Exam 2 (ALL) - Upper Limb & Thorax
how many types of fibers are there & what are their names?
4 -gen somatic efferent (GSE) -gen somatic afferent (GSA) -gen visceral efferent (GVE) -gen visceral afferent (GVA)
how many muscles are in the deep layer of the anterior forearm?
3 muscles
how many thenar muscles are they and what are they innervated by?
3 thenar muscles work to flex, ABDuct + oppose the thumb - ALL innervated by median nerve
what are the 4 main components of the R atrium?
-(valveless) openings for the SVC, IVC and coronary sinus - ALL of which drain into the R atrium -pectinate muscles = ridges w/in the wall of the atria (Derived from primitive atrium) -crista terminalis - visual delineation btw tissue derived from primitive atrium vs the vessels incorporating themselves into the atrial wall (which = the smooth part) ---therefore crista terminalis surrounds the fossa ovalis -fossa ovalis = oval-shaped depression in the interatrial walls which is a remnant of the foramen ovale - the shunt that pushes blood from R --> L atrium ---if the foramen ovale stays open after birth, it's known as the "patent foramen ovale" (PFO)
what are the 3 branches of the RCA (right coronary artery)?
-1st branch of RCA = sinoatrial (SA) nodal branch which supplies the R atrium + SA node -as the RCA travels thru the coronary sulcus, it gives off the R marginal branch which supplies the R aspect of the heart and travels toward the apex -the RCA finally gives off the PIA/PDA which supply the posterior heart + posterior 1/3 of IVS
asymmetry btw pulm arteries + veins?
-2 pulm arteries (1 for each side) -4 pulm veins (2 for each side - superior + inferior on BOTH sides)
how many layers + what are the layers of the heart wall?
-3 main layers of the heart wall ---epicardium = outermost layer composed of parietal + visceral pericardium ---myocardium = heart muscle (therefore largest layer) ---endocardium = innermost layer that's simple squamous epithelium
how many and what are the spec pathways preganglionic symp fibers can take?
-3 major pathways that symp axons can take to get to various regions of the body: ---preganglionic cell body sends its preganglionic axons to paravertebral ganglion at SAME level, synapses there, and then sends postganglionic fibers to organ ------this = mostly seen w/intercostal nerves ---preganglionic cell body sends its axons to a paravertebral ganglion at a DIFF level and synapses on a postganglionic cell body ------this = to get into cervical/sacral regions ---preganglionic cell body sends its axons thru the paravertebral ganglia W/O synapsing and then it travels to a prevertebral ganglia for synapse and then mostly goes to abd organs ------this = for splanchnic nerves
side branches of posterior cord?
-3 side branches which should theoretically have all 5 brachial plexus levels BUT it seems to be variable btw individuals -collectively, these 3 side branches/nerves = known as "subscapular nerves" ---upper + lower subscapular nerves innervate subscapularis muscle (1 of the 4 rotator cuff muscles) ---lower subscapular ALSO innervates teres major (similar to latissimus dorsi) ---middle subscapular nerve aka thoracodorsal nerve innervates latissimus dorsi
how many muscles are in the superficial layer of the anterior forearm and what do they all share in common?
-4 muscles in the superficial layer of anterior forearm -commonality among all these muscles = that they're all from the medial epicondyle so overuse can ==> golfer's elbow
order of terms in the brachial plexus + their #s?
-5 ventral ramii (roots) together ==> 3 trunks ---C5 & C6 ==> superior trunk; C7 ==> middle trunk; C8 & T1 ==> inferior trunk -3 trunks ==> 6 divisions b/c each trunk ==> 1 anterior + 1 posterior division for a total of 3 anterior + 3 posterior divisions -6 divisions ==> 3 cords ---top 2 anterior divisions ==> lateral cord; last/bottom anterior division ==> medial cord; all 3 posterior divisions ==> posterior cord -3 cords ==> 5 terminal branches, each of which = a nerve (cords also have side branches coming off of them) ---musculocutaneous nerve, median nerve, axillary nerve, radial nerve, ulnar nerve
where do ALL preganglionic parasymp fibers synapse onto?
-ALL preganglionic parasymp fibers synapse onto postganglionic cell bodies w/in the walls of the organs (they may pass thru ganglia)
where is the IMLCC located in the thoracic + upper lumbar spinal cord?
-IMLCC = located in the lateral horn of the thoracic + upper lumbar spinal cord so that's where our preganglionic symp cell bodies = found
fxn of the L side of the heart and what it receives from where?
-L atrium receives newly oxygenated blood from pulm veins & L ventricle pumps blood thru ascending aorta --> entirety of the body (except for the lungs)
what are the 3 branches of the LCA?
-LCA = a very large artery in terms of diameter/lumen BUT it's a very short segment b/c it almost immediately bifurcates into: ---anterior interventricular artery which supplies the anterior aspect of heart + 2/3 of IVS + apex of heart ---circumflex branch which wraps around to the posterior aspect in coronary sulcus --LCA also ==> L marginal artery which supplies the L aspect of heart + L ventricle
what is the mediastinum in general, and its location?
-Mediastinum houses the viscera - organs outside of the lungs w/in the thorax -mediastinum extends from superior thoracic aperture to the inferior thoracic aperture (covered by our diaphragm which attaches to sternum at T9 BUT domes all the way down until T12) ---anterior border = sternum while the posterior border = thoracic vertebral bodies
how many muscles are in the intermediate layer of the anterior forearm?
-ONLY 1 muscle in the intermediate layer of the anterior forearm - this 1 muscle = connected to 4 tendons going to digits 2-5
pulmonary vasculature
-R + L pulm arteries branch from the pulm trunk and then follow the path of the bronchi as they divide into smaller structures to reach the alveolar sacs where gas exchange occurs -pulm veins return oxygenated blood to heart and are intersegmented (btw the tertiary bronchi + pulm arteries)
lung asymmetry
-R lung has 3 lobes (superior, middle, inferior) while L lung only has 2 (superior, inferior) b/c of the heart's position on the L side
which main bronchus = more likely to get obstructed when inhaling something and why?
-R main bronchus = more likely to get obstructed when inhaling something b/c of the angle + size - R main bronchus = more vertical + has a larger diameter (while L main bronchus = more to the side d/t the heart)
fxn of the R side of the heart & what it receives from where?
-R side of heart pumps blood to lungs b/c it receives deoxygenated blood from superior + inferior vena cava (SVC + IVC) & coronary sinus ---spec, the R atrium pumps blood --> R ventricle --> pulm trunk --> lungs
asymmetry w/in the hilum?
-R side: pulm arteries = anterior to main bronchus -L side: pulm arteries = superior to main bronchus
R vagus pathway
-R vagus nerve enters the superior mediastinum anteriorly like the L vagus nerve -travels to the posterior mediastinum posterior to the root of the R lung -R recurrent laryngeal nerve branches off, and wraps around the R subclavian to ascend back to the larynx ---it travels lateral to the azygous venous system
where does all the lymph from posterior + anterior aspects of axilla (Respectively) collect first?
-all lymph from posterior aspect of axilla (aka scapula) collects in subscapular nodes -all lymph from anterior aspect of axilla (under pec) and around 3/4 of all lymph from breast tissue drains --> pectoral nodes
teres minor: location, tendon, innervation, action
-also forms lower part of posterior aspect of rotator cuff along w/infraspinatus -tendon forms posterior cuff as well -innervated by axillary nerve -externally/laterally rotates shoulder
types of humeral dislocations
-anterior dislocation = ~90% of all dislocations -posterior dislocation = when there's severe trauma like a MVC -inferior dislocation = most severe when your shoulder drops out + gets stuck ---this = very severe b/c important blood vessels + axillary nerve = below so if you pinch/sever them d/t this dislocation, it ==> avascular necrosis which requires a shoulder replacement
what are the terminal branches of the anterior divisions of brachial plexus?
-anterior divisions of brachial plexus ==> musculocutaneous, median, and ulnar nerves --these nerves form an "M" shape anterior to axillary artery which is their characteristic shape
What do the anterior + posterior intercostal aa. branch from?
-anterior intercostal aa branch from internal thoracic artery (small branch of subclavian artery) -posterior intercostal aa branch directly from thoracic aorta ---these = major b/c they supply most of the thoracic wall so ONLY these are found in the costal groove -NOTE that the anterior + posterior intercostal aa form a collateral network therefore they have overlapping territories, which provides redundancy in case of a failure
what do the anterior + posterior intercostal veins drain into?
-anterior intercostal veins drain into internal thoracic vein -posterior intercostal veins drain into azygous venous system
parts of the scapula
-anterior part of scapula ---inside of scapula = bowed inwards and known as subscapular fossa ---bony projection coming off the scapula = acromion (articulates to clavicle) ---small projection pointing forward = coracoid (Btw pecs + humerus) -posterior view of scapula ---scapular spine (becomes acromion on anterior surface) which divides posterior surface into the supraspinous + infraspinous fossa
what is the anterior portion of the elbow called and why is it important?
-anterior portion of elbow = "cubital fossa" - this = the crease where stethoscope = placed for BP measurement
how can you differentiate btw the pulmonic + aortic semilunar valves?
-aortic semilunar valve has the coronary arteries which come off of the aorta AND it also has coronary sinuses - flaps/spaces btw semilunar cusp + aortic wall
What 2 nodes finally drain into what node which drains into the veins where lymph gets recycled in body and even removed?
-apical + supraclavicular nodes drain into subclavian lymph which drains into the veins where lymph = recycled and even removed
what separates the atria + ventricles and why?
-atria + ventricles = separated by valves to prevent backflow of blood
serratus anterior: location, innervation, actions
-attached to inside of medial border of scapula and goes out to ribs -innervated by long thoracic nerve (from ventral rami of C5, C6, and C7) -3 actions: ---holds scapula against thoracic wall ---upward/lateral rotation of whole scapula so that we can lift our arms above our head ---protracts scapula which increases reach (aka boxer muscle)
effect of axillary nerve injury
-axillary nerve innervates deltoid and teres minor so injury ==> inability to fully ABDuct arm and impaired lateral rotation (tho infraspinatus has same fxn and is intact)
how do the spinal cords exit the vertebra?
-before C7, spinal nerves exit ABOVE the vertebra for which they're named -after C7, spinal nerves (beginning w/C8) go below the vertebra
posterior circumflex humeral artery and why is it important
-bigger than the anterior circumflex humeral a and is usually bigger; supplying most of the deltoid + bone including the head of the humerus ---important b/c posterior circumflex humeral a travels w/axillary nerve around the surgical neck of the humerus so a surgical humeral neck fx can ==> avascular necrosis of humeral head which requires shoulder joint replacement
brachial artery - continuation + descent + importance?
-brachial artery = continuation of axillary artery after armpit -descends w/the median nerve thru the arm -important b/c palpable btw biceps + triceps and this = the artery that's compressed w/BP cuff
brachialis: location, fxn
-brachialis = from mid-shaft of humerus to ulna -flexes the elbow
what are the 4 muscles of the superficial layer of the posterior forearm?
-brachioradialis = from humerus to distal radius ---mostly helps flex the elbow (but can pronate/supinate slightly) -extensor carpi radialis longus + brevis = on the radius/lateral side ---extensors + ABDuctors of wrist -extensor carpi ulnaris = on ulnar/medial side ---extensor + adductor of wrist -extensor digitorum ---they extend the wrist BUT their main fxn = to extend digits 2-5
What's the bump on the dorsal root known as and what does it contain?
-bump on the dorsal root = known as the "dorsal root ganglion" (DRG) which houses the cell bodies of sensory neurons (pseudounipolar neurons)
what kinds of artifacts/impressions can the embalming process cause?
-cardiac impressions where the heart sits - much larger on L than R side -on R lung, above the cardiac impression you have the superior vena cava (and therefore the R brachiocephalic vein) and above the hilar region, you have the arch of the azygous venous system (which, remember, travels thru the posterior mediastinum and then dumps into the superior vena cava) -3 grooves on L lung ---large groove for descending aorta ---small groove for esophagus (tho mostly on R side) ---groove for the L subclavian artery
where is the cardiac plexus located?
-cardiac plexus = posterior to heart, pulm trunk + aorta but anterior to tracheal bifurcation
where do the cardiac plexus fibers travel to?
-cardiac plexus fibers extend along the coronary arteries (coming off the ascending aorta) to get to the various parts of the heart it has to innervate ---note that the majority of fibers go to the SA node aka our pacemaker
what are the 2 main structures forming the carpal tunnel?
-carpal bones make up the floor + walls -on anterior surface, there's the flexor retinaculum/transverse carpal ligament which is a thin stretch of CT
painful arc syndrome
-caused by bursitis; when it's very painful to abduct arm btw 50-130 degrees which = mostly the responsibility of deltoid
where do the central nodes drain?
-central nodes drain into the apical nodes (at the apex/top of axilla)
what are the 3 main superficial veins
-cephalic vein - travels along anterolateral forearm + arm ---tributary of axillary vein thru deltopectoral triangle therefore key landmark for subclavian a./v. access -basilic vein - runs on medial aspect of upper limb, crossing over cubital fossa and draining into the brachial/axillary veins -median cubital vein = (network of) connection(s) in superficial cubital fossa ---common site for blood withdrawal
what kind of symp ganglia = found in the cervical, abd, and pelvic regions?
-cervical region: superior, middle, and inferior/stellate cervical ganglia -abd region: lumbar pre- + para-vertebral ganglia -pelvic region: sacral paravertebral ganglia
median nerve spinal levels + fxn?
-connected to ALL levels of spinal cord and provides: ---motor fxn to (remaining) 6.5 muscles of anterior forearm + thenar/thumb muscles ---sensory fxn to lateral 2/3 of palm, palmar side of lateral 3.5 digits + their nail beds
what arteries supply the heart w/blood?
-coronary arteries supply the heart w/blood - the R + L coronary arteries = the main coronary arteries which have branches that supply the muscles
What 3 veins does the coronary sinus receive blood from?
-coronary sinus receives blood from: ---great cardiac vein which starts on anterior surface and travels w/anterior interventricular artery + parts of circumflex artery (basically parts of the LCA) ---middle cardiac vein + posterior interventricular veins BOTH of which drain blood from PIA ---small cardiac vein drains the area supplied by R marginal arteries
what's the most inferior part of the pleural cavity and why is it important?
-costodiaphragmatic recess = most inferior + typically posterior part of the pleural cavity - it's a collection pt for pleural fluid so important in pathology (Ex: trauma to ribcage can ==> blood accumulation which has to be drained using a chest tube OR infected fluid can collect here)
what are the 2 sections shown in the cross-section of the spinal cord and what do they contain?
-cross-section of spinal cord shows a gray matter core surrounded by white matter ---gray matter = neuronal cell bodies ---white matter = neuronal axons covered w/myelin sheath
teres major: location, innervation, and action
-cylindrical muscle attaching scapula to anterior humerus -innervated by lower subscapular nerve (3rd side branch off of posterior cord) -3 actions: to assist latissimus dorsi in all actions (extension, adduction, and internal/medial rotation of shoulder)
What innervates the diaphragm?
-diaphragm = innervated by phrenic nerves which originate from C3-C5 in the neck and provide BOTH sensory + motor innervation to the diaphragm
Why does the diaphragm have hiatuses/openings and how many are there?
-diaphragm has 3 hiatuses/openings b/c structures like blood supply still need to be able to pass btw the thorax + abdomen
what is the back supplied by?
-dorsal rami of spinal nerves
branches directly from ventral rami?
-dorsal scapular nerve innervates levator scapulae & rhomboid major + minor (this = C5) -long thoracic nerves innervate serratus anterior (this = from C5, C6, and C7)
what are the 2 structures supporting valves?
-each valve = supported by a fibrous ring + coronet ---fibrous rings outline the valves and are important for keeping things in proper order + insulating elec stimuli from getting too far too quickly ---coronets = btw ventricles + the great vessels
L vagus pathway
-enters the superior mediastinum anteriorly btw the L subclavian + L common carotid arteries -travels to the posterior mediastinum lateral to the descending aorta -L recurrent laryngeal nerve branches from the vagus nerve and hooks around the aortic arch before traveling superiorly to the larynx
what are the epicondyles of the humerus and why are they important?
-epicondyles of humerus = the bumps on the sides of the elbow -important b/c that's where the flexor + extensor muscles attach
what ligaments stabilize the elbow?
-extracapsular ligaments stabilize the joint - spec the ulnar collateral ligament (UCL) and the radial collateral ligament (RCL) stabilize the humeroulnar joint
internal intercostal muscles - fibers & action?
-fibers travel away from midline (lateral --> medial moving upwards) -works w/innermost intercostal muscles to help w/expiration (Breathing out) - they compress/shrink the chest wall to expel air
external intercostal muscles - fibers & action?
-fibers travel toward midline (lateral --> medial moving downwards like putting your hands in your pocket) -external intercostal muscles help w/inspiration/breathing in - they expand the chest wall to allow more air to flow in
what are the layers of the pericardium?
-fibrous pericardium = the outermost layer made of tough, fibrous CT that's continuous w/the parietal serous layer underneath -the 2 serous layers - parietal + visceral (which = in direct contact w/the heart) are below the fibrous pericardium and are continuous w/each other despite the pericardial cavity in btw ---note that the pericardial cavity = filled w/serous fluid to reduce friction b/c the heart = constantly pumping
what is the muscle in the intermediate layer of the anterior forearm, its actions, and what is it innervated by?
-flexor digitorum superficialis (FDS) = innervated by median nerve; it helps flex the wrist + PIPs of digits 2-5
flexors vs extensor muscles and what conditions can they lead to?
-flexors attach on ulnar side/medially and can ==> golfer's elbow (remember g comes after f so golfer's elbow = related to flexors) -extensors attach on radial side/laterally and can ==> tennis elbow
pec major: location, innervation, actions
-giant sheet of muscle on front part of chest from humerus to clavicle, sternum + ribs -innervated by lateral + medial pectoral nerves (side branches off of lateral + medial cords) -3 actions: ---flexes arm at shoulder ---adducts arm ---internal/medially rotates arm at shoulder
latissimus dorsi: location, innervation, actions
-giant superficial back muscle connecting anterior humerus to dorsal aspect of thorax + lumbar region -innervated by thoracodorsal nerve (2nd side branch off the posterior cord) -3 actions (aka handcuff muscles) ---adducts shoulder ---extends shoulder ---medially/internally rotates arm
diff grades of injury in a separated shoulder
-grade 1 = small tear in AC -grade 2 = mostly torn so stretching CC joint -grade 3 = when AC is completely torn and CC is also torn
how many and what sections can gray matter be divided into?
-gray matter can be divided into 2 sections: ---dorsal/posterior horn which receives sensory info from periphery ---ventral/anterior horn which = mostly made up of large motor neurons that send info --> periphery
common aspects of rib anatomy
-head = the most medial + proximal part w/2 facets which connect to the vertebral bodies -tubercle = right past the neck w/the articular facet that attaches to the transverse process of the thoracic vertebrae -costal groove = a groove w/in the bone where the intercostal nerves + blood vessels travel thru + wrap around the thoracic wall
what sensations does the heart feel and not feel?
-heart = INsensitive to touch, cutting/piercing, and temp - it ONLY senses a lack of O2 (aka ischemia) w/in the myocardium (this = why a MI hurts)
what is the heart and what does each side pump blood to?
-heart = a double sided muscular pump composed of 4 chambers: 2 atria + 2 ventricles ---R side pumps blood to lungs ---L side pumps blood to rest of body
where is the heart located and what is it encased in?
-heart = in the middle mediastinum (posterior to sternum), encased in the pericardial sac
how is heart dominance defined?
-heart dominance = defined by whether the R/L coronary artery ==> posterior interventricular artery (PIA)/posterior descending artery (PDA)
what's the hilar region?
-hilar region = the area that contains the root of the lung and the hilar lymph node
what's "hitting the funny bone"?
-hitting the ulnar nerve (which passes on the groove next to the epicondyle on the humerus)
parts of humerus
-humeral head = smooth area that articulates w/scapula to create shoulder joint -surgical neck of humerus = thin part that's a common fx site -supracondylar region = flaring out of humerus which = also a common fx site -epicondyles = the 2 bumps on the sides of elbow (medial + lateral) -condyles articulate w/ulna to create true elbow joint
where does all the lymph from the upper limbs first collect?
-humeral nodes
What 3 nodes drain into what node in the center of axilla?
-humeral, subscapular and pectoral nodes ALL drain --> central node in center of axilla
position of radius to ulna in anatomical pronation vs pronated position
-in anatomical position, radius = completely lateral to ulna --NOTE that the head of the radius is ALWAYS lateral to the ulna but in pronation, the distal radius moves over the ulna to become medial
what's important to note about the annular ligament in kids?
-in kids, this annular ligament is still slightly loose and b/c the radial head is not fully developed, it can pop out of the socket --the biceps reacts to this by pulling up on the radial tuberosity so sometimes the joint goes back in place automatically OR it pops out to the side, forming a bump on the lateral side of elbow ----b/c this is NOT a true dislocation, it's known as a "subluxation" or "pulled elbow"
major branches of brachial artery
-in the arm, the brachial artery branches off --> deep brachial a. which travels w/radial n. to go to the posterior arm -when brachial artery splits at elbow, it ==> radial a. (travels along the radius) + ulnar a. (travels along ulna)
what are the effects of increased symp innervation?
-increased symp innervation ==> increased heart rate, impulse conduction, contraction force and blood flow thru coronary arteries (b/c fight vs flight response)
What is the inferior mediastinum divided into?
-inferior mediastinum = divided into anterior, middle, and posterior regions
inferior mediastinum divisions and their locations?
-inferior mediastinum = divided into anterior, middle, and posterior regions ---anterior region = immediately behind the sternum ---middle region = the pericardial sac + its contents ---posterior region = behind the pericardial sac + in front of the thoracic vertebral bodies
what does the axilla contain
-infraclavicular brachial plexus structures -axillary artery + associated branches (remember axillary artery = extension of subclavian artery) -axillary veins + associated tributaries -axillary lymph nodes draining upper limb + most breast tissue
what are the intercostal nerves? and their names?
-intercostal nerves = the ventral rami of thoracic spinal nerves -12th thoracic spinal nerve = "subcostal nerve"
what do the intercostal nerves supply?
-intercostal nerves supply intercostal muscles AND our skin - they have lateral + anterior cutaneous branches which pop thru the thoracic wall and supply skin + subcutaneous tissue
what are the intercostal spaces filled with?
-intercostal spaces = filled w/intercostal muscles, membranes, arteries, veins and nerves ---there are 3 layers of intercostal muscles: external, internal and innermost ---intercostal membrane = a fascial membrane ---there are anterior + posterior intercostal arteries + veins
intercostal spaces - location, number, names?
-intercostal spaces = located btw the ribs but are hidden by the muscles of the upper limb + back (ex: pec major + minor, serratus anterior) -there are a total of 11 intercostal spaces, each named for the rib superior to the space BUT note that the space inferior to rib 12 = "subcostal space"
what are the intrinsic muscles and what are they innervated by?
-intrinsic muscles = associated w/digits 2-5 ---they help abd/adduct the fingers, flex the MCPs, flex + extend the PIPs + DIPs ---ALL innervated by ulnar nerve
why is the symp trunk important?
-it innervates ALL of our viscera and its fibers join up w/the plexuses surrounding the esophagus, root of lung, heart and aorta
what are the joints btw our phalanges and what kind of actions do they allow?
-joints btw our phalanges = interphalangeal joints (IPs) - these ONLY allow for flexion/extension --digit 1/thumb ONLY has 1 IP but digits 2-5 have PIPs + DIPs
carpometacarpal joints (CMCs)
-joints btw the carpals + metacarpals; note that the 1st CMC joint = the saddle joint which allows our thumbs to oppose
trapezius: location, innervation, actions
-large broad muscle which attaches scapula to dorsal aspect of neck + thorax -innervated by CN XI/spinal accessory nerve -3 actions: ---elevates scapula (superior fibers) ---retracts scapula (horizontal fibers) ---depresses scapula (inferior fibers)
what's a unique feature of the L lung?
-lingula = a unique feature of L lung and it's a small extension of lung tissue that wraps around anterior surface of heart
triceps brachi: location, action
-long head attaches to scapula (infraglenoid tubercle), lateral head attaches to proximal 1/2 of humerus, medial head attaches to distal 1/2 of humerus -ALL 3 heads attach to olecranon process of ulna -extension of elbow
biceps: location, fxn
-long head goes up, over and thru shoulder joint to scapula; short head attaches to coracoid process -BOTH attach to radial tuberosity + bicipital aponeurosis -flexes elbow + supinates forearm
how does lung tissue get oxygen + nutrients?
-lung tissues get oxygen + nutrients via bronchial arteries which typically come from descending thoracic aorta OR intercostal arteries -bronchial arteries = found in the hilum b/c they enter at the root of the lung and follow the bronchi to get to the lungs
lymphatics
-lymphatics return fluid that's leaked out of the CV system (and into the interstitium) BACK to the heart
what do the main bronchi divide into (all the way)?
-main bronchi divide into secondary/lobular bronchi (3 in R lung, 2 in L lung b/c each lobular bronchi goes to 1 lobe) -secondary/lobular bronchi divide into tertiary/segmental bronchi which serve individual segments of the lobe
what do the majority of ribs attach to and why?
-majority of ribs attach to 2 vertebral bodies at the same time b/c there are 2 articulating facets (one each on the superior + inferior portions of the ribs) which articulate w/2 vertebral bodies at the same time - inferior articulating demifacet of 1 rib will attach to the superior articulating facet
sternum has 3 diff regions - names + what they contain?
-manubrium = most superior region so it attaches to the clavicle & has a jugular notch which = medial to the 2 clavicular notches ---jugular notch = opening for the jugular vein, carotid arteries...etc thru the superior thoracic aperture/thoracic outlet -sternal body = middle portion where most ribs attach to -xiphoid process = most inferior part of sternum ---below the sternum, you have the inferior thoracic aperture
what nerves provide forearm sensation?
-medial cutaneous n. of forearm = from medial cord of brachial plexus and it supplies the medial part of forearm -lateral cutaneous n. of forearm = terminal branch of musculocutaneous n. (which provides motor fxn to upper arm) that provides sensory fxn in forearm -radial nerve has many branches innervating thin strip of posterior forearm + dorsum of hand
side branches of medial cord?
-medial pectoral nerve which innervates pec minor (motor fxn) and pierces thru it to innervate pec major (Medial cord means innervating both pec Minor and pec Major) -2 purely sensory fibers --medial cutaneous nerve of arm + forearm (arm = ONLY T1 while forearm = both C8 & T1)
what are the 4 borders of the axilla?
-medial wall = upper ribs, some intercostal muscles + serratus anterior muscle -lateral wall = humerus -posterior wall = scapula, subscapularis and insertion of latissimus dorsi -anterior wall = pec major + minor
can median nerve be injured? if so, how?
-median nerve can be injured d/t: --supracondylar fx/penetrating trauma ==> severely impaired ability to flex wrist, inability to pronate forearm and oppose thumb; loss of sensation from lateral 3 1/2 digits + their nailbeds AND lateral 2/3 of palm ==> "Hand of Benediction: where pt presents w/only digits 4 and 5 flexing when trying to make a fist and thumb = adducted + extended --proximal forearm injury ==> inability to oppose thumb; loss of sensation from lateral 2/3 of palm and lateral 3 1/2 digits + their nailbeds aka "acute carpal tunnel syndrome" --carpal tunnel injury - remember carpal tunnel has tendons from FDP, FDS and flexor pollicis longus tendon which require synovial fluid to not get inflamed; if this nerve = compressed w/in carpal tunnel ==> inability to oppose thumb and these muscles can atrophy leading to pain, paresthesia and numbness in lateral 3 1/2 digits + their nailbeds
is the mediastinum mobile and why is that important?
-mediastinum = very mobile - important B/C things change in size (ex: heart + lungs change when breathing)
what are our knuckles called?
-metacarpophalangeal joints (MCPs) b/c they're btw the metacarpals + phalanges
why are midshaft humeral fx's dangerous?
-midshaft humeral fx = dangerous b/c it puts the radial nerve and deep brachial a. at risk
most nerves are responsible for 1 component - identify them?
-musculocutaneous nerve innervates anterior part of arm -axillary nerve innervates shoulder -median nerve = most muscles in anterior forearm + thumb muscles -radial nerve = entire posterior upper limb (arm + forearm) -ulnar nerve = slight muscles in anterior forearm + remaining muscles in hand
terminal branches of lateral cord?
-musculocutaneous nerve which innervates anterior compartment of arm - BOTH sensory + motor fxn (levels C5-C7) -also lateral part of median nerve which supplies C5-C7 components to median nerve
conducting airway pathway
-nasal cavity --> nasopharynx --> oropharynx --> laryngopharynx --> larynx --> trachea --> bronchi (primary, secondary, and tertiary) (everything from trachea = part of lower respiratory tract; WHILE everything above = upper respiratory tract)
what fibers carry the ischemic sensation and what path do they take?
-nerves carrying these GVA fibers/sensation follow the symp pathway back to the same level therefore T1-5 in spinal cord b/c that's where the symp fibers originated from
normally, which side is our heart more dominant towards in our thorax and what's the name of the condition where heart orientation = flipped?
-our heart = more L-dominant in our thorax UNLESS you have dextrocardia where heart = in opp orientation (therefore toward the R side)
carpal tunnel syndrome?
-overuse of carpal tunnel which can cause tendinitis/swelling that can compress the median nerve ==> pain in digits 1-3 + weakness in thumb
importance of palmar arches?
-palmar arches provide ALL blood supply to hand and both arches anastomose w/each other to provide complete collateral blood flow to the hand (Ex: can perform allen's test to see if there's enough anastomosing blood flow/perfusion to harvest the radial artery to use for CABG)
effects of increased parasymp stimulation?
-parasymp NS = rest + digest so opp of symp NS b/c goal = to save energy so increased stimulation ==> decreased heart rate, contraction force and vasoconstriction of coronary arteries
where are parasymp + symp postganglionic/postsynaptic fibers found?
-parasymp postganglionic fibers = w/in the walls of the organs themselves -symp postganglionic fibers = in the paravertebral (lateral to vertebrae) + prevertebral (anterior to vertebrae) ganglia
what is the paravertebral/sympathetic trunk?
-paravertebral/symp trunk = a series of communicating rami, cords and ganglia which have fibers connecting each other + talking to the peripheral nerves
innervation of the parietal + visceral pleura
-parietal pleura = innervated by 2 diff nerves ---portion by the ribs/lateral part = innervated by the intercostal nerves ---portion closer to medial diaphragm + mediastinum = innervated by phrenic nerve -visceral pleura = innervated by vagus nerve
2 main components of the L atrium?
-pectinate muscles located in the L auricle ---note that there are fewer pectinate muscles significantly than in the R atrium so it's very smooth unless you open up the auricle; rarely has a depression from fossa ovalis -4 valveless openings for the pulm veins (superior + inferior on BOTH sides)
locations of the phrenic vs vagus nerve?
-phrenic nerve = ANTERIOR to the pulm artery while Vagus nerve = POSTERIOR to the root of the lung
what nerve innervates the pericardial sac and where does that pain go?
-phrenic nerve innervates pericardial sac so if that's involved, pain follows the phrenic nerves to levels C3-C5 (==> pain in the neck)
parietal vs visceral pleura of the pleural cavities?
-pleural cavities = lining which lines the thoracic wall, mediastinum and external portion of lungs so it's broken up into a parietal + visceral pleura --parietal means it's in contact w/the body and there are 4 distinct regions: --- mediastinal portion = in contact w/mediastinum ---costal portion = in contact w/ribs ---diaphragmatic portion = in contact w/diaphragm ---cervical portion = in the root of the neck (b/c the apex of our lungs extends OUT of the superior thoracic aperture) --visceral pleura = most external layer of cells on the actual lungs
what's a plexus?
-plexus = a web of neuronal axons surrounding organs
describe the orientation/order of the vessels from superior to inferior?
-posterior intercostal vv = most superior -posterior intercostal aa -intercostal nerves = most inferior (innermost intercostal muscles form a "tunnel" for the intercostal nerves to travel thru)
where are the postganglionic parasymp fibers lcoated?
-postganglionic parasymp fibers = found w/in wall of heart SPEC the interatrial septum adjacent to our SA + AV nodes (b/c these = what they end up synapsing on)
where are postganglionic symp cell bodies found?
-postganglionic symp cell bodies = found in paravertebral + prevertebral ganglia
where are the postganglionic symp fibers located?
-postganglionic symp fibers = in the symp trunk/paravertebral ganglia + cervical ganglia - these end in the SA + AV nodes
what are postganglionic/postsynaptic fibers?
-postganglionic/postsynaptic fibers = neurons receiving synaptic information from preganglionic cells that then synapse onto/cause action in an organ
where are the pre and postganglionic cell bodies of the symp trunk found?
-preganglionic cell bodies = found in spinal cord levels T1-L2/3 aka the intermediolateral cell column -postganglionic cell bodies = found in paravertebral + prevertebral ganglion and go to the viscera
in which parts of the spinal cord are symp preganglionic cell bodies found?
-preganglionic cell bodies of symp NS = found only in T1-L2/3 part of spinal cord aka the "intermediolateral cell column" (IMLCC)
where are the preganglionic fibers + bodies of the parasymp NS found?
-preganglionic fibers + bodies of parasymp NS = from CNS (spec the brainstem) + sacral portion of spinal cord
where do the preganglionic symp fibers originate from and where do they go?
-preganglionic fibers originate from T1-T5 spinal nerves and they enter the symp trunk in the superior mediastinum ---some synapse at ganglion of SAME spinal cord level and immediately go to heart ---some ascend to cervical ganglia, synapse there and then return back down to heart
what are preganglionic/presynaptic fibers?
-preganglionic/presynaptic fibers = neuronal cell bodies + axons that synapse on other autonomic structures
what are the 3 muscles in the deep layer of the anterior forearm and what are they innervated by?
-pronator quadratus - pronates forearm at distal radioulnar joint (while pronator teres in superficial layer allows for pronation at proximal radioulnar joint) ---innervated by median nerve -flexor digitorum profundus (FDP) = similar to FDS b/c it allows for flexion of wrist, PIPs of digits 2-5 BUT ALSO flexion of DIPs of digits 2-5 ---lateral/radial half is innervated by median nerve (tendons to digits 2-3) ---medial/ulnar half is innervated by ulnar nerve (tendons to digits 4-5) -flexor pollicis longus - flexes the thumb ---innervated by median nerve
what are the 4 muscles in the superficial layer of the anterior forearm & what are they innervated by?
-pronator teres - pronates forearm -flexor carpi radialis = wrist flexor + ABDuctor -palmaris longus = long muscle that goes thru the palm - pretty worthless and absent in around 15% of the population -flexor carpi ulnaris = wrist flexor + adductor ---this = the ONLY muscle which = innervated by the ulnar nerve b/c the rest of the muscles = innervated by the median nerve going thru the middle of the forearm
gen somatic efferent (GSE) fibers
-provide conscious motor fxn to skeletal muscles (ex: GSE = used to tell your muscles to extend your arm to grab something)
gen visceral efferent (GVE) fibers
-provide unconscious motor fxn to organs (ex: cardiac muscle in heart; smooth muscle of intestines, stomach, ureter, and blood vessels)
what is the root of the lung comprised of?
-pulm arteries (Taking deoxygenated blood --> lungs) which have nice, round lumens -pulm veins (returning newly oxygenated blood to heart) which are floppy -main bronchi bringing air into/out of lungs
what are the pulm cavities lined by?
-pulm cavities housing the lungs are lined w/pleura - membranes forming a cavity in btw the 2 layers of them
what are lobes separated by?
-pulm lobes = separated by fissures ---oblique fissure separates superior + inferior lobes on BOTH sides ---horiz fissure = ONLY on R lung b/c it separates the superior + middle lobes
pulm plexus & the types of innervations + nerves providing that innervation
-pulm plexus branches into the R + L lungs following the bronchi -the pulm plexus provides parasymp, symp and visceral afferent/sensory fibers ---parasymp = d/t Vagus nerve/CN X ---symp = d/t symp trunk/chain ---visceral afferent fibers depends
what are the 2 semilunar valves and what are they btw?
-pulmonary/pulmonic semilunar valve btw R ventricle + pulm trunk -aortic semilunar valve btw L ventricle + ascending aorta
What do the radial + ulnar artery terminate as?
-radial artery terminates as DEEP palmar arch in hand while ulnar artery terminates as SUPERFICIAL palmar arch in hand
terminal branches of posterior cord?
-radial nerve innervates ALL posterior upper limb (Triceps + 11 posterior forearm muscles) ---in the forearm, radial nerve splits into a deep + superficial nerve which provide all motor + all sensory fxn to back of hand respectively (think superficial = sensory b/c on top so feeling/sensing things) -axial nerve provides motor fxn to deltoids + teres minor (rotator cuff muscle) & sensory fxn to skin of upper lateral arm ---ONLY has fibers from upper trunk (C5, C6) despite branching off of the posterior cord
rami communicans - the 2 types and what they contain?
-rami communicans = classified as white/gray ---white ramus communicans = PREganglionic fibers entering the chain ---gray ramus communicans = POSTganglionic fibers exiting the chain
major branches of axillary artery
-remember, axillary artery = continuation of subclavian a. after passing the clavicle -2 major branches of axillary artery: ---anterior circumflex humeral artery which goes around the humerus and anastomoses w/the posterior circumflex humeral artery ---subscapular a. goes below scapula and anastomoses w/branches from the subclavian artery
what's unique about rib 1
-rib 1 has special grooves for large vessels like the subclavian a. + v. (as they enter/exit the superior thoracic aperture) -in btw the 2 grooves for the subclavian a. + v., there's the scalene tubercle - the attachment pt for the scalene muscles which attach to the first rib and aid respiration by bringing the rib up + expanding the thoracic cavity for respiration
what's unique about rib 2
-rib 2 has a special tuberosity for serratus anterior
what's unique about ribs 10-12
-ribs 10-12 DON'T have a neck/tubercle b/c they're NOT attaching to a transverse process/sternum itself
what are considered typical ribs - numbers + features?
-ribs 3-9 = "typical ribs" b/c they contain a head, neck, tubercle and articulating facets
in what 2 locations is the brachial plexus located in?
-root of neck -axilla/armpit
what's the different btw ventral/dorsal roots & spinal nerves + rami?
-roots ONLY contain 1 type of fiber (sensory/motor) while spinal nerves + rami contain ALL fibers
What's the name of the (3) structures thru which sensory + motor info pass?
-sensory + motor info have to be combined to get to the same areas therefore: ---outgoing motor fibers leaving the spinal cord immediately form the ventral root and similarly you have the dorsal root ---when these collections of fibers = connected together at a pt, it's known as the "spinal nerve" ---spinal nerves immediately bifurcate --> dorsal + ventral rami
gen somatic afferent (GSA) fibers
-sensory info coming from skin + muscle (Ex: touching a table and identifying it as wood vs metal; cutting your skin and experiencing pain)
what is the pleural cavity filled with and why?
-serous/pleural fluid which help keep the lungs lubricated (important b/c the lungs are always in motion) + inflated (cohesion of lungs to thoracic wall via surface tension) --serous/pleural fluid also creates more neg pressure when breathing in which helps the lungs expand + fill up further
what are the 4 major structures in order of conduction/activation for the conducting system of the heart?
-sinoatrial (SA) node = found w/in R atrium -atrioventricular (AV) node -AV bundle which bifurcates --> R + L bundles -purkinje fibers/subendocardial branches - branch off of the bundles & synapse on the muscles to tell them to contract (think of purkinje cells in cerebellum which have synapses and control motor mvmts)
infraspinatus: location, tendon, innervation, action
-sits in infraspinous fossa below supraspinatus and goes to back of humeral head -tendons forms posterior cuff -innervated by suprascapular nerve just like supraspinatus (Branch of upper trunk) -externally/laterally rotates shoulder
subscapularis: location, tendon, innervation, action
-sits in subscapular fossa on anterior aspect of scapula and goes to anterior part of humeral head -tendon forms the anterior cuff -innervated by upper + lower subscapular nerves (1st + 3rd side branches of posterior cord) -internally/medially rotates shoulder
supraspinatus: location, tendon, innervation, action
-sits in supraspinous fossa and goes over the top of the humerus to attach to it -tendon forms the superior cuff -innervated by suprascapular nerve (branch of upper trunk) -initiates abduction of shoulder (first 15-20 degrees)
distal radioulnar joint
-slightly above the wrist joint but separated by articular cartilage/disk -allows for supination/pronation
pec minor: location, innervation, actions
-small muscle deep to pec major going from coracoid process to ribcage -innervated by medial pectoral nerve -2 actions: ---protracts scapula ---elevates rib(cage) for breathing
glenohumeral joint capsule
-smooth cup area of scapula known as "glenoid fossa" = what articulates w/humeral head to create the shoulder joint -the ligamentous capsule protects this joint cavity and has ligaments, along w/tendons from RCMs + the long head of biceps brachii
what are the 3 types of splanchnic nerves caused by a joining of the symp chain ganglia (and what are they each formed by)?
-sometimes, the preganglionic fibers leaving the symp chain ganglia join together to become: ---greater splanchnic nerve: combos of T5-T9 symp fibers ---lesser splanchnic nerve: combos of T10-T11 ---least splanchnic nerve: T12
what are splanchnic nerves?
-splanchnic nerves = when preganglionic fibers leave symp chain ganglia W/O synapsing and instead synapse onto prevertebral ganglia
What structure do the splanchnic nerves pass thru?
-splanchnic nerves pass thru the diaphragm to provide symp innervation to abd viscera
sprain vs strain
-sprain = injury to ligaments (CT joining two bones together) -sTrain = stretching/minor tearing of a Tendon/muscle
what do all RCMs do?
-stabilize head of humerus in glenohumeral joint during motion --the RC tendons = much more important for stabilization than the ligaments around the glenohumeral capsule b/c ligaments DON'T stretch - they just tear
where does the superficial cardiac plexus travel?
-superficial cardiac plexus travels w/aortic arch in the opp direction so it goes down to the heart
What are the 2 origins of blood supply for the diaphragm?
-superior + inferior phrenic aa = on BOTH R + L sides ---these typically come off of the aorta -venous drainage typically goes to inferior vena cava and then to the heart
superior mediastinum - location/borders
-superior border = superior thoracic aperture while the inferior border = transverse thoracic plane at sternal angle -note that the superior mediastinum = attached to the anterior mediastinum
what are the 3 muscles of the deep layer of the posterior forearm?
-supinator muscle = coming from the ulna ---allows for supination (just like biceps) -abductor pollicis longus = thumb ABDuctor -extensor pollicis longus + brevis = extensor muscles of thumb
describe how we can break the brachial plexus down into parts based on its relationship to the clavicle
-supraclavicular part = in root of neck w/ventral rami, trunks, and divisions -infraclavicular part = in axilla w/cords and terminal branches
can the ulnar nerve be injured and how?
-supracondylar humeral fx/cubital tunnel fx ==> severely impaired fxn of digits 4 + 5; inability to ABD- and add-uct digits 2-5 and loss of sensation from medial 1/3 of hand and medial 1.5 digits leading to ulnar claw -nerve damage at wrist/ulnar tunnel d/t trauma/compression ==> same as elbow injury BUT the clawing aspects of digits 4 + 5 = much worse b/c FDP's ulnar innervation = still present which has lots of resting strength that curls fingers in at rest and NO hand muscles have innervation to extend PIPs/DIPs of digits 4 + 5
branches directly from upper trunk?
-suprascapular nerve provides motor fxn to supra- + infra-spinatus of scapula (rotator cuff muscles) -nerve to subclavius provides motor fxn to subclavius muscle which anchors clavicle to first rib - important b/c clavicle = the ONLY bony connection our entire upper limb has to our bony skeleton
what's the most commonly torn rotator cuff tendon and why?
-supraspinatus tendon, b/c it's the most constricted btw acromion/deltoid and humeral head -can cause a tear d/t Ca2+ deposits OR communication btw bursa + synovial joints can allow for an infection to spread
the 4 RCMs and their tendons
-supraspinatus' tendon = on top/superior -infraspinatus + teres minor's tendons = behind/posterior -subscapularis' tendon = in front/anterior **NOTE that there are NO muscles/tendons underneath
3 places where the humerus = susceptible to fx?
-surgical neck ---important b/c axillary nerve + posterior circumflex humeral artery wrap around surgical neck of humerus so they're at risk in the case of a fx -supracondylar region -midshaft ---important b/c a fx can cause the bone to splinter which can potentially cut the radial nerve ==> loss of downstream innervation of radial nerve so wrist extensors in posterior forearm DON'T have innervation ==> wrist drop
symp NS = found w/in what part of the spinal cord?
-symp NS = found w/in the thoracolumbar portion of spinal cord
what is the symp trunk?
-symp trunk = a series of ganglia w/communicating rami
where is the symp trunk found?
-symp trunk = found in posterior mediastinum or paravertebral trunk
describe the symp trunk extensions
-symp trunk can extend superiorly into the cervical region + inferiorly into the sacrum (to provide symp innervation to our pelvic organs like repro organs, bladder, rectum...etc)
difference btw the atria + ventricles?
-the 2 atria receive blood and have to push blood --> ventricles -the 2 ventricles pump blood AWAY from the heart via the great vessels - pulm trunk + aorta
location of the R + L vagus nerves
-the R + L vagus nerves, found in the superior mediastinum, enter the posterior mediastinum ---they enter the superior mediastinum ANTERIOR to the large blood vessels coming off of the aortic arch BUT when they pass into the posterior mediastinum, they become POSTERIOR to the root of the lung
what ligament goes around the proximal radioulnar joint?
-the annular ligament goes around the circular head of the radius, allowing it to twist in this joint
why is the conducting system of the heart important?
-the conducting system of the heart tells the 4 chambers how to contract in rhythm
where do the coronary arteries originate & how does blood get to the coronary arteries?
-the coronary arteries originate at the coronary/aortic sinuses which = the space behind the triangular flaps of the aortic semilunar valve ---note that blood gets pumped thru aortic valve ==> opening of the flap but when the heart stops contracting, the flaps close and b/c there's no pressure pushing the blood forward, it falls b/c of gravity, causing blood to enter the coronary arteries (d/t a lack of BP effectively)
where do the coronary arteries travel thru?
-the coronary arteries travel w/in the coronary sulcus and are deep to the visceral epicardial layer surrounded by epicardial fat
describe the diaphragm
-the diaphragm has R + L domes or hemidiaphragms which together help form a single structure
lymph node pathways associated w/lung tissue + tracheobronchial tree
-the first to receive lymph = pulmonary nodes and then the hilar nodes (and they continue working their way up the tracheobronchial tree to eventually reach either the R lymphatic/thoracic ducts)
where do the radial nerve + deep brachial artery run thru?
-the groove btw the lateral + medial heads of triceps
on which side of the heart is the muscular wall/myocardium thicker and why?
-the muscular wall/myocardium of L ventricle = 2-3x thicker than the R ventricle b/c it has to push blood thru much of our body (even to head which = against gravity) therefore it has a harder job than the R ventricle
what joint is distal to the elbow but still very nearby?
-the proximal radioulnar joint = btw the radius + ulna (b/c the ulna has the radial notch where the circular head of the radius can swivel) - it allows for pronation/supination
what's the connection of the parietal + visceral pleura?
-the pulmonary ligament (which extends inferiorly)
why do the trunks split into divisions?
-the trunks split b/c the aorta breaks off into the subclavian artery aka the axillary artery aka the brachial artery (based on location) which supplies the upper limbs w/blood --this axillary artery forces the brachial plexus to split into anterior + posterior divisions which go in front of + below the axillary artery -therefore, the cords = named based on their relationship to the axillary artery - lateral, medial, and posterior cords
how many muscles are there in the deep layer of the posterior forearm and what are they innervated by?
-there are 3 muscles in the deep layer of the posterior forearm -remember, all posterior muscles = innervated by radial nerve and in the deep layer, you have the deep radial nerve which provides motor innervation to muscles of posterior forearm
how many types of muscles are there in the superficial layer of the posterior forearm and what is common among all of them?
-there are 4 muscles in the superficial layer of the posterior forearm which ALL share a common tendon at the LATERAL epicondyle of humerus (so overuse can ==> tennis elbow)
what do the 3 tendons of the deep layer of the posterior forearm form?
-they form the anatomical snuffbox so overuse of this area can ==> tendonitis - spec de quervain's syndrome
glenohumeral joint
-this = the shoulder joint b/c it's btw the humerus + glenoid fossa of scapula -this = a ball + socket joint w/lots of motion -surrounded by the ligamentous joint capsule BUT what's really holding it in place = the tendons of the RCMs which form a cuff-like shield over the joint to hold the head in place
coracoacromial ligament
-this ligament = btw coracoid + acromion and it's there b/c a few muscles go thru this area so it acts like a roof to protect those muscles + tendons
thoracic duct - location, drainage, fxn?
-thoracic duct = largest lymphatic vessel in the body which originates in the abdomen (cisterna chyli) and drains into the L brachiocephalic vein -collects lymph from L 1/2 of our thorax, upper limb, head + neck (while the R half of all of these = drained by the R lymphatic duct which drains into the R brachiocephalic vein)
why are thoracic vertebrae easily distinguished?
-thoracic vertebrae = easily distinguished b/c of their inferior oriented spinous processes and b/c they have articulating facets + demifacets for the ribs
what are the 3 components of the R ventricle?
-trabeculae carnae = ridged muscular appearances/muscular portion of ventricular septum -papillary muscles = conical-shaped protrusions of muscle that help close valves ---note that chordae tendineae = the tendinous cords that connect papillary muscles to atrioventricular (AV) valves ---also note that there are 3 types of papillary muscles named for their anatomical positions: ------anterior papillary muscles = the largest so they do the most work in closing the cusps ------posterior papillary muscles = from the posterior part of ventricular wall ------septal papillary muscles = from the interventricular septum (IVS) and are very small so they don't do much -moderator band/septomarginal trabeculae = a bar muscle from IVS to the anterior papillary muscles ---this = very important for coordinating contractions B/C it provides a shortcut for some of the fibers that innervate the heart to reach the anterior papillary muscles (normally fibers that innervate the heart travel thru the IVS and go down to the apex before curving back around to supply innervation)
2 components of the L ventricle?
-trabeculae carneae -papillary muscles + chordae tendineae ---note that there are ONLY 2 papillary muscles - anterior + posterior - b/c only 2 cusps in the bicuspid/mitral valve BUT these papillary muscles = larger b/c they create more pressure than the tricuspid valve
trachea: description + parts
-trachea = a single structure w/C-shaped cartilaginous rings -trachea bifurcates into R + L main bronchi going to the R + L lungs ---carina = a small projection of cartilage at the bifurcation of the trachea ==> 2 main bronchi
gen visceral afferent (GVA) fibers
-transmit pain coming from organs (Ex: stomach aches)
what is the relationship btw the transverse thoracic plane and the mediastinum?
-transverse thoracic plane (imaginary line at sternal angle) separates the mediastinum into superior + inferior parts
Median nerve path
-travels along medial arm w/brachial artery and ONLY innervates forearm after crossing elbow -then it passes thru carpal tunnel to innervate thenar muscles AND give sensation to lateral 3 1/2 digits + their nailbeds --also palmar cutaneous branch = given off before carpal tunnel ==> some sensation of palm
deltoid: location, innervation, action
-triangular muscle divided into 3 parts --anterior fibers flex shoulder --middle fibers control abduction after supraspinatus' initiation (20-120 degrees) --posterior fibers extend shoulder -innervated by axillary nerve
what's the muscle in our posterior arm?
-triceps which = powerful extendor of elbow that attaches to olecranon process
what are the 2 atrioventricular valves and what are they btw?
-tricuspid valve = btw R atrium + R ventricle -bicuspid/mitral valve = btw L atrium + L ventricle
what are the types of visceral innervation and what path do they follow?
-typical pattern = that pain/nociception follows the symp nerves/pathway --reflexive fibers follow parasymp/vagus nerve (b/c vagus nerve goes to brainstem controlling many reflexes + it allows for immediate communication w/brain)
terminal branches of medial cord?
-ulnar nerve (contains C8 & T1) and provides motor fxn to medial 1.5 muscles of anterior forearm and MOSTLY motor fxn to muscles of hand (Except thumb) ---ALSO, ulnar nerve provides sensory fxn to medial 1/3 of palm + dorsum/posterior hand & medial 1.5 fingers (palmar + dorsal sides) -medial part of median nerve which supplies C8, T1 components to median nerve
what nerves provide hand sensation?
-ulnar nerve = palmar/volar + dorsal aspects of digit 5 + medial 1/2 of digit 4 -median nerve = palmar surface of lateral 3 1/2 digits + their nail beds -radial nerve = dorsum of the hand NOT innervated by ulnar + median nn.
ulnar nerve path
-ulnar nerve travels along medial arm, goes behind medial humeral epicondyle and then travels to anterior forearm btw flexor carpi ulnaris + medial 1/2 of FDP (both of which the ulnar nerve innervates) -then ulnar nerve goes above the retinaculum and provides motor innervation to most intrinsic hand muscles and sensory innervation to medial 1/3 of palm + dorsum and medial 1 1/2 digits
coracobrachialis: location, action
-under biceps brachii and attaches to coracoid process + proximal mid-shaft of humerus -flexes + adducts shoulder -is pierced by musculocutaneous nerve
how are the upper limbs divided?
-upper + lower limbs = divided into compartments ---arm = shoulder to elbow w/anterior (biceps + 2 other muscles) and posterior (triceps + 1 muscle) components ---forearm = elbow to wrist w/anterior (8 muscles) + posterior (11 muscles) components ---hand
lateral and medial cords of brachial plexus?
-upper 2 divisions ==> lateral cord w/C5-C7 spinal levels -lowest anterior division becomes medial cord w/C8 & T1 spinal levels -lateral + medial cords combine ==> median nerve that has ALL spinal levels
Causes of axillary nerve injury
-usually d/t fx of surgical neck of humerus
location of vagus vs phrenic nerve in hilum?
-vagus nerve = posterior to root of lungs in hilum WHILE phrenic nerve = anterior to root of lung (think p before v so phrenic nerve = before/in front of/anterior while vagus nerve = behind/posterior)
what are the parasymp preganglionic fibers?
-vagus nerve/CN X
what nerve provides parasymp innervation to majority of body?
-vagus nerve/CN X
what are the 2 fxns of valves?
-valves prevent backflow of blood AND provide some electroinsulation for the conducting system of the heart
what do the ventral rami of the symp NS go out into the thoracic wall w/?
-ventral rami of symp trunk go out into thoracic wall w/our intercostal nerves
what types of fibers do ventral + dorsal roots contain respectively?
-ventral roots ONLY contain efferent motor neurons - GSE + GVE -dorsal roots ONLY contain afferent sensory neurons/fibers - GSA + GVA
ventral vs dorsal roots?
-ventral roots ONLY contain motor fibers -dorsal roots ONLY contain sensory fibers
What can cause lower trunk injuries?
-violent ABDuction of arm (Ex: 1-armed bracing of a fall) -XSive traction on upper limb during delivery
what can damage the ligaments stabilizing the elbow & how are they fixed?
-violent motions like pitching a baseball -Tommy John surgery uses a graft to replace UCL tears
describe the cartilage btw both bones of the glenohumeral joint
-w/in shoulder joint, the cartilage on the inside/cup part of glenoid fossa has some extension cartilage w/a little lip known as the "labrum" and this goes all the way around the shoulder joint
what are the important structures w/in the nasal cavity and what do they do?
-w/in the nasal cavity there are turbinates which are bones (aka conchae) which are covered in mucus tissue that turn the air and slow it down to gain some heat + moisture and to filter out any dust + allow for some olfaction ---BASICALLY, turbinates prepare the air to enter the lungs
what is the continuation of the musculocutaneous nerve?
-when musculocutaneous nerve continues to forearm, it's on the lateral aspect so known as "lateral cutaneous nerve of the forearm"
lymph nodes
-where lymph tissue collects in nodes and carries itself thru little vessels
characteristic features of radius
-wide end = associated w/wrist while circular part = associated w/ulna -radial tuberosity = bump near top of radius which is what biceps attaches to and pulls on to supinate our forearm
What can cause upper trunk injuries?
-wide separation btw head + shoulder --ex: upended fall --ex: XSive traction on neck during delivery
effect of long thoracic nerve injury
-winged scapula where the medial border of scapula (where serratus anterior attaches to) = pushed backward when pushing against a sturdy structure
scientific name for the wrist and why?
-wrist = aka radiocarpal joint b/c it's ONLY btw the radius + proximal carpal bones
how many structures pass thru the carpal tunnel and what are they?
10 structures pass thru the tunnel - tendons from 3 muscles + 1 nerve -4 tendons of FDS (flexes PIPs) -4 tendons of FDP (flexes DIPs) -tendon of flexor pollicis longus -median nerve
phalanges
2-3 bones above the metacarpals for each digit
posterior mediastinal contents
6 components total -descending thoracic aorta -azygous venous system (ALSO in middle mediastinum) -vagus nerve (ALSO in superior mediastinum) & vagal trunks -sympathetic trunk (splanchnic nerves) -esophagus (ALSO in superior mediastinum) -thoracic duct (ALSO in superior mediastinum)
parts of the heart on the external surface & what do they contain/what do they do?
6 pars of the heart on the external surface -apex = the most inferolateral pointed part which points toward the L half of our ribcage + down towards our L hip -base = posterior, comprising MOSTLY of L atrium along w/the pulm veins + a small part of the pulm trunk -diaphragmatic surface = our inferior border MOSTLY made of L ventricle as the heart sits on the diaphragm -R + L atrial auricles = small protrusions/flaps on both atria that provide extra room for the atria to expand w/blood (embryological remnants) -coronary sulcus = division of atria + ventricles that houses the coronary arteries + veins & coronary sinus (this = inferior to the auricles) -epicardial fat = on the surface of the heart and is normal + healthy if not XSive
anterior/superior mediastinal contents from anterior to posterior?
7 components total -thymus gland = important lymph organ that's more active when younger so in older individuals, you only see remnants of the thymus (atrophied glandular tissue w/lots of adipose) -brachiocephalic veins + superior vena cava ---brachiocephalic veins return blood from head + upper limbs to the superior vena cava which = formed from the combo of the 2 brachiocephalic veins (note that the l brachiocephalic v. = longer than the R b/c the superior vena cava = on the R side of the chest) -arch of aorta + roots of its 3 major branches - brachiocephalic trunk, L common carotid artery + L subclavian artery -vagus + phrenic nerves ---NOTE that the R recurrent laryngeal nerve hooks around the R subclavian artery while the l recurrent laryngeal nerve hooks around the aortic arch -trachea/airway -esophagus -thoracic duct
middle mediastinum contents
8 components total -fibrous + serous pericardial layers -heart -superior vena cava (ALSO in anterior/superior mediastinum) -azygous venous system -pulm trunk + arteries (sending deoxygenated blood from heart to lungs for reoxygenation) -pulm veins (returning newly oxygenated blood to heart) -primary bronchi -phrenic nerves (ALSO in anterior/superior mediastinum)
A 38 y/o woman was brought to the ED w/severe pain all around her R arm + shoulder. She states that she slipped on the landing of her staircase and fell hard on her R side. If she has a true separated shoulder, what do you suspect would be the first structure damaged?
Acromioclavicular joint
What nerve travels around the surgical neck of the humerus w/the posterior circumflex humeral artery?
Axillary nerve
Which of the following is NOT considered a subsection of the parietal pleura? A. Mediastinal B. Hilar C. Costal D. Cervical
B. Hilar (the other subsection = diaphragmatic)
A 21 y/o man was brought via ambulance to the ED w/a knife wound to the root of his neck. Given the options below, what structure(s) may have been directly damaged by the knife? A. Lateral Cord B. Upper trunk C. Medial cord D. All of the above E. A & C only
B. Upper trunk
Which of the following is true regarding the lungs? A. They are symmetrical organs B. The L lung possesses an oblique and horiz fissure C. The R lung has 3 lobes while the L has 2 D. The R lung possesses a structure referred to as the lingula
C. The R lung has 3 lobes while the L has 2
Which of the following is true regarding the chambers of the heart? A. The bicuspid valve is found btw the R atrium + ventricle B. The openings for the pulm veins have valves C. The moderator band is found w/in the R ventricle D. The L ventricle has anterior, posterior, and septal papillary muscles
C. The moderator band is found w/in the R ventricle
long thoracic nerve: spinal levels, innervation, fxns
C5-C7; innervates serratus anterior -fxns include: --rotating the whole scapula up so that we can lift our arms above our head --keeping scapula on thoracic wall --protracting scapula or increasing reach by bringing scapula forward along the thoracic wall
During surgery to remove infected lymph nodes in the neck of a 58 y/o woman, the surgeon inadvertently lesioned the middle trunk of the brachial plexus. Fibers from what spinal level were likely affected by the mistake?
C7
Which of the following structures is found in both the superior and posterior mediastinum? A. Trachea B. Superior vena cava C. Main bronchi D. Esophagus
D. Esophagus
What artery supplies blood to the triceps brachii?
Deep brachial artery
If a surgeon decides to use the radial artery to perform a coronary bypass on a pt, what artery would be directly affected?
Deep palmar arch
If I hit my "funny bone" hard enough and for long enough, I may permanently damage some nerve fibers in the ulnar nerve. If that happened, what fxnal loss would be noted?
Difficulty spreading my fingers (abduction)
Which structures will carry pain fibers from the lungs?
Fibers from sympathetic trunk
Which of the following structures articulates with the body of the vertebrae?
Head of the rib
Which artery usually gives rise to the anterior interventricular artery?
Left Coronary Artery (LCA)
Sensation to the medial arm is delivered by what nerve and contains nerve fibers from what spinal levels?
Medial cutaneous n. of the arm; T1
A herniated intervertebral disk at the level of C5 may affect fibers coursing through what nerves?
Median, Axillary (& Musculocutaneous)
What are the 3 hiatuses/openings in the diaphragm?
Mnemonic: I 8 10 Eggs at 12 (noon) -Inferior vena cava at level T8 goes from abd to thorax returning blood -esophageal at level T10 going from thorax to abd -aortic at level T12 going from thorax to abdomen
What innervates the anterior compartment of the arm?
Musculocutaneous nerve
If a person has difficulty flexing their elbow, particularly against resistance, what nerve would you suspect was injured?
Musculocutaneous nerve (b/c biceps?)
What blood vessel does the R recurrent laryngeal nerve hook around as it ascends to the larynx?
R subclavian artery
Cause of radial nerve injuries?
Radial nerve can be injured at diff places ==> diff presentations (remember radial nerve innervates all posterior upper limb) --w/in the axilla, you have Saturday night palsy or the inability to extend forearm (loss of triceps) + wrist/thumb AND loss of sensation in a thin strip across posterior upper limb --midshaft humeral fx affects posterior forearm innervation (triceps = fine) so injuries affect wrist + digit extension at MCPs ==> wrist drop and loss of sensation from dorsolateral hand + proximal lateral 3.5 digits ----same happens w/supracondylar humeral fx
What is the proper order in which electrical impulses travel thru the heart?
SA node --> AV node --> AV Bundles --> Purkinje fibers
While fighting the harsh wind and brutal cold of a winter day, you slipped and to brace your fall, you put out your left hand. You then feel an immense amount of pain around your wrist and lower forearm. After half-hour you notice an incredible swelling at the base of your left thumb in the area of the anatomical snuffbox. What bone do you suspect may have been fractured?
Scaphoid bone
If a person has difficulty shrugging their shoulders, particularly against resistance, what nerve would you suspect was injured?
Spinal accessory nerve
The 2nd rib attaches to the sternum at what structure?
Sternal angle
What artery provides the direct anastomosis w/the deep palmar arch?
Superficial palmar arch
At what vertebral level does the aorta pass thru the diaphragm?
T12
The same surgeon was also performing a lymphectomy in the axilla, when he nicked yet another nerve. Following the procedure, the patient noticed numbness in her pinky and weakness in her hand. What structure was likely affected?
Ulnar nerve
scaphoid & why it's important
a thin bone that's part of the carpal on the thumb/lateral side and closest to the radius -scaphoid = the longest carpal bone and it has a thin middle/waist, making it susceptible to a fx after a FOOSH
AC joint
acromioclavicular joint btw distal clavicle + acromion -only minimal mvmt = permitted - this joint = more stiff to provide stability for entire upper limb -stretching/tearing this ligament (aka a sprain) can cause a separated shoulder
what's generally true of flexion/extension in anatomical position?
any time a joint moves anteriorly, it's flexion while any time it moves posteriorly, that's extension; knee = the opposite and thumb = different
why is the head of humerus esp vulnerable to dislocation when arm = abducted?
b/c of the lack of an inferior tendon cuff
what's the difference btw ball + socket and condyloid joints?
ball and socket joints can do everything; condyloid joints can NOT rotate, but they can do circumduction
brachial a.'s importance around the elbow?
brachial artery sends off may branches that anastomose around the elbow to provide collateral blood flow (even when flexing elbow)
olecranon process
bump at the top of the ulna which is what we consider to be our elbow
what are rami?
connecting axons
CC joint
coracoclavicular joint btw distal clavicle + coracoid process -suspends upper limb (scapula) from clavicle -usually NOT damaged if you have NOT already damaged the AC joint
flexion of digits 2-5
curling fingers up/in
What's the major muscle for respiration?
diaphragm - so the intercostal muscles simply help by moving the rib cage/thoracic wall to create additional space
what is the axilla?
e armpitth
what kind of joint is the elbow and what actions does that allow for?
elbow = hinge joint so ONLY does flexion/extension
ribs 8-10
false ribs b/c their cartilaginous bars DON'T attach directly to sternum - they attach to each other ==> a single cartilaginous bar that then attaches to that of rib 7 (which = attached to sternum b/c it's a true rib)
thumb flexion + extension
flexion = moving thumb closer to fingers while extension = moving thumb away from fingers
What actions are produced at the true elbow/humeroulnar joint?
flexion and extension
what kind of joints are our MCPs and what kinds of action do our MCPs allow for?
flexion/extension, abduction/adduction, and circumduction (NOT rotation) so condyloid joints
what actions does the wrist perform/permit?
flexion/extension, abduction/radial deviation and adduction/ulnar deviation
ribs 11-12
floating ribs b/c they only have cartilaginous nubs and DON'T attach to the sternum in any way
what supplies the heart's autonomic innervation?
heart's autonomic innervation = supplied by cardiac plexus containing symp, parasymp, and GVA fibers
scientific term for elbow and why?
humeroulnar joint b/c radius does NOT participate in true elbow joint (head of radius articulates directly ONLY w/ulna)
bursitis
inflammation/swelling of the bursa from too much overuse
side branch of lateral cord?
lateral pectoral nerve - provides motor innervation to pec major
sternal angle
line of demarcation btw the manubrium + sternal body where the 2nd rib ALWAYS attaches to therefore it's a landmark of the transverse thoracic plane
Effect of lower trunk injuries
lower trunk ==> ulnar, and distal contribution of median nerve --ulnar nerve = responsible for ALL intrinsic muscles of hand which do ABD-/add-uction of digits, flexion of MCPs (digits 2-5), extension of PIPs + DIPs (digits 2-5) therefore injury ==> hyperextension of MCP joints and flexion of PIPs + DIPs (Esp digits 4-5) --median nerve = formed lateral + medial cords and are involved in thenar muscles (flexion, ABDuction and opposition of thumb) so injuries ==> thumb extension aka ape/simian hands -injuries also lead to loss of sensation at medial aspect of forearm BASICALLY, you end up w/Klumpke's palsy/claw hand
where does the majority of deoxygenated blood drain to?
majority of deoxygenated blood = drained eventually into the coronary sinus into the R atrium
abduction of arm at shoulder?
moving arm away from body/midline
adduction of arm
moving arm toward midline of body
extension of wrist
moving hand down
adduction
moving hand toward pinky side aka ulnar deviation
ABDuction
moving hand toward thumb side aka radial deviation
flexion of wrist
moving hand up
circumduction
moving shoulder in a circle w/palms in same direction the whole time
what are all the muscles in anterior arm innervated by?
musculocutaneous nerve
where do the superficial veins begin?
on dorsum of hand
bursa
pads of synovial fluid that allows tendons to move past it w/o friction (spec, we have subacromial + subdeltoid bursae)
If you were to poke the pericardial sac w/a needle, what would be the second layer you pierce?
parietal serous
A 57 y/o man fractured the surgical neck of his left humerus. What artery that travels w/the axillary nerve may have been affected by the fx?
posterior circumflex humeral artery
what's the worst kind of dislocation in SC joint?
posterior dislocation = very bad b/c many important structures = posterior to clavicle so this is a medical emergency
what is all of posterior upper limb innervated by?
radial nerve
what is the entire posterior upper limb innervated by?
radial nerve
what does the thoracic wall consist of
ribs, sternum, and thoracic vertebrae bodies (which form the midline posterior section of thoracic cavity)
scaphoid fx and why is it dangerous
scaphoid fx ==> swelling at the base of the thumb in the anatomical snuffbox -the radial artery initially passes the scaphoid before going back to feed it so a scaphoid fx = dangerous b/c if you fx the middle, the proximal part does not get blood supply ==> avascular necrosis of the scaphoid
What nerve innervates the trapezius & sternocleidomastoid muscles?
spinal accessory nerve
extension of digits 2-5
spreading fingers out
SC joint
sternoclavicular joint btw clavicle + manubrium of sternum -this = the ONLY joint/bony connection btw upper limb + rest of skeletal body -this joint = moveable which = why we can move our scapula forward + back -can be dislocated in the event of trauma
extension of arm
swinging arm backward
flexion of arm
swinging arm forward
metacarpals
the 5 bones above the carpals, each of which goes to a digit
why is the R hemidiaphragm oriented more superiorly?
the R hemidiaphragm has the liver below which pushes up on the R hemidiaphragm whereas the L side has the spleen which takes up less space
which finger technically does not abduct/adduct and why?
the middle finger/3rd digit b/c it's considered the midline and so the other digits abd/adduct in relation to this finger
dermatomes?
the predictive pattern of what spinal nerves = innervating our skin
carpals
the small bones in the wrist
where do preganglionic/presynaptic fibers originate in general and where specifically are parasymp + symp fibers found?
they originate w/in the CNS ---parasymp fibers = found in brainstem or sacral spinal cord ---symp fibers = found in thoracic + lumbar spinal cords
why are the superficial veins important?
this = where blood is taken from during a blood draw
the thoracic cavity is divided into how many regions and what are they?
thoracic cavity = divided into 3 regions: -mediastinum which contains heart, blood vessels, thoracic duct...etc -R + L pulm cavities on either side of mediastinum which contain the lungs + pleural cavities
thumb abduction + adduction
thumb abduction = moving thumb forward (ex: gouging out the eyes of your abductor) while thumb adduction = moving thumb back to hand area
what mvmt is unique to the thumb and what allows for it?
thumb can oppose (extend, abduct, flex, and adduct the thumb) b/c of the unique saddle joint
ribs 1-7
true ribs b/c their costal cartilages extend from ribs and attach directly to sternum
Effect of upper trunk injuries
upper trunk ==> suprascapular, axillary, and musculocutaneous nerves --suprascapular nerve innervates supraspinatus (RCM that initiates ABDuction of arm) + infraspinatus (RCM that allows for external/lateral rotation) therefore injury ==> loss of ABDuction + lateral/external rotation of arm --axillary nerve innervates deltoid (remaining ABDuction of arm) + teres minor (RCM allowing for external/lateral rotation) therefore injury ==> forceful inward/medial rotation aka Erb's/waiter's tip palsy --musculocutaneous nerve innervates entire anterior arm including brachialis (flexion of forearm) and biceps brachii (flexion + supination of forearm) BUT b/c musculocutaneous nerve ALSO has C7 spinal level, there's a severely impaired ability to flex elbow + supinate forearm ---musculocutaneous nerve continues into forearm as lateral cutaneous nerve of forearm so injury ==> diminished sensation of lat aspect of arm, forearm, and thumb BASICALLY, you end up w/Erb's/waiter's tip palsy where pt presents w/pronated forearm that's medially/internally rotated and is largely extended
colles' fx
usually affects the distal radioulnar joint b/c it's d/t a FOOSH -colles' fx = spec a fx in the distal radius (or even ulna depending on severity) causing the distal radius to move forward as compared to the rest of the hand so it's known as the "dinner fork" deformity --sometimes, you can have an avulsion (a piece of bone tearing off of itself)
what's a joint?
when any two bones come together
when is the glenohumeral joint most at risk for being dislocated?
when arm = abducted and something hits it from above
The posterior forearm is responsible for what primary action?
wrist extension
can the long thoracic nerve be injured? if so, how?
yes, can be injured in trauma --axillary tail of breast tissue sits right over long thoracic nerve therefore a radical mastectomy or knife wounds can injure this nerve