoid Anterior digastric

Muscles of mastication Tensor veli palatini

Tensor tympani Sensory: MNEMONIC: LIBAG

Lingual nerve Inferior Alveolar Buccal nerve

Auriculotemporal nerve Ganglion ( otic ganglion ) Lesion:

Loss of general sensation in skin over mandible, mandibular teeth, tongue

Weakness in chewing

Jaw deviation toward weak side

Foramen: Foramen Ovale

Innervated Region: Infratemporal fossa INJURY TO THE LINGUAL NERVE COURSE: infratemporal fossa

V

inferior to superior constrictor V

(closely related to last molar tooth)

v

submandibular triangle

In cases of clumsy extraction of impacted 3rd _{molar tooth}

Cranial Nerve VII - Facial Nerve

Type: Mixed Function:

Motor: muscles of facial expression, posterior belly of digastric, stylohyoid, stapedius

Sensory

Taste to anterior two-thirds of tongue/palate Autonomics

Salivates (submandibular, sublingual glands) Tears (lacrimal gland)

Makes mucus (nasal and palatine glands) Lesion:

• Corner of mouth droops, can’t close eye, can’t wrinkle forehead, loss of blink reflex, hyperacusis

• Alteration or loss of taste (ageusia) • Eye dry and red

Foramen: Internal auditory meatus

Innervated Region: Face, nasal and oral cavity, branches leave skill in stylomastoid foramen, petrotympnic fissure, or hiatus of facial canal Cranial nerve VIII – Vestibulocochlear Nerve

Vestibule AND semicircular canal > Vestibular ganglion > Int. acoustic meatus > Brainstem/Cerebellum

Cochlea -> Spiral ganglion -> Internal acoustic meatus -> Auditory Center

Type: Sensory Function: Hears

Linear acceleration (gravity) Angular acceleration (head turning) Lesion: Loss of balance, nystagmus Foramen: Internal auditory meatus Innervated Region: Inner ear

Cranial Nerve IX – Glossopharyngeal Nerve

Type: Mixed Function:

Senses pharynx, carotid sinus/body Salivates (parotid gland)

Tastes (posterior one third of tongue) Motor to one muscle - stylopharyngeus Lesion: Loss of gag reflex with CN X Foramen: Jugular foramen

Innervated Region: Neck/pharynx/tongue Cranial Nerve X – Vagus Nerve

Type: Mixed Function:

Muscles of palate and phaynx for swallowing except tensor veli

palatini (CN V) and stylopharyngeus (CN IX)

To all muscles of larynx (phonates) Sensation to larynx and laryngopharynx Sensation to larynx and GI tract

To GI tract smooth muscle and glands in foregut and midgut Lesion:

Nasal speech. Nasal regurgitation (due to palate weakness) Dysphagia, palate droop

Uvula pointing CONTRALATERAL from affected side Hoarseness/fixed vocal cord

Loss of gag reflex with IX Loss of cough reflex Foramen: Jugular foramen

Innervated Region: Neck/ Pharynx/ Larynx/ Thorax/ Abdomen

Cranial Nerve XI – Spinal Accessory Nerve

Brainstem - 2roots

( Motor and

Sensory- Nervus

intermedius )

Internal acoustic

meatus

Facial canal

Chorda tympani

petrotympanic

fissure

Infratemporal

fossa

Inner Ear/Middle ear

Nerve to

stapedius

joins lingual nerve

Geniculate ganglion

Greater petrosal

nerve

Pterygopalatine

ganglion

Submandibular/

Sublingual gland

Stylomastoid

foramen

Lacrimal/Nasal/Palat

al glands Ant.

2/3 tongue

Posterior auricular

Stylohyoid

Posterior belly of

digastric

Brainstem Jugular

foramen Neck –

POSTERIOR to

STLOPHARYNGEUS

IMPORTANT

BRANCHES

Tympanic branch

lesser petrosal nerve

Otic ganglion w/

Parotid gland

Auriculotemporal

nerve

Carotid branch

Carotid body/sinus

Pharyngeal branch

Pharyngeal plexus

( w/ CN X and SNS )

Lingual branch

Posterior 1/3 of

tongue

Nerve to

stylopharyngeus

Brainstem Jugular

foramen

Neck-within the carotid

sheath

IMPORTANT

BRANCHES

( neck ):

Cardiac branches

Cardiac plexus

Recurrent laryngeal

nerve ALL

Intrinsic muscles of

larynx EXCEPT

CRICOTHYROID

Auricular branches

Tympanic

membrane/Pinna

Meningeal branches

Pharyngeal branch

Pharyngeal

plexus

- supply

ALL muscles of

Pharynx EXCEPT

STYLOPHARYNGEUS

- muscles

of soft palate

EXCEPT TENSOR

VELI PALATINI

Superior laryngeal

nerve

Internal

laryngeal nerve –

SENSORY to larynx

External

laryngeal nerve –

ONLY MOTOR to

CRICOTHYROID

Type: Motor Function:

Turn head to opposite side (Sterocleidomastoid) Elevates and rotates scapula (Trapezius) Lesion:

Weakness turning head to opposite side Shoulder droop

Foramen: Jugular foramen Innervated Region: Neck

Cranial Nerve XII – Hypoglossal Nerve

Brainstem > Hypoglossal canal > Neck down to lower border of

POST.BELLY DIGASTRIC > crosses ext/int. Carotid arteries >

deep to mylohyoid > below lingual nerve and submandibular duct IMPORTANT BRANCHES:

Meningeal branch Descending branch ( C1 )

- joins descending cervical nerve ( C2C3 ) to form ANSA CERVICALIS

to supply STERNOHYOID, OMOHYOID, STERNOTHYROID Nerve to THYROHYOID

Nerve to GENIOHYOID

ALL muscles of the tongue EXCEPT: PALATOGLOSSUS Type: Motor

Function: Moves tongue (styloglossus, hyoglossus, genioglossus, and intrinsics. *palatoglossus by pharyngeal plexus)

Lesion: Tongue pointing IPSILATERAL side of protrusion Foramen: Hypoglossal canal

Innervated Region: Tongue MEMORIZE

All muscles of the tongue are supplied by CN12 EXCEPT: PALATOGLOSSUS ( pharyngeal plexus CN9,10)

All muscles of the palate are supplied by the pharyngeal plexus EXCEPT: TENSOR VELLI PALLATINI

(CNV – 3division) MEMORIZE

All muscles of the pharynx are supplied by the pharyngeal plexus EXCEPT: STYLOPHARYNGEUS

( CN IX )

All intrinsic muscles of the larynx are supplied by the recurrent laryngeal nerve

EXCEPT: CRICOTHYROID (External branch – Superior laryngeal nerve ) Summary of Tongue Innervation Sensation

Anterior 2/3rds

Sensation CN V3 (Trigeminal mandibular) Taste CN VII (Facial)

Posterior 1/3rd Sensation and Taste

Mainly CN IX (Glossopharyngeal), Extreme posterior CN X (Vagus) Motor CN XII (Hypoglossal) Scalp 5 layers “SCALP” Skin

Connective tissue of superficial fascia Aponeurosis

Loose Connective Tissue ( dangerous layer ) Periosteum of skull and bones

ORBIT

Pyramidal in shape Orbital Margin Superior-frontal bone Lateral- frontal and zygomatic Inferior- zygomatic and maxilla Medial-maxilla and frontal EYE TRAUMA

- Least protected from the LATERAL side Blowout Fractures

- explodes INFERIORLY into the Maxillary sinus resulting to diplopia, injury to

infraorbital nerve and entrapment of inferior rectus muscle

LACRIMAL APPARATUS Lacrimal gland Lacrimal punctum Lacrimal canaliculi Lacrimal sac Nasolacrimal duct Inferior nasal concha MIDDLE EAR

Superior wall

tegmen tympani (petrous bone) Anterior wall

thin bone plate /// ICA 2 openings Tensor tympani

Eustachian tube Posterior wall

aditus to mastoid antrum pyramid – stapedius tendon Medial wall

lateral wall/promontory of inner ear 2 windows oval round Lateral wall tympanic membrane(dflat) epitympanic recess Inferior wall

Thin bone plate /// IJV INFECTIONS AND OTITIS MEDIA

- Pathogenic organisms ascending through the pharyngotympanic tube from the nasopharynx COMPLICATIONS

Acute Mastoiditis/Sigmoid sinus Thrombosis - thru the mastoid antrum Meningitis/cerebral abscess

- superiorly

Facial nerve palsy/Labyrinthitis/Vertigo - medially

Osseus membranous labyrinth Sensory organ Vestibule

Semicircular Canal Cochlea

Utricle and Saccule Macula

Semicircular Ducts Crista ampullaris Cochlear Duct organ of Corti

COCHLEA

Scala Vestibuli

Scala Media/cochlear duct

Brainstem - 2roots

( Motor and

Sensory- Nervus

intermedius )

Internal acoustic

meatus

Facial canal

Chorda tympani

petrotympanic

fissure

Infratemporal

fossa

Inner Ear/Middle ear

Nerve to

stapedius

joins lingual nerve

Geniculate ganglion

Greater petrosal

nerve

Pterygopalatine

ganglion

Submandibular/

Sublingual gland

Stylomastoid

foramen

Lacrimal/Nasal/Palat

al glands Ant.

2/3 tongue

Posterior auricular

Stylohyoid

Posterior belly of

digastric

Brainstem Jugular

foramen Neck –

POSTERIOR to

STLOPHARYNGEUS

IMPORTANT

BRANCHES

Tympanic branch

lesser petrosal nerve

Otic ganglion w/

Parotid gland

Auriculotemporal

nerve

Carotid branch

Carotid body/sinus

Pharyngeal branch

Pharyngeal plexus

( w/ CN X and SNS )

Lingual branch

Posterior 1/3 of

tongue

Nerve to

stylopharyngeus

Brainstem Jugular

foramen

Neck-within the carotid

sheath

IMPORTANT

BRANCHES

( neck ):

Cardiac branches

Cardiac plexus

Recurrent laryngeal

nerve ALL

Intrinsic muscles of

larynx EXCEPT

CRICOTHYROID

Auricular branches

Tympanic

membrane/Pinna

Meningeal branches

Pharyngeal branch

Pharyngeal

plexus

- supply

ALL muscles of

Pharynx EXCEPT

STYLOPHARYNGEUS

- muscles

of soft palate

EXCEPT TENSOR

VELI PALATINI

Superior laryngeal

nerve

Internal

laryngeal nerve –

SENSORY to larynx

External

laryngeal nerve –

ONLY MOTOR to

CRICOTHYROID

2 roots

Cranial root – from

brainstem

Jugular foramen

Neck

- SCM

Foramen

magnum

- Trapezius

Spinal root – C1

to C5

Scala Tympani Membranes

Reissner’s

Basilar

NASAL CAVITY Lateral nasal wall

superior turbinate middle turbinate Inferior turbinate Medial nasal wall

septal cartilage

perpendicular plate of ethmoid vomer

MNEMONIC Kiss Little Girls ASS

Kiesselbach’s plexus Little’s Area

Greater Palatine artery Anterior Ethmoidal artery Sphenopalatine artery Superior labial artery PARANASAL SINUSES Sphenoidal sinus Ethmoidal sinus Anterior Middle Posterior Frontal sinus Maxillary sinus DRAINAGE Sphenoethmoidal recess Sphenoidal sinus Superior meatus

Posterior ethmoidal sinus Middle meatus

Frontal sinus

Anterior ethmoidal sinus Middle ethmoidal sinus Maxillary sinus Inferior meatus Nasolacrimal duct Muscles of Facial Expression

Innervated by terminal branches of facial nerve Temporal

Zygomatic Buccal Mandibular Cervical

“Ten Zebras Bit My Cheek” FREY SYNDROME

Post-gustatory sweating due to damage to auriculotemporal and great auricular nerve ( trauma/surgery)

Both fibers may innervate a sweat gland

A stimulus intended for saliva production results to sweat secretion instead

TROUBLESOME BLEEDING AFTER A TOSILLECTOMY

Damage to external palatine vein located just lateral to the tonsills at the tonsillar fossa

ORAL CAVITY LESIONS

QUINCKE’S DISEASE VS QUINSY Quincke’s disease – angioedema of uvula Quinsy – peritonsillar abscess

Muscles of Mastication • Masseter

• Temporalis M – Munching • Medial Pterygoid

• Lateral Pterygoid L - Lowers

Triangles of the Neck Posterior Triangle • Occipital triangle • Supraclavicular triangle Anterior Triangle • Carotid triangle • Digastric triangle • Submental triangle • Muscular triangle Posterior Triangle Boundaries • Trapezius (posterior) • Sternocleidomastoid (anterior) • Clavicle (inferior)

Divided by Omohyoid into • Occipital triangle • Supraclavicular triangle Floor • Anterior scalene • Middle Scalene • Posterior Scalene • Levator scapulae • Splenius Capitis Posterior Triangle Contents

In scalene interval (between anterior & middle scalene) • Three (3) trunks of brachial plexus • Subclavian artery

Spinal accessory nerve (CN XI) to • Sternocleidomastoid • Trapezius

Phrenic nerve (anterior surface of anterior scalene) Cutaneous branches of cervical plexus

• greater auricular, • lesser occipital, • transverse cervical, • supraclavicular nerves Anterior Triangle Boundaries

Anterior border of sternocleidomastoid Anterior midline Body of mandible Subtriangles Digastric triangle Submental triangle Muscular triangle Carotid triangle Digastric Triangle Boundaries

• Lower border of mandible • Posterior belly of digastric • Anterior belly of digastric Contents

• Submandibular gland • Submandibular duct • Submandibular lymph node • CN XII

• Cervical mandibular branch of CN VII • Submental branch of facial vessels Submental Triangle

Boundaries Mentum of mandible

Anterior bellies of digastric muscles Hyoid bone

Floor: Mylohyoid

Apex: Mandibular symphysis Contents

Submental lymph nodes Muscular Triangle Boundaries

• Midline of neck

• Superior belly of omohyoid

• Anterior border of sternocleidomastoid Roof: Strap muscles

Contents Viscera of neck

• Thyroid gland

• Superior laryngeal nerve • Recurrent laryngeal nerve • Trachea

• Esophagus Carotid Triangle Boundaries Sternocleidomastoid Posterior belly of digastric Superior belly of omohyoid Contents

Carotid sheath MNEMONIC

CAROTID SHEATH CONTENTS I See – Internal Carotid Artery 10 – Vagus Nerve

cc – Common Carotid Artery IV – Internal Jugular Vein Fascial Layers

Superficial cervical fascia Thin layer enclosing platysma muscle Cutaneous nerves Superifical veins Superficial lymph nodes Fascial Layers Deep cervical fascia

Supports muscles, vessels, viscera of neck Condenses to form: 1. Investing layer Trapezius Sternocleidomastoid 2. Pretracheal layer Laryngeal cartilages Thyroid Parathyroid Infrahyoid muscles Fascial Layers Deep cervical fascia 3. Prevertebral layer

Over prevertebral muscles, vertebral column Forms Axillary Sheath

4. Carotid Sheath Common carotid artery Internal carotid artery Internal jugular vein Vagus nerve

Retropharyngeal space “Danger space”

Retropharyngeal abscess à airway compression Tracking to thorax and mediastinum

External Carotid Artery Branches: SAL FOP SM Superior thyroid Ascending pharyngeal Lingual Facial Occipital Posterior auricular Superficial temporal Maxillary Thyroid Gland

Isthmus is at level of 2nd 3rd _{4th tracheal ring}

Blood Supply:

Superior thyroid artery Inferior thyroid artery Thyroidea ima Venous drainage

Superior thyroid vein Middle thyroid vein Inferior thyroid vein PARATHYROID GLAND

Four (4) separate glands

Secretes Parathyroid Hormone Blood Supply: • Superior thyroid artery. • Inferior thyroid artery Larynx Cartilages 3 unpaired: Thyroid Cricoid Epiglottis 3 paired: Arytenoid Corniculate Cuneiform

Intrinsic Laryngeal Muscles TENSES – CRICOTHYROID

RELAXES – THYROHYOID (VOCALIS ) ABDUCTOR – POSTERIOR CRICOARYTENOID ADDUCTORS – TRANSVERSE ARYTENOID

OBLIQUE ARYTENOID Lateral cricoarytenoid Pharynx Parts Nasopharynx Oropharynx Laryngopharynx (hypopharynx ) Circular Muscles Superior constrictor Middle constrictor Inferior constrictor Longitudinal muscles Stylopharyngeus Salphingopharyngeus FOREIGN BODY INGESTION PYRIFORM SINUS

most common site for the lodging of ingested sharp foreign bodies ( fishbones )

CERVICAL PLEXUS

Anterior rami C1-C4 spinal nerves Cutaneous Lesser occipital Greater auricular Transverse cutaneous Supraclavicular CERVICAL LYMPHNODES Level 1 Submental/ Submandibular Level 2 Upper jugular

Level 3 Mid jugular Level 4 Lower jugular Level 5 Suboccipital Level 6 Central THE END

Back and Spine Loubomir E. Antonio, MD Vertebral Column Central pillar of the body Protects the spinal cord

Supports weight of the head and trunk Transmits to hip bones and lower limbs Flexible, Segmented

• Vertebrae • Intervertebral discs Vertebral Column

Cervical: Posterior concavity (Lordosis) Thoracic: Posterior convexity (Kyphosis) Lumbar: Posterior concavity (Lordosis) Sacral: Posterior convexity (Kyphosis) Vertebral Column Parts Body Vertebral arch Pedicles Laminae 7 processes Spinous (1) Transverse (2) Articular (4) Vertebral Column • Spinous process – Directed posteriorly

• Junction of two laminae • Transverse process

– Directed laterally

• Junction of laminae and pedicles Function

– levers

– attachment for muscles, ligaments Vertebral Column

 Articular Process

 Vertically arranged ▪ Two superior ▪ Two inferior

 Pedicles are notched on upper and lower borders ▪ Superior vertebral notch

▪ Inferior vertebral notch Forming Intervertebral foramen

▪ Transmit spinal nerves ▪ And blood vessels Cervical Vertebra

 Characteristics

 Vertebral foramen ▪ Large ▪ Triangular  Superior articular processes

▪ Small ▪ Flat

▪ Face backward, & upward  Inferior articular processes

▪ Face downward & forward Cervical Vertebra

 Characteristics

 Foramen transversarium ▪ Transverse process

▪ Passage of the vertebral artery and veins

 Spines ▪ Small ▪ Bifid Atypical Cervical Vertebrae First cervical vertebra (Atlas) No body, No spinous process Anterior arch

Posterior arch

Lateral mass (each side) Articular surfaces

Upper aspect (Occipital condyles of skull) Lower aspect (Axis)

Atypical Cervical Vertebrae Second cervical vertebra (Axis) Odontoid process

peg-like

Projects upward from superior surface of body Represents body of atlas that has fused with the axis Atypical Cervical Vertebra

Seventh cervical vertebra Longest spinous process NOT bifid

Large transverse process Small foramen transversarium DOES NOT transmit vertebral artery Cervical Vertebral Fracture

Jefferson’s fracture – disruption of the ring of atlas w/ displacement

of lateral masses

Hangman’s fracture – fracture of the odontoid and pedicles of axis Thoracic Vertebra

Characteristics Body

Medium sized, heart-shaped Vertebral Foramen

Small, circular Spines

Long, inclined downward  Characteristics

 Costal facets

▪ Present on sides, and on transverse process

▪ T11, T12 ~ no facets on transverse process

 Superior articular process

▪ Facets face backward, laterally  Inferior articular process

▪ Facets face forward, medially Lumbar Vertebrae

• Characteristics – Body

• Massive, kidney shaped – Pedicles • Strong – Laminae • Thick – Vertebral foramina • Triangular – Transverse processes • Long, slender Lumbar Vertebrae  Characteristics  Spinous processes

▪ Short, flat, quadrangular, project backward

 Superior articular processes ▪ Facets face medially  Inferior articular processes

▪ Factes face laterally No rib facets, no foramina in the transverse processes Sacral Vertebrae

Sacrum

Five rudimentary vertebrae fused together Single wedge shaped bone

Sacral Vertebrae Characteristics Sacral promontory

Anterior upper margin of 1st _{sacral vertebrae} Bulges forward into pelvic cavity

Important obstetric landmark Sacral Vertebrae

Characteristics Sacral canal

Formed from sacral foramina Contains:

Part of cauda equina

Meninges (up to lower border S2) Lower sacral nerve roots Coccygeal nerve roots Filum terminale Sacral Vertebrae Characteristics Sacral Hiatus

Failure of the 5th _{and sometimes 4}th _{sacral vertebra to meet in the} midline

Anterior & Posterior sacral foramina

Passage of anterior and posterior rami of the upper four spinal nerves Sacral Vertebrae

Articulations Upper border (base) 5th _{lumbar vertebrae} Narrow inferior end Coccyx

Laterally Two hip bones Sacroiliac joints Coccygeal Vertebrae Coccyx

Four (4) fused together* Single

Small Triangular

* first coccygeal vertebra commonly not fused with 2nd Atlanto-occipital Joints

between Occipital condyles Lateral masses of the atlas Ligaments

 Anterior Atlanto-occipital membrane  Posterior Atlanto-occipital membrane Movements ( YES Joint )

 Flexion  Extension  Lateral flexion NO rotation Atlantoaxial Joints between

Odontoid process and anterior arch of atlas (1) Lateral masses of bones (2)

Movement ( No Joint )

 Rotation if atlas w/ head on axis Ligaments

Apical – from dens to anterior margin foramen magnum

Alar – lateral to apical ligament

Cruciate – dens to atlas and foramen magnum Membrana tectoria – upward extension of posterior

longitudinal ligament Joints Between Two Vertebral Bodies

Covered by thin plate of hyaline cartilage Intervertebral disc of fibrocartilage in between Ligaments

Anterior longitudinal ligaments Posterior longitudinal ligaments

Continuous bands down the anterior and posterior surface of the vertebral column

from the skull to the sacrum Intervertebral Discs Characteristics

1/4th _{of length of vertebral column}

Thicker in cervical and lumbar regions Annulus fibrosus forms periphery of the disc Fibrocartilage

Collagen fibers arranged in alternating concentric layers Intervertebral Discs

 Characteristics

 Nucleus pulposus forms central part of disc ▪ Ovoid mass of gelatinous material ▪ Normally under pressure ▪ With advancing age,

▪ decrease in water content ▪ Replaced by fibrocartilage  No discs

▪ between first two cervical vertebrae ▪ In sacrum

▪ In coccyx Intervertebral Discs

 Herniation of the nucleus pulposus  Frequently occurs in the

▪ Lower lumbar region (Most common)

 Due to sudden increase in compression load on vertebral column

 Rupture of annulus fibrosus

 Nucleus pulposus herniates posteriorly into vertebral canal

 Compression of spinal nerve roots, spinal nerve, or spinal cord

Joints Between Two Vertebral Arches Synovial joints

 Between adjacent superior and inferior articular processes

Ligaments

 Supraspinous ligament

▪ Connect adjacent spines  Interspinous ligament

▪ Connect adjacent spines  Ligamentum flavum

▪ Connect adjacent laminae Ligamentum Nuchae

▪ Cervical region

▪ Thickening of supraspinous and infraspinous ligaments

Movements of Vertebral Column

 Type and range in regions depend on  Thickness of intervertebral discs

 Shape and direction of the articular processes Cervical region: most movable

Muscles of the Back Groupings

Superficial

Connected with shoulder girdle Intermediate

Involved with movements of the thoracic cage Deep or Postvertebral

Vertebral column Postvertebral Muscles Classification

Superficially running muscles Erector spinae Iliocostalis Longissimus Spinalis Postvertebral Muscles Classification

Intermediate oblique running muscles Transversospinalis Semispinalis Rotatores Multifidus Postvertebral Muscles Classification Deepest Muscles Interspinales Intertransversari Postvertebral Muscles

Muscles of longest length lie superficially

 From sacrum to rib angles, transverse processes, upper vertebral spines

Intermediate length run obliquely

 From transverse processes to the spines Shortest and deepest muscles

 From spines and transverse processes of adjacent vertebrae

Muscular Triangles Auscultatory triangle

Site on back where breath sounds most easily hear via stethoscope Boundaries

Latissimus dorsi Trapezius

Medial border of Scapula Rhomboid major (floor) Muscular Triangles Lumbar Triangle

Boundaries Latissiumus dorsi

Posterior border of the external oblique Iliac crest

Spinal Cord Cylindrical in shape

From Medulla Oblongata (of brain) Begins superiorly at

Foramen magnum End inferiorly at

Lower border 1st _{lumbar vertebrae (Adults)} Occupies upper 2/3rds of the vertebral canal Spinal Cord

Surrounded by three (3) meninges Dura mater Arachnoid mater Pia mater Additonal protection by Cerebrospinal fluid Subarachnoid space Spinal Cord • Enlargements – Cervical

• Origin of brachial plexus – Lumbar

• Origin of lumbar plexus • Lower end

– Conus medularis – Filum terminale

• pia mater prolongation

• From conus medullaris to back of coccyx Spinal Cord

Fissures

Anterior median fissure

Midline on the anterior surface of the cord Posterior median fissure

Midline on the posterior surface of the cord Spinal Cord  Roots (31 pairs)  Anterior ▪ Motor  Posterior ▪ Sensory

▪ w/ posterior root ganglion  Roots in regions

 Upper cervical region

▪ Short, run almost horizontally  Lumbar, Sacral below level of termination of cord

▪ Vertical leash of nerves around filum terminale

▪ Cauda equina Spinal Cord

Roots

Pass though intervertebral foramina

Unite to form spinal nerves which divides into Anterior ramus (large)

Posterior ramus (smaller)

Both contain motor and sensory fibers Blood Supply of Spinal Cord Arteries

Posterior spinal arteries

Arise directly or indirectly from the vertebral arteries Supply posterior 1/3rd _{of spinal cord}

Blood Supply of Spinal Cord Arteries

Anterior spinal arteries Arise from vertebral arteries Unite to form a single artery Supply anterior 2/3rds _{of spinal cord} Posterior spinal arteries

Arise directly or indirectly from the vertebral arteries Supply posterior 1/3rd _{of spinal cord}

Radicular arteries

Branches of regional arteries

Reinforce anterior and posterior spinal arteries

Veins

Drain into internal vertebral venous plexus Meninges of Spinal Cord

 Dura Mater

 External membrane,  Dense fibrous tissue

 Encloses spinal cord and cauda equina  Above, continuous with dura covering brain  Below, dura ends on filum terminale

▪ at level of lower border of the 2nd

sacral vertebra

 Gives sheaths to all spinal nerve roots Meninges of the Spinal Cord

Arachnoid Mater

Delicate, impermeable membrane Lies within the dura, outside the pia

Separated from pia mater by subarachnoid space (filled with cerebrospinal fluid)

Meninges of the Spinal Cord  Arachnoid Mater

 Above, continuous with arachnoid covering the brain

 Below, end on the filum terminale

▪ At the level of lower border of the 2nd

sacral vertebra

 Continues along spinal nerve roots forming small lateral extensions of subsrachnoid space Meninges of the Spinal Cord

 Pia Mater

 Vascular membrane  Closely covers spinal cord

 Thickened on either side between nerve roots (ligamentum denticulatum)

 Extends along each nerve root as far as the spinal nerve

 Inferiorly prolonged off the lower end of the spinal cord as the filum terminale

Lumbar puncture (Spinal Tap)

Patient on the side with vertebral column well flexed Above or Below 4th _{lumbar spine}

Lies within imaginary line between highest points on iliac crests Lumbar puncture

(Spinal Tap)

 Needle passes through the following structures to subarachnoid space  Skin  Fascia  Supraspinous ligament  Interspinous ligament  Ligamentum flavum

 Fatty tissue (internal vertebral venous plexus)  Dura mater

 Arachnoid mater THE END

Thorax

Loubomir E. Antonio,M.D. Bones of the Thoracic Wall Sternum

Manubrium Body of the Sternum Xiphoid Process Ribs Typical Rib Atypical Rib Cervical Rib Costal Cartilages BONE MARROW BIOPSY STERNUM

Site of red hematopoiesis throughout life STERNAL ANGLE OF LOUIS

Articulation of manubrium with the body Landmark

2nd _{costal cartilage}

Intervertebral disc between 4th _{and 5}th _{thoracic vertebrae}

Junction of Ascending aorta and aortic arch

Junction of aortic arch and descending thoracic aorta Bifurcation of the trachea

Junction of the superior mediastinum and inferior mediastinum Ribs

12 pairs

Attached posteriorly to thoracic vertebrae (3) categories

True ribs ( ribs 1 to 7 ) False ribs ( ribs 8 to 10 ) Floating ribs ( ribs 11 and 12 ) TYPICAL RIBS – ribs 3 to 9 ATYPICAL RIBS – ribs 1,2,10,11,12 PARTS OF A TYPICAL RIB Head – attached to vertebral body Neck

Tubercle – attached to transverse process Shaft

Angle Cervical rib Congenital variation 0.5% of people

From transverse process of 7th _{cervical vertebra}

Thoracic outlet syndrome

Pressure on the lower trunk of the brachial plexus or subclavian artery RIB FRACTURES

Ribs 5 to 10

Most commonly fractured ribs Severe localized pain

- most important symptom Flail Chest

- section of chest wall disconnected to the thoracic wall - paradoxic breathing

- underlyinf lung contusion Muscles of the Thoracic Wall Diaphragm

Intercostal Muscles External Intercostal Fibers ~ downward, forward Internal Intercostal

Fibers ~ downward, backward Innermost Intercostal

Fibers ~ transverse, incomplete layer Levatores costarum (12) Serratus posterior Superior Inferior Diaphragm Origin Xiphoid process, lower 6 costal cartilages

1-3 lumbar vertebrae by crura and medial and lateral arcuate ligaments

Insertion Central tendon Embryonic Origin

MNEMONIC: Several Parts Build Diaphragm Septum transversum Pleuriperitoneal fold Body wall Dorsal mesentery Diaphragmatic Hernias Congenital

Incomplete fusion of the septum transversum, pleuroperitoneal fold, and dorsal mesentery from the body wall

3 sites

1. at the back, usually left – Bochdalek’s hernia 2. in front – Morgagni’s hernia

3. thru esophageal hiatus Acquired

- weakness in the musculature 1. Sliding

2. Para esophageal

Diaphragm Action

MOST IMPORTANT muscle of INSPIRATION

Increases vertical diameter of the thorax by pulling down central tendon

Assists in raising the lower ribs Innervation

Phrenic nerve (C3-C5) Needle Thoracentesis

Lifesaving for tension pneumothorax Drain fluid, blood or pus

May be done ANTERIOR and LATERAL at 2nd _{ICS, ABOVE the 3}rd _rib

Tube Thoracostomy 4th _{or 5}th _ICS

preferred site at anterior axillary line

May be done at a lower ICS but NOT LOWER than 5th _{rib on either}

side ( dome of diaphragm ) Intercostal Spaces Spaces between ribs contain External intercostal Internal intercostal Intercostal vein Intercostal artery Intercostal nerve “VAN” à downward Innermost intercostal

Lined internally by endothoracic fascia, & parietal pleura

Diaphragm Actions

Weight lifting muscle Abdominal straining Inspiration

Thoraco-abdominal pump REMEMBER!

“I ate (8), ten (10) EGGs AAT twelve (12)” IVC , right phrenic(T8)

Esophagus, vaGus nerves (T10) Aorta, Azygous vein, Thoracic duct (T12) C 8

E 10 A 12

Paralysis of the Diaphragm

Traumatic/Thrapeutic sectioning of the phrenic nerve

May have to include the accessory phrenic nerve from C5 ( nerve to subclavius )

SNIFF TEST

Penetrating Injuries to the Diaphragm

Any penetrating injury BELOW the NIPPLE anteriorly and the Inferior angle of the SCAPULA

Associated intra abdominal injuries Intercostal Vessels

Each intercostal space

(1) large Posterior intercostal artery (2) small Anterior intercostal arteries Posterior intercostal vein

Drain azygous or hemiazygous veins Anterior intercostal veins

Drain into the internal thoracic and musculophrenic veins Posterior Intercostal Arteries

First 2

- branches of superior intercostal artery, branch of costocervical trunk of subclavian artery Last 9

- branches of the thoracic aorta Anterior Intercostal Arteries

First 6

- branches of the internal thoracic artery Last 5

- branches are from the musculophrnic artery, a terminal branch of internal thoracic artery Internal Thoracic Artery

From first part of subclavian artery

Descends directly behind the first six costal cartilages In front of the parietal pleura

Lies a finger breath lateral to sternum Terminates in 6th _{intercostal space, dividing to}

Superior espigastric artery Musculophrenic arteries Lymphatic Drainage of the thorax Nerves of Thoracic wall Intercostal nerves

Anterior rami of first eleven (11) thoracic spinal nerves Enters intercostal space

Runs inferiorly to intercostal vessels (VAN) In intercostal groove

Between innermost and internal intercostal muscles Intercostal nerves

First six (6) nerves

distributed within their intercostal spaces 7th_{, 8}th_{, 9}th _{intercostal nerves}

Leave anterior ends of the intercostal spaces Passing deep to costal cartilages

Enter abdominal wall 10th_{, 11}th _{intercostal nerves}

Pass forward directly into abdominal wall Intercostal nerves

First intercostal nerve Large branch

Joins anterior ramus of the 8th _{cervical nerve} Forms lower trunk of brachial plexus Remainder is small

Intercostal nerves Second intercostal nerve

Joined by medial cutaneous nerve of the arm by intercostobrachial nerve

Supplies skin of armpit, and upper medial side of arm *area of pain referred to by coronary arterial disease REFERRED PAIN

Pneumonia/Pulmonary thromboembolism

- abdominal pain, tenderness and rigidity Thoracic cavity

Divided into mediastinum medially, and pleurae and lungs laterally Above ~ Thoracic outlet

Anteriorly: superior border of the manubrium sterni Posteriorly: first thoracic vertebra

Laterally: medial borders of the first ribs and costal cartilages Allows passage:

Esophagus Trachea

Many vessels, nerves

Widening of the Mediatinum > 50% or > 8cms

Normally LESS THAN 50% of the transverse diameter of the chest Seen in cardiomegaly, pericardial effusion, pericardial tamponade Shifting of the Mediastinum

IPSILATERAL - side of atelectasis CONTRALATERAL

- Side of tension pneumothorax Mediastinal Infections From a deep infection in the neck From an esophageal perforation Mediastinits

Mediastinoscopy Chamberlain procedure

- obtain samples of tracheobronchial lympnodes through the substernal space

Trachea

Mobile, cartilaginous membranous, fibroelastic tube U-shaped rings

Approx 5in. (13cm) in length, 1in (2.5cm) in diameter Continuation of larynx at lower border of cricoid cartilage (6th

cervical vertebra) Descends in midline of neck

Ends in thorax level of sternal angle (between T4-T5) dividing into Right principal (main) bronchi

Left principal (main) bronchi Compression of the Trachea Enlarged thyroid

Aortic arch aneurysm Bronchi

Right principal (main) bronchus Wider, shorter, more vertical Before entering hilum, gives off Superior lobar bronchus On entering the hilum, divides to Middle lobar bronchus

Inferior lobar bronchus Bronchi

Left principal (main) bronchus Narrower, longer, more horizontal Passes below arch of the aorta In front of esophagus

On entering hilum, divides to Superior lobar bronchus Inferior lobar bronchus Inhaled Foreign Body Common on children

Pins, screws, nuts, bolts, peanuts, chicken bones, toys, tooth Usually enters the RIGHT primary bronchus

Pleurae

Two serous sacs surrounding and covering the lungs Parts

Parietal pleura Lines thoracic wall

Thoracic surface of diaphragm Lateral surface of mediastinum

Sensitive to pain, temperature, touch, pressure Visceral pleura

Outer surfaces of lungs Interlobar fissures Sensitive to stretch Pleurae

Pleural cavity (pleural space)

Slitlike space that separates parietal and visceral pleurae Contains small amount of pleural fluid

Lubricates apposing pleural surfaces Costodiaphragmatic recess

Lowest area of pleural cavity into which the lungs expand during deep

inspiration LUNG HILUM Right

most superior structure Primary bronchus “eparterial” Left

most superior structure Pulmonary artery primary bronchus below the artery hence; “hyparterial” Cervical Dome of the Pleura and Apex of Lungs Vulnerable to stab wounds at the root of the neck

Damage by anesthetist needle in brachial plexus nerve block Lung and Pleural Reflections

Lungs Pleura Midclavicular rib 6 8 Midaxillary 8 10 Paravertebral 10 12 Lungs, lobes and fissures

Right lung Slightly larger Oblique fissure Horizontal fissure Divides right lung into Upper lobe

Middle lobe Lower lobe

Lungs, lobes and fissures Left lung

Only one fissure (oblique fissure) Two lobes

Upper lobe Lower lobe

Bronchopulmonary segments Characteristics

Subdivision of a lung lobe

Pyramidal in shape, apex toward lung root Surrounded by connective tissue

Has own

segmental bronchus, segmental artery, lymph vessels, autonomic nerves

Segmental vein NOT included

in connective tissue between adjacent segments Diseased segment can be removed surgically Blood Supply of the Lungs

Pulmonary arteries

Deoxygenated blood to alveoli Bronchial arteries

- oxygenated blood Pericardium

Middle mediastinum Fibroserous sac enclosing Heart

Roots of great vessels Parts Fibrous pericardium Serous pericardium Pericardial sinuses Nerve supply Phrenic nerves Pericardial Lesions Pericarditis

inflammation of the serous pericardium Hamman’s sign ( pericardial friction rub ) Pericardial tamponade

accumulation of fluid or blood in the pericardial space Beck’s triad ( hypotension, neck vein distention, distant heart sounds )

Pericardiocentesis

Needle is introduced to the left of the xiphoid process in an upward and backward direction in an angle 45 degrees to the skin Prevents damage to the pleura and lungs due to the presence of cardiac notch

Heart

• Hollow muscular organ • Middle mediastinum • Pyramidal • Three (3) surfaces – Sternocostal (anterior) – Diaphragmatic (inferior) – Base (posterior) • Apex

– Directed downward, forward, to the left – 5th _{left intercostal space}

– Approx 3.5in (9cm) from midline Heart

Structure

Divided by vertical septa into four (4) chambers Right atria (anterior)

Left atria (posterior) Right ventricle (anterior) Left ventricle (posterior) Walls w/ three (3) layers

Epicardium: outer visceral layer of serous pericardium Myocardium: thick layer of cardiac muscle

Endocardium: thin inner layer Right Atrium

Consists of Cavity and Auricle

Junction is external vertical groove (sulcus terminalis), which On the inside forms a ridge (crista terminalis)

junction between sinus venosus and right atrium proper Part posterior to ridge ~ smooth walled

Interior of auricle ~ roughened by bundles of muscle fibers (musculi pectinati)

Right atrium Openings

Superior vena cava

Upper part of the right atrium Valveless

Inferior vena cava Larger

Lower part of right atrium Rudimentary valve Coronary sinus

Between inferior vena cava and atrioventricular orifice Rudimentary valve

Right atrioventricular orifice Anterior to inferior vena cava Tricuspid valve

Right atrium Fetal remnants Fossa ovalis Shallow depression

Site of foramen ovale (fetus) Annulus ovalis

Upper margin of fossa ovalis

lie on atrial septum, separating right from left atrium Right ventricle, papillary muscles

• Trabeculae carneae – Papillary muscles

• Attached by bases to ventricular wall • Apex to fibrous cords (chordae

tendineae) to cusps of tricuspid valve – Moderate band

• Large ridge attached to – Septal wall – Atrioventricular wall • Conveys part of right bundle branch

of conducting system – Simple prominent projections Left atrium

Main cavity and Auricle

Interior contains muscular ridges (similar to right) Openings

Pulmonary veins (4) 2 from each lung Posterior wall Valveless

Atrioventricular orifice Mitral valve Left ventricle

Largely behind right ventricle, w/ small portion projecting on the left forms left heart margin and apex

Openings

Atrioventricular orifice Aortic Orifice

Aortic vestible, below Walls

3x thicker than right ventricle Trabecular carneae 2 papillary muscles NO moderator band Heart sounds • First sound – Contraction of ventricles

– Closure of tricuspid and mitral valves • Second sound

– Sharp closure of aortic and pulmonary valves • Best heard

– Tricuspid valve ~ right half of lower end of body of sternum

– Mitral valve ~ apex beat

– Pulmonary valve ~ medial end of 2nd _left intercostal space

– Aortic valve ~ medial end of 2nd _{right intercostal} space

Conducting system

Modified Cardiac Muscle Blood Supply Sinoatrial node (pacemaker) both Atrioventricular node RCA Atrioventricular bundle RCA

Right branch LCA Left branch both

Blood supply of the heart Arterial supply

Right coronary artery Left coronary artery

Venous drainage Coronary sinus

Great cardiac vein Small cardiac vein Middle cardiac vein Anterior cardiac vein

Venae cordae minimae Right vs Left Dominance “Right dominance”

Posterior interventricular artery Large branch of right coronary artery “Left dominance”

Posterior interventricular artery Branch of left coronary artery Coronary Artery Disease Functional end arteries

Acute thrombosis on top of chronic atherosclerosis STEMI vs NSTEMI

Venous drainage Right Atrium

Main venous drainage: CORONARY SINUS ONLY 2 drains directly to right atrium anterior cardiac vein

venae cordis minimae “Thebesian veins” Nerve supply of the heart

Autonomic nervous system via cardiac plexuses Sympathetic fibers

Sinoatrial node, atrioventricular node, cardiac muscles, coronary arteries

Cardiac acceleration Increase force of contraction Dilation of coronary arteries Nerve supply of the heart

Autonomic nervous system via cardiac plexuses Parasympathetic fibers

Vagus nerves

Sinoatrial node, atrioventricular node, coronary arteries Reduced rate

Reduced force of contraction Constriction of coronary vessels

Gross anatomic changes in fetal circulation at birth Closure of foramen ovale due to

decreased pressure in inferior vena cava Increased pulmonary blood flow

Constriction of ductus arteriosus à ligamentum arteriosus Dimished pulmonary vascular resistance

Shift flow across from right to left (fetus) to left to right (neonate) Constriction of ductus venosus à ligamentum venosum Large veins of the thorax

Barchiocephalic veins Superior vena cava Azygous vein

Inferior hemiazygous vein Superior hemiazygous vein Inferior vena cava Pulmonary veins Azygous vein Has variable origin

Commonly formed by union of right ascending lumbar vein and right subcostal vein

Ascends through

aortic opening in the diaphragm at the level of the 5th _{thoracic vertebra}

Arches forward to join superior vena cava Inferior hemiazygous vein

Formed by union of Left ascending lumbar vein Left subcostal vein

Ascends through left crus of the diaphragm to join the azygous vein Superior hemiazygous vein

Formed by union of Fourth intercostal vein Eighth intercostal vein Joins azygous vein

Large arteries of the thorax Aorta

Ascending aorta Arch of the aorta Descending aorta Pulmonary trunk Aorta

• Divided into four parts 1. Ascending aorta 2. Arch of ascending aorta 3. Descending aorta 4. Abdominal aorta First 3 parts, are in the thorax Ascending aorta

Arises from left ventricle

Ascends behind sternum to level of sternal angle Continuous with the arch of the aorta

Three (3) bulges behind each aortic cusp sinuses of the aorta “sinuses of Valsalva”

Branches

Right coronary artery (anterior aortic sinus) Left coronary artery

(posterior aortic sinus) Arch of the Aorta

Continuation of ascending aorta

Arches upward, backward, and to the left Behind the manubrium sterni and In front of the trachea

Level of the sternal angle Continous with descending aorta Related inferiorly to

root of the left lung Ligamentum arteriosum Left recurrent laryngeal nerve Bifurcation of the pulmonary trunk Arch of the Aorta

Three (3) Branches from convex surface Brachiocephalic artery

Left common carotid artery Left subclavian artery Descending Aorta

Continuation of the arch of the aorta

Left side of lower border of the body of the 4th _{thoracic vertebra}

(sternal angle)

Descends through posterior mediastinum until anterior surface of 12th _{thoracic vertebra}

Enters the abdomen behind the diaphragm Becomes continous with abdominal aorta Descending aorta

Branches

Posterior intercostal arteries

Pass to the lower nine intercostal spaces Subcostal arteries

Along lower border of 12th _{rub to enter abdominal wall} Pericardial arteries

Esophageal arteries Bronchial arteries Lymph vessels Thoracic duct

Root of the left side of neck Lymph from

Lower limbs Pelvic cavity Abdominal cavity Left side of thorax Left side of head, neck Left upper limb At termination, receives

left jugular, subclavian, mediastinal lymph trunks

But these vessels may drain independently into neighboring great veins

Lymph vessels Thoracic duct Begins in abdomen as Cisterna chyli (a dilated sac)

Ascends through aortic opening in diaphragm right side of the descending aorta Reaches left border of esophagus Follows esophagus to root of neck

Turns laterally behind carotid sheath

Enters beginning of left brachiocephalic vein Lymph vessels

Right lymphatic duct Root of right side of neck,

beginning of right brachiocephalic vein Drains lymph from

Right side head, neck Right upper limb Right side of thorax Sometimes absent

Large nerves of the thorax Vagus nerve

Phrenic nerve

Thoracic part of sympathetic trunk Vagus nerves

Right vagus nerve

Crosses anterior to subclavian artery Descends laterally to the trachea Medial to azygous vein

Runs behind root of right lung Contributes to the pulmonary plexus Posterior to esophagus

Contributes to esophageal plexus

Leaves thorax and enters abdomen through esophageal opening Vagus nerves

Left vagus nerve

Descends into thorax between Left common carotid Left subclavian arteries Descends behind root of left lung Contributes to pulmonary plexus Anterior to esophagus

Contributes to esophageal plexus Enters abdomen through esophageal opening Phrenic nerves

From anterior rami of 3rd_{, 4}th_{, 5}th _{cervical nerves} Right phrenic nerve

Descends in thorax along right side of vena cava In front of root of right lung

Passes over pericardium into the diaphragm Phrenic nerves

Left phrenic nerve

descends along left side of left subclavian artery Crosses left side of the aortic arch and left vagus nerve Passes in front of root of left lung

Descends on pericardium into diaphragm Phrenic nerves

The ONLY motor supply to the diaphragm Sensory branches to

Pericardium

Mediastinal parietal pleura

Pleura covering upper and lower surfaces of diaphragm Thoracic part of sympathetic trunk

Most lateral structure in the mediastinum 11-12 segmentally arranged ganglia stellate ganglion

First ganglion often fused with inferior cervical ganglion Downward on heads of the ribs

Leaves thorax passing behind medial arcuate ligament Continuous with lumbar part of sympathetic trunk Thoracic part of sympathetic trunk

Branches

Cardiac, Aortic,Pulmonary, Esophageal branches From first five ganglia

Splanchnic nerves Supply abdominal viscera Greater splanchnic Ganglia 5-9 Lesser splanchnic Ganglia 10-11 Lowest splanchnic Last thoracic ganglion Esophagus Muscular tube Approx 10in (25cm) Continuous w/ pharnyx

Opposite 6th _{cervical vertebrae} Passes through diaphragm Level of 10th _{thoracic vertebra} Three (3) constrictions Beginning

Crossing of left bronchus Piercing the diaphragm Esophagus

Blood supply Upper 3rd_:

inferior thyroid artery Inferior thyroid vein Middle 3rd_:

branches from descending thoracic aorta Azygous vein

Lower 3rd_: Left gastric artery Left gastric vein

à tributary to portal vein à portosystemic anastomosis Thymus

Flattened Bilobed structure

Between sternum and pericardium Continues to grow until puberty Imporant source of T-lymphocytes The End Abdomen Loubomir E. Antonio, M.D. Surface Markings 2 Vertical lines

- mid point of ASIS and symphysis pubis 2 Horizontal lines Subcostal plane: L3 Intertubercular plane: L5 9 Regions Epigastrium R and L Hypochondriac Umbilical R and L Lumbar Hypogastric R and L Iliac Transpyloris Plane - Addison’s plane

- Level of L1 ( 9th _{costal cartilage )}

Structures

fundus of GB

termination of adult spinal cord pylorus of stomach

neck of pancreas hilum of kidney ANTERIOR ABDOMINAL WALL Skin

Superficial fascia

superficial fatty “Camper’s fascia” deep membranous “Scarpa’s fascia”

- fades laterally and above

- inferiorly fuses with deep fascia of the thigh - forms a tubular sheath for the penis/clitoris - attached to the sides of pubic arch ( Colle’s fascia )

- fuses with perineal body and perineal membrane Deep fascia Muscles Nerves Skin Nerve Supply From Anterior Rami of

• lower six (6) thoracic

– Lower 5 intercostal nerves – Subcostal nerves

• First lumbar nerves – Iliohypogastirc – Ilioinguinal nerves Skin Blood Supply Arteries • Midline

– Superior epigastric artery – Inferior epigastric artery • Flanks

– Intercostal – Lumbar

– Deep circumflex iliac arteries Skin

Blood Supply Veins

• Above

– Axillary vein

– via Lateral thoracic vein

• Below

– Femoral vein Via

– Superficial epigastric vein – Great saphenous veins Skin

Blood Supply Veins

Connection between superior and inferior vena cavae Small paraumbilical veins

Along ligamentus teres to portal vein “Caput Medusae” Skin Lymph Drainage Superficial/ Cutaneous Above umbilicus

Anterior axillary lymph nodes Below umbilicus

Superificial inguinal lymph nodes Rectus Sheath

Long fibrous sheath aponeuroses Contents:

Rectus abdominis

Anterior rami of lower 6 thoracic nerves Lymph vessels

Superior and inferior epigastric vessels Pyramidalis

Rectus Sheath

Between Costal margin and ASIS

Internal oblique splits to cover rectus abdominis Below ASIS and Above pubis

All aponeuroses pass anteriorly Deficient posteriorly

Arcuate line of Douglas

- lower crescent shaped edge of the posterior wall Rectus Sheath

Linea alba Fibrous band

Fusion of aponeurosis at midline

from xiphoid process to pubic symphysis Transverse Tendinous intersections (1) Level of xiphoid

(1) in between (1) Level of umbilius Linea Semilunaris “Spiegelian Line”

Lateral edge of the rectus abdominis

Crosses margin of tip of the ninth costal cartilage Conjoint Tendon

Internal oblique Lower free border Lowest tendinous fibers

joined by transversus abdominis

Strengthens medial half of posterior wall of inguinal canal Inguinal Ligament

Poupart’s ligament

Lower border of External oblique aponeurosis

Connects Anterior Superior Iliac Spine (ASIS) to pubic tubercle Medial end: lacunar ligament (Gimbernat’s ligament) Continuous with pectineal ligament (Cooper’s ligament) ~ thickening of periosteum

Lower border, Attached to fascia lata Fascia Transveralis

Thin layer of fascia lining transveralis muscle Continuous with fascia iliaca (of ilacus muscle) Together forms femoral sheath

Femoral sheath = FT + FI Inguinal Canal

Length Approx 1.5in (4cm)

Parallel and above inguinal ligament Deep inguinal ring

Oval opening in Transveralis fascia Above inguinal ligament

Margins attachment for internal spermatic fascia Superficial inguinal ring

Triangular shaped defect on External oblique aponeurosis Above and medial to pubic tubercle

Margins give attachment to external spermatic fascia Inguinal Canal

Walls Anterior

• External oblique aponeurosis • Internal oblique

Posterior

• Conjoint tendon, medially • Fascia transveralis, laterally Superior

• Arching fibers of the internal oblique and transversus Inferior

• Inguinal and lacunar ligaments Inguinal Canal

Function

Allows structures to pass from Testes to Abdomen: Spermatic cord

Uterus to labium majus: Round ligament of uterus Both sexes transmit Ilioinguinal nerve

Hesselbach’s Triangle Medially: Rectus abdominis Inferiorly: Inguinal ligament Laterally:

Inferior epigastric vessels Inguinal Hernia

Site of potential weakness in both sexes Above inguinal ligament

- lateral to inferior epigastric vessels Indirect Inguinal Hernia - medial to inferior epigastric vessels

Direct Inguinal Hernia Below inguinal ligament

Femoral hernia Spermatic Cord Contents

MNEMONIC: Protruding Piles Don’t Contribute To A Good Sex Life Pampiniform plexus

Processus vaginalis remnants Deferens, vas

Cremasteric artery Testicular artery Artery to vas

Genital branch, genitofemoral nerve Sympathetics

Lymphatics Processus vaginalis

Peritoneal diverticulum formed in fetus

Passes through lower part of anterior abdominal wall to form inguinal canal