Anatomy Week 3

Front 1

metacarpo-phalangeal joint

Back 1

aka MCP
--flexion, extension, abduction

Front 2

Interphalangeal joints

Back 2

IP
-flexion and extension
-DIP or PIP

Front 3

Anatomical snuff box

Back 3

Anterior border: tends of abductor pollicis longus and extensor pollicis brevis

posterior border: extensor pollicis longus

--radial artery lies on teh floor; scaphoid and trapezium can be palpated here

Front 4

Extensor expansion

Back 4

aponeurois formed by extesnor tendons as they reach the phalanges

-once central and two lateral bands are the common insertion for the extensors, interossei, and lumbrical muscles

Front 5

Atrophy of intrinsic hand muscles

Back 5

due to damage to the ulnar nerve

determine by examining the dorsal interossei

Front 6

Radial nerve in the hand

Back 6

divides into superficial nad deep branches after it enters the forearm; once out of the supinator, the deep branch becomes the posterior interosseous

supplies dorsum of hand not supplied by ulnar nerve

Front 7

ulnar nerve in the hand

Back 7

supplies medial third of the dorsum of the hand and the skin of the small finger/medial half of the ring finger. also supplies nail beds on posterior side of hand, along with the median nerve

Front 8

compartments of the hand

Back 8

medial fibrous septum separates the hypothenar compartment from the midpalmar potential space and the thenar space above it

lateral fibrous septum etends to the 3rd metcarapl, forming the thenar and adductor muscle compartments as well as teh tehnar potential space between them

fascial spaces may become infected

Front 9

palmar aponeurosis

Back 9

lies over the long flexor tendons and other tissues in the center of the palm

Front 10

fibrous digital sheats

Back 10

enclose the flexor tendons and their synovial sheaths

Front 11

Boundaries of the neck

Back 11

superior:superior nuchal line of cranium, mastoid processes, lower margin of mandible
inferior: jugular notch of sternum, clavicle, 1st rib

--neck thought of as the tissue surrounding the seven cervical vertebrae
--its fascial layers important as a barrier to liquid

Front 12

superficial fascia of the neck

Back 12

aka tela subcutanea
--surrounds entire neck
--contains the platysma

Front 13

Deep fascia of the neck

Back 13

--surrounds the muscles and viscera of the neck
--separate the neck into compartments
--superficial, prevertebral, and pretracheal layers

Front 14

superficial layer of deep fascia of the neck

Back 14

aka investing fascia
--surrounds entire neck and encloses trapezius and SCM

Front 15

Prevertebral layer of fascia

Back 15

--second layer of deep fascia of neck
--encloses vertebral column and surrounding muscles (anterior, middle, posterior scalenus muscles, etc.)
--axillary sheath is continuation of prevertebral layer

Front 16

Pretracheal layer of fascia

Back 16

aka visceral layer
--encloses cervical viscera (thyroid, trachea, esophagus) and hyoid muscles
--posterior superior portion of this fascia called the buccopharyngeal fascia. it contacts prevertebral fascia posteriorly

Front 17

Carotid sheath

Back 17

formed by condensation of all deep fascia layers and encloses the common carotid artery, internal jugular vein and the vagus nerve

Front 18

retropharyngeal space

Back 18

--potential space in the neck known as the danger space
--anterior to prevertebral fascia, but posterior to the buccopharyngeal fascia. COntinous with upper and middle mediastinum; infections originating in the oral region can track into peicardium, potentially causing cardiac tamponade

Front 19

suprasternal space

Back 19

--superior to sternum, formed by a spolit in the investing fascia as it attaches to manubrium.

--contains jugular arch

Front 20

pretracheal space

Back 20

--anterior to the thyroid cartilage and trachea, but posterior to pretracheal fascia
--continuous with anterior mediastinum of thorax

Front 21

superficial and lateral muscles of neck

Back 21

platysma, SCM, trapezius

Front 22

SCM

Back 22

--divides each side of neck into anterior and posterior triangles

Front 23

platysma

Back 23

--thicker in men than women
--located in superficial fascia
--facial expression muscles

Front 24

Posterior triangle

Back 24

--formed by trapezius muscle, SCM, and clavicle
--further subdivided by inferior belly of omohyoid muscle
--larger, superior of the triangles is occipital triangle
--inferior triangle is supraclavicular (subclavian tirangle)

Front 25

occipital triangle boundaires

Back 25

--trapezius, SCM, inferior belly of omohyoid muscle
--floor:splenius capitis, leavtor scapulae, scalenes.

Front 26

supraclavicular triangle boundaries

Back 26

--inferior belly of omohyoid, SCM, and clavicle
--floor: anterior scalene

Front 27

Anterior triangle

Back 27

--inferior margin of mandible, SCM, anterior midline
--subdivided into digastic/submandibular triangle, submental triangle, carotid triangle, muscular tirnagle

Front 28

digastric triangle

Back 28

aka submandibular
--anterior belly of digastric muscle, posterior belly of digastric, and inferior margin of mandible
--floor: mylohyoid and hyoglossus

Front 29

submental triangle

Back 29

unpaired area bounded by the anterior bellies of the left and right digastric and the hyoid bone.
Floor: mylohyoid muscles

Front 30

Carotid triangle

Back 30

posterior belly of digastric, SCM, superior belly of omohyoid

Front 31

Muscular triangle

Back 31

: superior belly of omohyoid, SCM, midnline from sternum to hyoid.

floor: infrahyoid muscles

Front 32

Torticollis

Back 32

head is flexed laterally to the affected side and rotated away from the affected side

--caused by persistent contraction or shortening of SCM

--infants: can be due to prenatal development of fibrou tumor or damage to muscle during birth
--adults:neurological

Front 33

Nerves of posterior triangle

Back 33

--Nerve supply is from spinal accessory nerve and branches of the cervical plexus
--CN XI innervates SCM and trapezius; is also important landmark; separates occipital triangle into superior carefree zone and an inferior danger zone filled with arteries and nerves
--sensory nervres from cervical plexus:
-Lesser occipital
-Great auricular
-Transverse cervical
-Supraclavicular

--brachial plexus can be identified between anterior and middle scalenes of the occipital triangle

Front 34

Erb's point

Back 34

aka nerve point of the neck
--sensory cutaneous nerves (lesser occipital, great uaricular, transverse cervical, supraclavicular) emerge together around the middle of the posterior border of the sternocleidomastoid in the posterior triangle

Front 35

Branches of brachial plexus originating in the neck

Back 35

Dorsal scapular nerve C5 (from root) pierces the middle scalene and innervates the rhomboids and levator scapulae

--Long thoracic nerve (C5-7) arises from the roots of brachial plexus and innervates serratus anterior

--nerve to subclavius muscle

--suprascapular nerve is a branch of superior trunk of brachial plexus and innervates supra and infra spinatus muscles

Front 36

suprascapular nerve damage

Back 36

often caused by fracutre of middle third of clavicle

-->weak infra and supra spinatus muscles

Front 37

Cervical rib

Back 37

--enlarged process of C7

--traps neurovascular bundle containing brachial plexus as it passes between the clavicle and 1st rib, resulting in the compression of the brachial plexus

-->chronic compression leads to wasting of muscles in the hand

--hypertrophy of the anterior scalene muscle might also have the same effect

Front 38

cervical plexus block

Back 38

inject anesthesia along posterior border of sternocleidomastoid

Front 39

brachial plexus block

Back 39

--inject anesthesia posterior to the middle of the clavicle

Front 40

Arteries of hte posterior triangle

Back 40

--major arterial supply is from branches of subclavian artery
--thyrocervical trunk gives rise to transverse cervical artery and suprascapular artery
--deep cervical artery, a branch of the costocervical trunk
--occipital artery supplies the superior region of the posterior triangle (it is a branch of external carotid)

Front 41

dorsal scapular artery

Back 41

name of the deep branch of the transverse cervical artery when it does not arise from the thyrocervical trunk but rather from the third divsion of the subclavian artery

Front 42

deep cervical artery

Back 42

supplies splenius capitis and cervicis

--terminal branch of the costocervical trunk (along with the superior intercostal artery)

Front 43

external jugular vein

Back 43

--major named vessel in posterior triangle
-forms behind mandible and descnes on surface of SCM into posterior triangle
--joins subclavian vein at base of triangle
--tributaries may include: posterior auricular vein, retromandiublar vein and its posterior division, transverse cervical vein, suprascapular vein, anterior jugular vein

Front 44

External jugular vein as a surface landmark

Back 44

--usually on visible a short distance above the clavicle
--when venous pressure rises, may be visible along its entire course
--could be indication of heart failure, obstruction fo the superior vena cava, enlarged supraclavicular lymph nodes, or a general increase in intrathoracic pressure

--easily severed; may suck air in due to negative intrathoracic pressure when its lumen is held opn by the superficial layer of deep fascia

Front 45

subclavian vein clinical significance

Back 45

--frequently used to introduce catheters for measurement of cardiac pressure or drug delivery

-insert needle infereior to clavicle and and moved medially along the posterior surface until the wall of hte vessel is penetrated

Front 46

boundaries of hte muscular triangle

Back 46

formed by the superior belly of the omohyoid, teh SCM, and the midline from the sternum to the hyoid bone

Front 47

infrahyoid muscles

Back 47

aka strap muscles

--inferior the hyoid bone and arranged into superficial and deep layers. all of them are named by their attachments (omohyoid, sternohyoid, thyrohyoid, sternothyroid)

Front 48

Thyroid gland

Back 48

--endocrine gland crucial for maintaining homeostasis. left and right lobes attached by isthmus
--pyramidal lob often present, arising on superior margin of isthmus (arises from vestige of thyroglossal duct

--follicular cells secrete thyroxin (stimulates metabolism). parafollicular cells secrete calcitonin

Front 49

parathyroid glands

Back 49

embedded in posterior surface of thyroid gland

--4 overall, 2 on each side

--inferior 2 may be ectopic (in CT outside thyroid gland

--secreted parathyroid hormone

Front 50

Problems with thyroid gland migration

Back 50

--normally originates at base of tongue and descneds anteriorly to hyoid bone and trachea along thyroglossal duct

--might not migrate at all, might leave some tissue in the duct (duct normally degenerates) which is more common. often this tissue connects with the isthmus to form pyramidal lobe.

--use iodine to detect ectopic sources

--sometimes find accessory thyroid glands within thymus or on surface of thyrohyoid

Front 51

Goiter

Back 51

--enlarged thyroid gland, releases excess hormone into blood.

--since thyroid constrained by pretracheal fascia, may result in compression of trachea, esophagus, and recurrent laryngeal nerve

-treated surgically by reudcing size of thyroid gland or medically

Front 52

Thyroid carcinoma

Back 52

--gland enlargement, requires total thyroidectomy. Risk of inadvertently removing parathyroid glands; decline in serum calcium produces convulsive tetany

Front 53

Insertion of a breathing tube

Back 53

thryoid gland makes this risky

-safest place is inferior to cricoid cartilage (to protect laryngeal apparatus) and superior to the thyroid isthmus (to protect thyroid venous drainage or thyroid ima artery)
-->incise trachea at level of upper tracheal rings (tracheostomy)

emergency conditions: cricothryotomy generally employed. incisions through cricothyroid membrane, which is superficial and not highly vascularized. risk of damage to vocal folds

Front 54

carotid sheath

Back 54

--formed by condensation of all three eep fascia layers
--encloses common carotid artery, internal jugular vein, and vagus nerve

Front 55

Cervical plexus

Back 55

--formed by anterior rami of cervical nerves C1-C4
--Muscular branches:
----ansa cervicalis (c1-c3) innervates 3 of the infrahyoid muscles except thyrohyoid
----phrenic nerve (c3-c5) innervates diaphragm
--cutaneous branches: innervate skin of neck
----lesser occipital nerve
----great auricular nerve
---transverse cervical nerve
----supraclavicular nerve

Front 56

Carotid triangle contents

Back 56

carotid sheath
-cervical plexus
--infrahyoid muscles
--external carotid artery and its branches
--carotid sinus and carotid body
--nerves (vagus, spinal accessory, hypoglossal nerve, and branches of superior laryngeal nerve of CN X)

Front 57

ansa cervicalis

Back 57

--superior root from C1 travels with Cranial nerve XII but never joins it
--inferior root from C2/C3 descends along internal jugular vein
--two branches join in a loop within the fascia superficial to carotid sheath
--another nerve from C1 branches distally from CN XII to innervate thyrohyoid and geniohyoid

Front 58

Common carotid artery

Back 58

rises in carotid sheath alongside internal jugular and CN X to superior border of thyroid cartilage
--divids into external and internal (internal doesn't branch any further

Front 59

External carotid

Back 59

--8 branches
--anterior branches: superior thyroid artery, lingual artery, facial artery
--posterior branches: occipital artery, posterior auricular artery
--Medial branch: ascending pharyngeal artery
--terminal branches: superficial temporal artery, maxillary artery

Front 60

Carotid sinus

Back 60

located at bifurcation of common carotid
--dilation of beginning of internal carotid artery
--baroreceptor
--innervated by branches of CN IX and X

Front 61

Carotid body

Back 61

--small tissue mass suspended on the posterior surface of bifurcation
--chemoreceptor for O2/Co2 levels
--innervated by branches of CN IX and X

Front 62

Submandibular triangle contents

Back 62

submandibular gland, submandibular lymph nodes, facial artery and vein, mylohyoid muscle, stylohyoid muscle, hypoglossal and mylhyoid nerves

Front 63

Suprahyoid muscles

Back 63

superior to hyoid bone, include stylohyoid, digastric, mylohyoid and geniohyoid

Front 64

fibrous raphe

Back 64

fusion of tendons of mylohyoids--midline

Front 65

fibrous raphe

Back 65

fusion of tendons of mylohyoids--midline

Front 66

fibrous raphe

Back 66

fusion of tendons of mylohyoids--midline

Front 67

Submandibular gland

Back 67

--secretes saliva into oral cavity
--wraps around posterior free edge of mylohyoid muscle
--superficial and deep lobes divided by mylohyoid
--submandibular duct emerges from deep lobe to open under tongue
--blood supply: branches of lingual and facial arteries; drains through lingual and facial veins
--controlled by CN VII
--parasympathetic innervation

Front 68

Submandibular gland

Back 68

--secretes saliva into oral cavity
--wraps around posterior free edge of mylohyoid muscle
--superficial and deep lobes divided by mylohyoid
--submandibular duct emerges from deep lobe to open under tongue
--blood supply: branches of lingual and facial arteries; drains through lingual and facial veins
--controlled by CN VII
--parasympathetic innervation

Front 69

Submandibular gland

Back 69

--secretes saliva into oral cavity
--wraps around posterior free edge of mylohyoid muscle
--superficial and deep lobes divided by mylohyoid
--submandibular duct emerges from deep lobe to open under tongue
--blood supply: branches of lingual and facial arteries; drains through lingual and facial veins
--controlled by CN VII
--parasympathetic innervation

Front 70

Submental triangle contents

Back 70

--submental lymph nodes

Front 71

Submental triangle contents

Back 71

--submental lymph nodes

Front 72

Submental triangle contents

Back 72

--submental lymph nodes

Front 73

Root of the neck boundaries

Back 73

lateral: 1st ribs and coast cartilages
anterior: manubrium
posterior: body of T1

Front 74

Root of the neck boundaries

Back 74

lateral: 1st ribs and coast cartilages
anterior: manubrium
posterior: body of T1

Front 75

Root of the neck boundaries

Back 75

lateral: 1st ribs and coast cartilages
anterior: manubrium
posterior: body of T1

Front 76

Contents of root of neck

Back 76

--apex of lung and cupola of pleura (aka cervical pleura)
--supraclavicular brachial plexus
--viscera of neck
--infrahyoid muscles

Front 77

Contents of root of neck

Back 77

--apex of lung and cupola of pleura (aka cervical pleura)
--supraclavicular brachial plexus
--viscera of neck
--infrahyoid muscles

Front 78

Contents of root of neck

Back 78

--apex of lung and cupola of pleura (aka cervical pleura)
--supraclavicular brachial plexus
--viscera of neck
--infrahyoid muscles

Front 79

Triangle of the vertebral artery

Back 79

--in root of neck
--bounded by anterior scalene, longus colli, first part of subclavian
--important for relationship to subclavian and vertebral arteries

Front 80

Interscalene tirangle

Back 80

--between anterior and middle scalenes and first rib.
--contains root of brachial plexus and subclavian artery

Front 81

subclavian artery

Back 81

3 parts, divided by anterior scalene muscle
1st part: VIT (vertebral artery, thyrocervical trunk, internal thoracic artery)
2nd part: costocervical trunk
3rd part: may have dorsal scapular

Front 82

Vertebral artery

Back 82

--originates in 1st part of subclavian
--projects superiorly through vertebral triangle and passes deep to anterior scalene to ascend through foramina transversarii

Front 83

thyrocervical trunk

Back 83

--inferior thyroid artery
--transverse cervical artery
--suprascapular artery

Front 84

Internal thoracic artery

Back 84

--1st part of subclavian
--projects inferiorly deep to sternum

Front 85

Costocervical trunk

Back 85

second or third part of subclavian
--gives rise to deep cervical artery and superior intercostal artery
--deep cervical artery may arise on its own in third part of subclav = dorsal scapular

Front 86

subclavian vein

Back 86

anterior to anterior scalene
--continuation of axillary vein
--branches parallel artery branches

Front 87

thoracic duct

Back 87

empties into venous angle between left internal jugular and left subclavian veins

Front 88

recurrent laryngeal branches

Back 88

--branche of vagus nerve
--ascend along sulcus between esophagus and trachea

Front 89

phrenic nerve

Back 89

--descends along surface of anterior scalene before passing deep to first rib

Front 90

sympathetic trunk

Back 90

--surface of longus colli muscle deep to carotid sheath
--three sympathetic ganglia along its length
--superior (C1 and C2 level), middle (C6) and inferior usually merges with 1st thoracic gangiion-->stellate ganglion

Front 91

stellate ganglion

Back 91

aka cervicothoracic ganglion
--fusion of inferior cervical ganglion of sympathetic trunk with 1st thoracic ganglion

Front 92

nerve position with regards to carotid sheat

Back 92

--vagus: within
--ansa cervicalis: anterolateral surface
--cervical plexus/brachial plexus: posterolateral
--sympathetic trunk: posteromedial
--superior and recurrent laryngeal nerves: medial to sheath

Front 93

vascular spasms

Back 93

--can be treated by blocking sympathetic function
--e.g. inject anesthetic around stellate ganglion to relieve spasms in brain and upper limb. if successful, perform surgery

Front 94

Horner's syndrome

Back 94

--risk coming from sympathetic ganglion block or surgical resection
--ipsilateral
--learn more in block 2

Front 95

risks of surgical procedures at root of neck

Back 95

--damage to recurrent layrngeal nerves, resulting in hoarseness due to paralysis of laryngeal muscles, particularly posterior cricoarytenoids

Front 96

3 zones for penetrating injuries of neck

Back 96

Zone I: root of neck inferior to cricoid cartilage
Zone II: superior neck between cricoid cartilage and angle of mandible
Zone III: region superior to angle of bandible

Zone I and III injuries most serious b/c they may affect the airways (more difficult to visualize and repair).

Zone II injuries most common, and quick to treat.