NBME review Flashcards
regions of spine with anterior curvature
cervical and lumbar (secondary=devs with sit/stand/walk)
regions of spine with posterior curvature
thoracic and sacral (primary=present at birth)
kyphosis
excessive thoracic curvature = hunchback
lordosis
excessive lumbar curvature = swayback
ligamentum flavum
extends between lamina of adjacent vertebrae
annulus fibrosis
outer part of vertebral disc = fibrous CT
nucleus pulposis
central part of vertebral disc = gel-like
herniated (“slipped”) disc
- annulus fibrosis deteriorates -> nucleus pulposis bulges -> spinal nerve compression
- most common in lumbar and cervical
what space is accessed during a lumbar puncture?
lumbar cistern/dural sac/ thecal sac
fibrous joint (synarthroses)
- little or no movement
* ie sutures of skull
cartilagenous joint (amphiarthroses)
- slight movement
- fibrocartilagenous disks between articular surface
- sternocostal joints, intervertebral joints, and symphysis pubis
intima
cells lining the surface of the synovial membrane that secrete synovial fluid
joint effusion caused by
irritation to the synovial membrane -> excess production of synovial fluid
scapulothoracic “joint”
- ant surface of scapula and post./lat. thoracic wall
* allows elevation/depression, protraction/retraction, and upward/downward rotation of scapula
rotator cuff muscles
- supraspinatus
- infraspinatus
- subscapularis
- teres minor
movement of supraspinatus
initiate and assist ABDUCTING arm
movement of infraspinatus
ER, ABDUCTION, ADDUCTION
movement of subscapularis
IR
movement of teres minor
ER AND ADDUCTION
innervation of supraspinatus
suprascapular nerve
innervation of infraspinatus
suprascapular nerve
innervation of subscapularis
upper and lower subscapular nerve
innervation of teres minor
axillary nerve
muscle most often involved in rotator cuff injury
supraspinatus muscle
muscles of anterior compartment of arm function
- flex arm and forearm
* supinate hand
innervation of anterior compartment of arm
musculucutaneous nerve
supply of anterior compartment of arm
branches of brachial artery
muscles of posterior compartment of arm function
extend the forearm
innervation of posterior compartment of arm
radial neve
supply of posterior compartment of arm
branches of deep brachial artery
annular ligament
- stabilizes head of radius in relation to ulna
* easily injured in children
muscles of anterior compartment of forearm function
- flex wrist and digits
- pronate hand
- flex thumb
- adduct/abduct hand
innervation of anterior compartment of forearm
median nerve, EXCEPT flexor carpi ulnaris and ulnar have of flexor digitorum profundus (ulnar n)
supply of anterior compartment of forearm
branches of radial and ulnar arteries
muscles of posterior compartment of forearm function
- extend wrist and digits
- supinate hand
- extend and abduct thumb
innervation of posterior compartment of forearm
radial nerve
supply of posterior compartment of forearm
branches of radial and ulnar arteries
superficial muscles of hand
- 3 of thenar pad
- 3 of hypothenar pad
- lumbricals
- adductor pollicis
innervation of superficial hand muscles
ulnar nerve EXCEPT lateral 2 lumbricals and 3 thenar muscles (median nerve)
deep muscles of hand
- 3 palmar interossei
* 4 dorsal interossei
innervation of deep muscles of hand
ulnar nerve
supply of hand
branches of radial and ulnar arteries via superficial and deep palmar arches
merocrine secretion
product released by exocytosis (e.g. pancreas)
apocrine secretion
product release with a small portion of apical cytoplasm and membrane (e.g. mammary gland)
holocrine secretion
secretory product constitutes entire cell and its products (e.g. sebaceous gland)
tight junctions (zona occludens)
- localized sealing of plasma membranes of adjacent cells
* important proteins: occludin, claudin, ZO proteins
desmosomes (macula adherens)
- mechanical anchoring -> resist cell-cell separation
- plaque of desmoplakin, plakoglobin, and plakophilin -> cytoplasmic keratin filaments on one side and adhesion molecules on the other
gap junctions
- permit passage of small molecules
* membrane proteins call connexins form connexon
hemidesmosomes
- asymmetrical cell junctions
* links cells to basal lamina by integrin proteins
proximal to distal limb development dependent on
- FGF (fibroblast growth factor)
* mesoderm produce FGF -> ectoderm proliferation (AER) -> AER produces FGF -> prolif. of mesoderm (progress zone)
dorsal to ventral limb development dependent on
- most important gene is Wnt-7a (signaling protein expressed by AER)
- Wnt-7a activates LMX-1 in mesoderm -> form dorsal structures
- ectoderm on ventral side has Engrailed1 that represses Wnt-7a
anterior to posterior limb development depends on
- Shh gene
- cells that produce Shh called ZPA (zone polarizing activity) are found at posterior base of limb buds
- Shh diffuses across limb bud to activate Hox genes that pattern thumb to little finger
**intramembranous ossification
- mesenchyme cells differentiate directly to osteoblasts -> lay down primary/woven bone -> remodeled to lamellar bone
- flat bones of skull and bones of face
**endochondral ossificatiuon
- long bones, vertebral column, pelvis, sternum, skull base
* mesenchyme -> chondroblasts -> cartilage model -> osteoblasts
**reduction defects of limb
- meromelia - part of limb
- amelia - entire limb missing
- phocomelia - meromelia with hands or feet coming off shoulder/hip
- THALIDOMIDE -> disrupts AER and its production of FGF
critical period of limb development
week 4-5
**duplication defects of limb
Shh involved in polydactyly -> If ZPA duplication -> mirroring of digits
**dysplasia defects of limb
ie abnormal fusion of digits (syndactyly) resulting from reduced apoptosis
caudal regression syndrome
(caudal dysplasia)
•impairs dev of lower half of body
•mechanism is abnormal gastrulation -> not enough caudal mesoderm
•genetic and environmental factors implicated
sirenomelia
- “mermaid syndrome”
- extreme rare form of caudal dysplasia
- fusion of lower limbs at midline
period of maximal sensitivity to teratogens
weeks 3-8 -> organogenesis
osteoblast
- derived from osteoprogenitor cells
* cuboidal shaped, found on surface of bone
parathyroid hormone receptor
- expressed on osteoblasts
- stimulated by PTH -> induce RANKL and mCSF expression, inhibits OPG production
- PTH STIMULATES OSTEOCLASTOGENESIS
alkaline phosphatase
- cell surface enzyme found on osteoblasts
* produce phosphate ions in bone matrix synth
IGF-1 receptor
- found on osteoblasts
* binds IGF-1 from liver to stim growth of long bones
major component of osteoid matrix
type I collagen
osteoprotegerin (OPG)
- produced by osteoblast
* decoy receptor for RANKL -> inhibits osteoclastogenesi
RANKL
- found on osteoblast
- ligand for RANK of osteoclast precursors
- receptor for OPG
osteocalcin
metabolic marker of bone formation found in osteoblast
primary/woven bone
initial ECM produced by osteoblast
secondary/lamellar bone
- remodeled woven bone
* organized sheet of collagen
osteocyte
- osteoblasts that have become surrounded by bone matrix and stop producing osteoid
- release factors that stimulate bone remodeling/turnover in response to forces on bone
osteoclast
- large multinucleated cells on surface of bone
* degrade bone matrix
osteoclast derived from
monocyte precursors originating in bone marrow
steps of osteoclastogenesis
monocyte -> macrophage -> binds M-CSF -> expresses RANK -> binds RANKL and becomes osteoclast precursor -> uncouples from osteoblast -> matures with sealing zone and ruffled border
M-CSF produced by
- macrophage colony-stimulating factor
* osteoblasts
denosumab effect on osteoclastogenesis
- decreases osteoclastogenesis
* antibody to RANKL (functions like OPG)
low plasma calcium causes secretion of
PTH -> acts on osteoblast receptors -> differentiation of osteoclasts -> increase bone turnover
high plasma calcium causes secretion of
calcitonin -> activation of osteoclast -> retract from bone surface -> decrease bone turnover
course of median nerve
- from lateral and medial cords
- runs with brachial artery in medial arm
- enters forearm anterior to elbow joint
- enters hand through carpal tunnel
course of ulnar nerve
- from medial cord
- runs with brachial artery in medial arm
- posses posterior to medial epicondyle
- medial aspect of forearm
course of axillary nerve
- from posterior cord
* passes posterior to surgical neck of humerus
course of radial nerve
- from posterior cord
- posterior compartment of arm close to shaft of humerus
- enters forearm posterior to lateral epicondyle
posterior interosseous nerve
deep branch of radial nerve in the forearm
anterior interosseous nerve
deep branch of median nerve in forearm
sensory deficits with axillary nerve lesion
- ie dislocation glenohumeral join, fx surgical neck humerus
* lateral shoulder and upper arm
sensory deficits with radial nerve lesion
- ie midshaft fx humerus
* posterior arm/forearm and dorsum of hand
sensory deficits with median nerve lesion
- supraepicondylar fx of humerus or carpal tunnel syndrome
- palmar aspect of thumb
- palmar and dorsal aspect of index, middle, and half of ring finger
sensory deficits with lesion of anterior interosseous nerve
- ie fx of forearm
* no sensory deficits
sensory deficits with lesion of ulnar nerve
- ie medial epicondyle fx, wrist fx or laceration
* medial aspect of hand and most of 4th and 5th digits
sensory deficits with lesion of musculocutaneous nerve
lateral forearm
upper brachial plexus injury (Erb’s Palsy)
- most commonly involves musculocutanous, axillary, suprascapular
- arm hangs by side, adducted, medially rotated, forearm extended and hand pronated
lower brachial plexus injury (Klumpke’s Palsy)
- most commonly involved ulnar (maybe median)
* “ulnar claw hand” (hyperextension of MP joints and flexion of IP joints)
iliofemoral ligament prevents
- hyperextension of hip joint
* anterior part of joint capsule
pubofemoral ligement prevents
- excessive abduction and hyperextension of hip
* anterior inferior part of joint capsule
ischiofemoral ligament prevents
- hyperextension of hip joint
* posterior part of joint capsule
supply to the hip joint
- medial and later circumflex (around neck of femur)
* medial provides majority
ACL prevents
anterior displacement of tibia on femur
PCL prevents
posterior displacement of tibia on femur
MCL and LCL function
help stabilize knee joint
medial and lateral meniscus function
- help stabilize knee join
* shock absorption
unhappy triad of O’Donahue
MCL, ACL, and medial meniscus when injured together
^most commonly injured knee structures
ankle joint most stable when
dorsiflexed, comped with plantarflexed
ligaments in ankle
- deltoid on medial side
* anterior talofibular, posterior talofibular, and calcaneofibular laterally
ankle sprain normally occurs via
excessive inversion on a plantarflexed weight-bearing foot
ankle ligament most at risk in ankle sprain
anterior talofibular
superficial abductors and extensors of femur (gluteal region)
- gluteus maximus (inferior glut n.)
* gluteus medius, gluteus minimus, and tensor fascia lata (superior glut n.)
deep external rotators of femur (gluteal region)
- piriformis (nerve to the…)
- obturator internus (nerve to the…)
- superior and inferior gamellus (nerve to the ^)
- quadratus femoris (nerve to the…)
anterior compartment of thigh function
extend leg at the knee
innervation of anterior compartment of thight
femoral nerve
supply of anterior compartment of thigh
femoral and deep femoral arteries
medial compartment of thigh function
adduct the thigh at the hip
innervation of medial compartment of thigh
obturator nerve
supply of medial compartment of thigh
deep femoral and obturator arteries
posterior compartment of thigh function
- flex leg at knee
* extend thigh at hip
innervation of posterior compartment of thigh
sciatic nerve
supply of posterior compartment of thigh
deep femoral artery
anterior compartment of leg function
- dorsiflex foot
- invert foot
- extend toes
innervation of anterior compartment of leg
deep fibular nerve
supply of anterior compartment of leg
anterior tibial artery
lateral compartment of leg function
- plantarflex foot
* evert foot
innervation of lateral compartment of leg
superficial fibular nerve
supply of lateral compartment of nerve
fibular artery
posterior compartment of leg function
- plantarflex foot
- invert foot
- flex toes
innervation of posterior compartment of leg
tibial nerve
supply of posterior compartment of leg
posterior tibial artery
major nerves of lumbar plexus
- lateral cutaneous nerve of thigh (L2, L3)
- femoral nerve (L2-L4)
- obturator nerve (L2-L4)
major nerves of sacral plexus
- superior gluteal (L4-S1)
- inferior gluteal (L5-S2)
- sciatic (L4-S3)
- posterior femoral cutaneous (S1-S3)
- named branches to small external rotators
sensory deficits with femoral nerve lesion
- anterior thigh
* medial knee, leg, and foot
sensory deficits with obturator nerve lesion
medial thigh above knee
sensory deficits with superior gluteal nerve lesion
NONE
sensory deficits with tibial nerve lesion
- posterolateral leg
- lateral malleolus
- sole and lateral foot
sensory deficits with superficial fibular nerve lesion
- lateral leg
* dorsum of foot
sensory deficits with deep fibular nerve lesion
•triangular area between 1st and 2nd toes
femoral artery is extension of
external iliac artery as it crosses under inguinal ligament
deep femoral artery branches
from posterolateral aspect of femoral artery in femoral triangle
3 main branches of deep femoral artery
- perforating branches -> medial and posterior thigh
- lateral femoral circumflex
- medial femoral circumflex
femoral artery moves to posterior compartment proximal to knee to become
popliteal artery
genicular arteries
branch off popliteal artery in posterior thigh to supply knee
popliteal artery divides at lower border of popliteal fossa to
anterior tibial and posterior tibial arteries
fibular (peroneal) artery comes from
posterior tibial artery
dorsalis pedis artery extension of
anterior tibial artery
inferior and superior gluteal arteries arise from
internal iliac artery
transverse tubule
finger-like projections formed by invaginations of sarcolemma
function of T-tubule
- in contact with SR
* transmits depolarization from plasma membrane to deep in muscle cells
where is intracellular Ca2+ stored in muscle cells?
SR
*important for regulation of muscle contraction
myofibrils composed of
thick (myosin) and thin (actin) filaments
desmin
- protein that connects myofibrils and is anchored in sarcolemma
- facilitates coordinated contraction
Z-line/disk
- define boundaries of sarcomere
* has actin biding protein (alpha actinin)
I-band
- only thin filaments
* width decreases in contraction
H-band
- in center of A-band
- only thick filaments
- width decreases in contraction
A-band
- overlapping thick and thin filaments
* width constant in contraction
M-line
•middle of H-band
thin filament structure
f-actin forms complex with tropomyosin and troponin complex (I, T, and C)
troponin-t binds to
tropomyosin
troponin-i function
inhibits biding of myosin to actin
troponin-c binds to
Ca2+
thick filament structure
myosin that has 2 identical heavy chains and 2 pairs of light chains
heavy chains contain
biding site for actin and an ATPase domain
What happens when ATP binds to myosin head?
conformation change -> dissociation of myosin from actin filament
when ATP bound to myosin head is hydrolyzed..
thick filament hinge increases angle between head and tail, lining up head with new myosin binding site on actin filament
when is ADP released from myosin head
once it binds to actin
release of ADP causes
decrease in angle between head and tail of myosin -> thin filament slides toward center of sarcomere
rigor posistionof myosin
when no ATP is bound and it is tightly adhered to actin
depolarization of t-tubule sensed by
L-type Ca2+ channels in its membrane -> opens ryanodine sensitive Ca2+ channels in membrane of SR terminal cisternae
when calcium binds to troponin-c of actin filament
conformational changes that uncover myosin biding site allowing thick filament to bind
how is calcium returned to SR during relaxation of muscle?
ATP-dependent pump
septation of atria
- end of 4th week
- septum primum grows down from roof of common atrium leaving foramen primum
- cell death in septum primum -> foramen secundum
- septum secundum forms leaving foramen ovale
atrial septal defects can occur if
septum secundum doesn’t grow enough, or foramen secundum is too large
septation of atrioventricular canal
endocardial cushions on dorsal and ventral walls grow toward each other and fuse
atrioventricular valves formed from
endocardial cushion tissue
septation of ventricles
- muscular: myoblasts on floor of ventricle grow toward fused endocardial cusions
- membranous: forms from fused endocardial cushions and the aoritcopulmonary septum
most common congenital cardiac defect
membranous ventricular septal defect
septation of outflow tract
- beginning in 5th week
- neural crest cell migration into truncus arteriosus
- conotruncal ridges spiral and fuse
persistent truncus arteriosus
no septum forms in the outflow tract
transposition of great vessels
aorticopulmonary septum doesn’t spiral
tetralogy of fallot
- septum forms asymmetrically
- ventricular septal defect
- overriding aorta
- subpulmonary stenosis
- right ventricular hypertrophy
- caused by abnormal dev (displa1ement) of conus arteriosus from bulbus cordis
innervation of diaphragm
phrenic nerve (C3, C4, C5 ventral rami)
aortic hiatus
- level of T12
- within right and left crura of diaphragm
- aorta, thoracic duct, azygos veins
esophageal hiatus
- level of T10
- within muscular part of diaphragm
- esophagus and vagus nerves
caval opening
- level of T8
- located in central tendon of diaphragm
- IVC and sometimes right phrenic nerve
superior/inferior division of mediastinum
at sternal angle
anterior mediastinum contains
CT, fat, remnants of thymus
middle mediastinum contains
heart and roots of great vessels, and phrenic nerves
posterior mediastinum contains
descending aorta, azygous vein, thoracic ducts, esophagus, trachea, vagus nerves
pneumothorax
accumulation of air in pleural cavity -> lung collapse
recesses in pleural cavity
- costodiaphragmatic
* costomediastinal
pleural effusion
accumulation of fluid in pleural space -> fixed with thoracentesis
how to perform thoracentesis
- patient supine or sitting upright
- 1-2 intercostal spaces below effusion, but no lower than 8th intercostal space (avoid damage to lung, liver, spleen, diaphragm)
innervation of costal parietal pleura
intercostal nerves
innervation of mediastinal and diaphragmatic parietal pleura
phrenic nerves
innervation of visceral pleura
autonomic nerves
transverse pericardial sinus
- posterior to ascending aorta and pulmonary trunk
- anterior to SVC
- can be used for ligature to stop blood circulation
oblique sinus
located behind heart
coronary flow occurs during
- diastole
* R and L coronary arteries in aorta above aortic valve fill with blood when aortic valve closes
cardiac skeleton important because
electrically separates atrial from ventricular musculature
enlarged left atrium can compress
esophagus
margins of hear
- right side: 3rd costal to 6th costal cartilage
* left side: 2nd intercostal space to midclavicular 5th intercostal space
right coronary artery branches
- PDA (PIV) 85% of the time
- right marginal artery
- sa nodal
- av nodal
PDA (PIV) supplies
- right atrium
- right/left ventricle
- 1/3 of septum
right marginal arter supplies
right ventricle
left coronary artery branches
- LAD (AIV)
- left marginal
- circumflex
LAD (AIV) supplies
- right ventricle
- left ventricle
- 2/3 of septum
left marginal artery supplies
left ventricle
circumflex artery supples
- posterior surface of left ventricle
* left atrium
right main bronchus compared to left
- shorter
- wider
- more vertical
- thus more foreign bodies lodged on right side
bronchopulmonary segments
- divisions within lobes of lungs
- artery and segmental bronchus at the center
- veins at the periphery
autonomic innervation of tracheobronchial tree
- vagus nerves and T1-T4 of sympathetic trunk
- visceral afferent from vagus
- preganglionic parasymp and postganglionic symp from pulmonary plexus
intercalated discs
- in cardiac muscle
* desmosomes and gap junctions
SA node
- pacemaker
* electrical impulse from right atrium to left atrium and AV node
AV nodes
conducts impulse from atria to ventricles
bundle of His
conducts electrical impulse from AV node through cardiac skeleton and membranous IV septum
Left and Right bundle branches
group of purkinje fibers along IV septum giving rise to the purkinje fibrers distributed in ventricles
tunica intima
- simple squamous
- non-thrombogenic
- release factors that regulate smooth muscle -> regulate vascular tone
tunica media
- concentric layers of smooth muscle
- elastic fibers
- type III collagen
- proteoglycans
- primarily regulates vascular tone, vessel diameter, and BP
tunica adventitia
- CT layer with fibroblasts, type I collagen, elastic fibers
- vasa vasorum
- sympathetic nerve fibers
capillaries
- site of fluid, gas, and small molecule exchange between blood and tissues
- single layer of endothelial cells and basement membrane
- pericytes = sphincter can be associated with outer wall
continuous capillaries
- found in muscle, nerve, CT
- tight junctions resist leakage
- pinocytosis
fenestrated capillaries
- found in GI and endocrine
* permanent channels along endothelial cells
sinusoidal capillaries
- found in bone marrow, liver, spleen
* large discontinuities between endothelial cells
angiogenesis
- formation of new capillaries from existing
* stimulation of endothelial cells by VEGF (vascular endothelial growth factor)
mucosa of conducting respiratory system
- ciliated pseudostratified columnar epithelium with goblet cells
- as you approach respiratory portion, goblet cells decrease and changes to simple columnar and cuboidal
submucosa of conducting respiratory system
- smooth muscle cells that increase in # as diameter of tube decreases
- hyaline cartilage that decreases as tube diameter decreases
- seromucous glands
bronchioles don’t have
goblet cells, seromucous glands, or cartilage
epithelium=cuboidal
type I alveolar cells / pneumocytes
- squamous, 97% alveolar surface
- desmosomes and tight junctions
- form gas permeable membrane
type II alveolar cells / pneumocytes
- cuboidal
* produce surfactant
alveolar macrophage/ dust cell
- derived from monocytes
* phagocytose carbon and dust from alveolar lumen
blood-air barrier
- surface and cytoplasm of type I alveolar cells
- fused basal laminae of alveolar and capillary endothelial cells
- cytoplasm of endothelial cells
anterior rectus sheath formed by
- aponeurosis of external oblique
* part of aponeurosis of internal oblique
posterior rectus sheath formed by
- part of aponeurosis from internal oblique
* aponeurosis of transverse abdominus
arcuate line
where the posterior rectus sheath ends and all that rectus abdominus rests on is transversalis fascia
direct inguinal hernia
weakness in musculature of abdominal wall through hesselbach’s triangle
indirect inguinal hernia
congenital defect in inguinal canal
MDs don’t LIe
•direct hernia medial to inferior epigastric arteries
•indirect lateral
both above inguinal ligament
femoral hernia
below inguinal ligament
peritoneal epithelium
simple squamous (serous)
pain from parietal peritoneum
- shares sensory innervation with abdominal wall (T7-L1)
* sharp and localized
pain from visceral peritoneum
•diffuse and dull referred pain
pain from foregut organs refers to
epigastric
pain from midgut organs refers to
umbilical
pain from hindgut organs refers to
pubic (hypogastric)
epiploic foramen (of winslow)
entrance to lesser sac from greater sac
foregut includes
esophagus, stomach, 1st half of duodenum and associated organs
midgut includes
second half of duodenum, jejunum, ileum, ascending colon, and first 2/3 of transverse colon
hindgut includes
last 1/3 of transverse colon, descending colon, sigmoid colon, and rectum
anastamosis at foregut-midgut junction
superior pancreaticoduodenal (celiac trunk) inferior pancreaticoduodenal (SMA)
anastamosis at midgut-hingut junction
middle colic (SMA) left colic (IMA)
anastamosis at rectum
superior rectal (IMA) Middle and inferior rectal arteries (internal iliac)
hepatoduodenal ligament contains
•proper hepatic artery
•portal vein
•common bile duct
(anterior to epiploic foramen)
rotation of stomach in embroylogic dev
90 degrees clockwise on longitudinal axis so left side faces anteriorly
spleen develops from
mesoderm in dorsal mesentery of stomach
midgut rotation
- 270 degrees around axis of SMA during herniation and upon return
- jejunum returns first to left side
- ileum returns to right side
- cecum returns last: RUQ then RLQ
hypertrophic pyloric stenosis
- projectile nonbilious vomiting
- sx usually begin 3-5 weeks after birth
- etiology unclear
annular pancreas
- vomiting (usually nonbilious) and abd distention
- sx begin in neonatal period with feeding
- ventral pancreatic bud has 2 lobs that form a ring around 2nd part of duodenum
meckel’s diverticulum
- persistence of yolk stalk (vitelline duct)
- ectopic gastric mucosa may be present
- rule of 2s
volvulus
- vomiting, absence of stool, abd distention
- can obstruct SMA
- malrotation of midgut
duodenal atresia
- failed recanalization
- bilious vomit and abd distention
- double bubble sign
- associated with polyhydramnios
intussusception
- segment of intestine invaginates or telescopes into adjacent
- intermittent abd pain, vomiting, bloating, bloody stool
aganglionic megacolon (hirschsprung’s disease)
- lack of ganglia in colon
- defect in RET gene (involved in neural crest cell migration)
- fecal retention and abdominal distention
esophagus histology
- thick nonkeratinized stratified squamous
- submucosal glands
- thoracic esophagus has adventitia, abdominal esophagus has serosa
stomach histology
- simple columnar epithlial lining consisting entirely of mucous-secreting cells
- gastric glands open into pits in mucosa
- 3 layers in muscularis: inner oblique, middle circular, outer longitudinal
mucous cells in gastric glands
secrete mucous rich in bicarbonate
parietal cells in gastric glands
- produce HCl (pepsinogen -> pepsin)
* produce intrinsic factor (absorption of vit B12)
chief cells in gastric glands
•secrete pepsinogen
enteroendocrine cells in gastric glands
- secrete serotonin (effect gut motility)
* secrete gastrin (effect HCl secretion)
pepsin
proteolytic enzyme capable of digesting most proteins
small intestine histology
- luminal surface has plica circulares with villi
- mucosa simple columnar with tight junctions, goblet cells, paneth cells, enteroendocrine cells
- crypts of lieberkuhn
enterocytes of small intestine
absorptive and have microvilli (brush border)
paneth cells
lysozyme secreting (antibacterial)
cholecystokinin
- secreted by enteroendocrine cells in small intestine
* stim secretion from pancreatic acinar cells and release bile from gallbladder
secretin
- secreted by enteroendocrine cells in small intestine
- released in response to gastric acid
- stim release of HCO3 from pancreas and liver
gastric inhibitory peptide
- secreted by enteroendocrine cells in small intestine
* stim insulin secretion from pancreatic islets
glucagon like peptide
- secreted by enteroendocrine cells in small intestine
* stim insulin secretion and inhibits glucagon secretion
brunners glands
- found only in mucosa of DUODENUM
* secrete alkaline mucous
peyer’s patches
- found in lamina propria of ILEUM
* concentrated lymphocytes (AKA GALT)
histology of large intestine
- simple columnar with goblet cells
- crypts without villi
- teniae coli (longitudinal bands of longitudinal muscle
- epiploic appendages on the serosa
merocrine secretion of pancreatic proenzymes regulated by
- secretin and cholecystokinin from small intestine
* stimulation by vagus nerve
alpha cells of pancreatic islet
produce glucagon -> increase blood glucose, gluconeogenesis, and glycogenolysis
beta cells of pancreatic islet
produce insulin -> decrease blood glucose, stim storage of glucose as glycogen
delta cells of pancreatic islet
produce somatostatin -> inhibit secretion of glucagon and insulin
blood flow in hepatic lobule
from periphery to center (zone I to zone III)
hepatocytes near zone I
- can rely on aerobic metabolism
* more active in protein synth
hepatocytes near zone III
- get lower [O2] and nutrients
* more involved in detoxification and glycogen metabolism
bile flow in liver
opposite to blood flow (zone III to zone I)
kupffer cells
- phagocytic cells found in sinusoids of liver
* remove aged RBCs, bacteria and other debris
Ito cell
- in space of disse
* stores vitamin A and other fat-soluble vits
broad ligament
- mesometrium
- mesovarium
- mesosalpinx
suspensory ligament of ovary
contains ovarian vessels
ovarian ligament
attaches it to uterus
round ligament of uterus
- continuous with ovarian ligament
* enters deep inguinal ring
stress incontinence can be cause by damage to
- pubovesicle ligaments
- transverse cervical ligaments (cardinal)
- uterosacral ligaments
bladder prolapse involves
pubovesical ligaments
uterine prolapse involves
transverse cervical (cardinal) ligaments
layers of spermatic cord
- external spermatic fascia (ext oblique aponeurosis)
- cremasteric fascia/muscle (internal oblique)
- internal spermatic fascia (transversalis fascia)
parasympathetic innervation of pelvic organs
- preganglionic: pelvic splanchnic (S2-S4)
* ganglia: located in wall of organ
sympathetic innervation of pelvic organs
- preganglionic: lesser and least splanchnic (T10-T12) and lumbar splanchnic (L1-L2)
- ganglia: pelvic ganglia
- postganglionic: hypogastric plexus (ovarian plexus to ovary and testicular plexus to testis/epididymis)
visceral afferents inferior to pelvic pain line
- structures that don’t contact peritoneum + sigmoid colon and rectum
- follow parasympathetic fibers
visceral afferents superior to pelvic pain line
- structures in contact with peritoneum - sigmoid colon and rectum)
- follow sympathetics
mesonephric duct becomes
epididymis, vas deferens, and seminal vesicles
paramesonephric duct becomes
uterus, uterine tubes, and upper vagina
Wnt4 ->
maintain oocytes
SRY gene
produce testis determining factor (TDF)
MIS or AMH
•same thing anti-mullerian hormone/mullerian inhibiting substance
•produced by sertoli cells in respons to
TDF
in embryogenesis leydig cells produce
testosterone -> differentiation mesonephric duct
dihydrotestosterone
- 5-alpha reductase converts testosterone into this
* cause dev of penis, scrotum, prostate
prostate and bulbourethral gland bud off
urethra
lower vagina forms from
sinovaginal bulbs (proliferaltion of endodermal tissue on posterior wall of urogenital sinus)
leydig cells
- found in space between seminiferous tubules
* produces testosterone in response to LH
sertoli cells
- columnar epithelium found in seminiferous tubule
- secrete ABP in response to FSH
- also phagocytose residual germ cell cytoplasm and regulate release of mature spermatozoa
which spermatogenic cells are diploid
spermatogonia and primary spermatocytes
spermatogenesis sequence
spermatogonia -> primary spermatocyte -> meiosis I -> secondary spermatocyte -> meiosis II -> spermatid -> spermiogenesis -> spermatozoa
histology of epididymis
- pseudostratified columnar with long branched stereocilia
- principle cells with stereocilia
- basal cells that are precursors for principle cells
histology of vas deferens
- pseudostratified columnar with stereocilia
* thick muscular layer
zones of prostate gland
- transition zone around urethra
- central zone around ejaculatory ducts
- peripheral zone
corpora amylacea
concretions often found in prostate gland that can be site of calcium deposition
benign prostate hyperplasia most often involves
cells and stroma of central and transitional zones
prostate cancer most often involves
peripheral zone
ovarian surface epithelium
(OSE)
•simple squamous-to-low-cuboidal
•important stem cell that repairs damage caused by ovulation
ovarian cycle
- follicular phase
- ovulatory phase
- luteal phase
steps of folliculogenesis
primordial follicle -> primary (unilayered) follicle -> secondary (multilayered) follicle ->antral follicle -> graffian (preovulatory) follicle
corpus luteum
- granulosa lutein cells (from granulosa) -> progesterone/estrogen in response to FSH and LH
- theca lutein cells (from theca interna) -> androstenedion and progesterone in response to LH
estradiol
made from androstenedione (from theca lutein) by aromatase within granulosa lutein
corpus albicans
luteolysis of corpus luteum occurs if hCG does not stimulate it to continue producing hormones
what stimulates thickening of endometrium during proliferative phase?
estrogen produced by maturing ovarian follicles
secretory phase controlled by
progesterone and estrogen produced by corpus luteum
what initiates ischemic phase
regression of corpus luteum
foramina of anterior cranial fossa
cribriform plate
foramina of middle cranial fossa
C/O canals, ROS foramen, and 1 fissure •carotid canal •optic canal •foramen rotundum •foramen ovale •foramen spinosum •superior orbital fissure
foramina of posterior cranial fossa
HIJ + magnum •hypoglossal canal •internal acoustic meatus •jugular foramen •forament magnum
what runs through superior orbital fissure
CN III, IV, V1, and VI
what runs through foramen rotundum
maxillary nerve
what runs through foramen ovale
mandibular nerve
what runs through carotid canal
internal carotid artery and internal carotid nervous plexus (sympathetic)
what runs through internal acoustic meatus
CN VII and VIII
what runs through jugular foramen
CN IX, X, and XI
and sigmoid sinus
what runs through foramen magnum
- vertebral arteries
- spinal contribution to CN XI
- anterior and posterior spinal arteries
epidural hematoma
- middle meningeal artery
- usually fx of temporal bone
- brief LOC -> lucid interval -> HA, AMS, weakness
- convex hyperdensity on CT (lemon)
subdural hematoma
- bridging veins
- elderly and alcoholics susceptible
- HA and AMS w/o other clinical findings
- concave hyperdensity of CT (banana)
subarachnoid hemorrhage
- stroke with bleeding into subarachnoid space
- sudden onset severe headache, n/v, neck/back pain, dizzy, sz
- LP would show blood
innervation of extraocular muscles
LR6, SO4, ATR3
test superior rectus
look lateral and up
test inferior rectus
look lateral and down
test inferior oblique
look medial and up
test superior oblique
look medial and down
nasal septum formed by
vomer and perpendicular plate of ethmoid bone
sphenoid sinus drains into
spehnoethmoidal recess
ethmoid sinus drains into
superior and middle meatuses
frontal sinus drains into
middle meatus
maxillary sinus drains into
middle meatus
nasolacrimal duct drains into
inferior meatus
epistaxis often involves
septal branch of superior labial artery from facial artery
vestibule of larynx
- supraglotic
* above vestibular folds
ventricle of larynx
- glottic
* between vestibular and vocal folds
infraglottic region of larynx
- subglottic
* below vocal folds
only laryngeal muscles that abduct (open) vocal folds
posterior cricoarytenoids
position of rima glottidis in quiet respiration
open/ abducted vocal folds
position of rima glottidis in swallowing
•closed/ adducted vocal folds
+epiglottis swings down to close laryngeal vesibule
position of rima glottidis in phonation (speech)
closed/ abducted vocal folds
superior laryngeal branch of vagus nerve
- motor to cricothyroid
* sensory to mucosa above vocal folds
recurrent laryngeal branch of vagus nerve
- motor to all muscles except cricothyroid
* sensory to mucosa below vocal folds
only cranial nerves arising from cerebrum
CN I and II (all others from brainstem)
cranial nerves that transmit parasympathetic information
CN III, VII, IX, and X
branches of opthalmic nerve (V1)
- frontal nerve gives a branch to lacrimal gland and then exits supraorbital foramen and becomes supraorbital nerve
- smaller branches give sensation to cornea and conjunctiva
supraorbital nerve sensory to
- branch of V1
* sensation to scalp, forehead and nose
branches of maxillary nerve (V2)
- infraorbital nerve
* superior alveolar nerve
superior alveolar nerve sensory to
- branch of V2
* sensation to upper teeth/palate, some sinuses, and nasal mucosa
infraorbital nerve sensory to
- branch of V2
* sensation to cheeks, lower eyelids, and upper lip
branches of mandibular nerve (V3)
sensory:
•buccal - inside mouth and cheek
•ariculotemportal - skin around external ear
•lingual - anterior 2/3 of tongue
•inferior alveolar - lower teeth -> mental nerve - lower lip/face
motor:
•supply temporalis, masseter, medial/lateral pterygoids
innervation of parotid gland
- Parasympathetic
- preganglionic - lesser petrosal of glossopharyngeal
- otic ganglion
- postganglionic - ariculotemporal branch of V3
travel of facial nerve in skull
internal acoustic meatus -> petrous part of temporal bone -> out stylomastoid foramen
innervation and function of stapedius muscle
- branch of facial nerve
* attaches to stapes and dampens sound received from TM
temporal branches of facial nerve innervate
frontalis, orbicularis oculi, and corrugator supercili
zygomatic branches of facial nerve innervate
orbicularis oculi
buccal branches of facial nerve innervate
orbicularis oris, buccinator, zygomaticus
marginal mandibular branches of facial nerve innervate
mentalis
cervical branch of facial nerve innervates
platysma
chorda tympani nerve
- branch of facial nerve
- taste from anterior 2/3 of tongue
- also parasympathetic to sublingual and submandibular salivary glands
glossopharyngeal nerve
- CN IX
- sensory to posterior 1/3 tongue, palate, and oropharynx
- afferent of gag reflex
- motor to pharynx
- taste from posterior 1/3 of tongue
vagus nerve
- CN X
- sensory external ear, larynx, esophagus
- motor muscles of pharynx, larynx, palate, and esophagus
- efferent of gag reflex
double layer of epithelium on ciliary body
- inner: pigmented
* outer: secrete aqueous humor
flow of aqueous humor
posterior chamber -> through pupil -> anterior chamber -> drains at trabecular meshwork of limbus
acute/ closed angle glaucoma
•flow aqueous humor obstructed by iris tissue
chronic/ open angle glaucoma
drainage of aqeuous humor from trabecular meshwork is impaired
when ciliary muscle relaxes
- tension on zonular fibers -> flat lens
* distance vision
when ciliary muscle contacts
- laxity to zonular fibers 0 -> round lens
* close vision
oxytocin
- made by paraventricular nuclei of hypothalamus
- stored posterior pituitary
- uterine contraction and lactation
ADH
- =antidurietic hormone = vasopressin
- made by supraoptic nuclei of hypothalamus
- stored posterior pituitary
- decrease urine production/constric arterioles -> increase BP
growth hormone
- anterior pituitary acidophils
* bone and soft tissue growth
prolactin
- anterior pituitary acidophils
* initiation/maintenance of lactation
TSH
- anterior pituitary basophils
* stimulate thyroid to make T3 and T4
FSH
- anterior pituitary basophils
* stimulate follicle development
LH
- anterior pituitary basophils
* stimulate testosterone production -> spermatogenesis
ACTH
- =adrenocorticotrophic hormone
- anterior pituitary basophils
- cause cortisol and androgen release -> regulation of metabolism and immune responses, secondary sex characteristic
parafollicular cells
- =c cells
- found in interstitium around thyroid follicles
- produce calcitonin -> lowers blood calcium by acting on osteoclasts (decrease bone turnover) and kidney/gut (increase calcium excretion)
thyroglobulin synthesis (exocrine phase)
- TSH stimulates follicular cell
- iodide uptake via ATP dependent pump
- diffusion of iodide through cell
- synthesis of thyroglobulin and exocytosis into colloid
- oxidation of iodide by thyroid peroxidase
- transfer of iodine to tyrosyl residues of thyroglobulin
- storage of iodothyroglobulin in colloid
thyroid hormone synthesis and release (endocrine phase)
- TSH stimulates follicular cell
- colloid droplet containing iodothyroglobulin endocytosis
- fusion of droplet with lysosome and degradation to T3 and T4
- release of T3 and T4 into bloodstream and interaction with binding proteins
Thyroid hormon
- =T3 and T4
- increase basal metabolic rate in adults
- influence growth and neurological development in fetus
foregut sympathetic innervation
- T5-T9
- pre: greater splanchnic
- post: celiac plexus
foregut parasympathetic innervation
vagus
midgut sympathetic innervation
- T5-T9 pre: greater splanchnic
- T10-T11: lesser splanchnic
- post: superior mesenteric plexus
midgut parasympathetic innervation
vagus
hindgut sympathetic innervation
- L1-L2
- pre: lumbar -> post: inferior mesenteric plexus
- pre: sacral splanchnic -> post: hypogastric plexus via pelvic ganglia
hindgut parasympathetic innervation
pelvic splanchnic nerves (S2-S4)
valgus stress ->
medial collateral ligament
varus stress ->
lateral collateral ligament
lachman’s test
•for ACL
SAD PUCKER
Retroperitoneal structures: S suprarenal glands A aorta/ivc D duodenum (2-4 parts) P pancreas (except tail) U ureters C colon (ascending and descending) K kidneys E esophagus (thoracic portion) R rectum