Anatomy Flashcards
Blood supply to SA/AV nodes
Right coronary artery (RCA infarct) = nodal dysfunction
Dominance in coronary circulation
R-dominant: RCA gives rise to PDA (70%)
L-dominant: LCX gives rise to PDA (20%)
Co-dominant: arises from both (10%)
LA can impinge on what 2 structures?
Enlargement of the left atrium can lead to…
- dysphagia: compression of esophagus
- hoarseness: compression of L recurrent laryngeal
Adrenal cortex anatomy (also, give stimulation and product of each region)
From the outside in: GFR
G: glomerulosa = stim. by renin-angiotensin system, secretes aldosterone
F: fasciculata = stim. by ACTH/CRH, secretes cortisol
R: reticularis = stim. by ACTH/CRH, secretes DHEA (androgen precursor), DHEA-S (marker for adrenal dysfunction), androstenedione (testosterone precursor)
Increased 17-OHP = congenital adrenal hyperplasia
Adrenal medulla derivative, cell type, innervation
neural crest derivative
- chromaffin cells (neural crest), regulated by preganglionic sympathetics
- secretes catecholamines (site of pheochromocytoma)
- neuroblastoma comes from the adrenal medulla
Pituitary gland secretory products and embryonic derivative
Anterior: FLAT PiG (FSH, LG, ACTH, TSH, prolactin, GH), derived from oral ectoderm, alpha subunit of hormones is common
Posterior: vasopression and oxytocin (technically made in hypothalamus, then transported by neurophysins), derived from neuroectoderm
Pancreatic islet cells organization
Alpha cells: found on periphery of islet (secrete glucagon)
Beta: found in center of islet (secrete insulin)
Delta: found throughout islet (secrete somatostatin)
Retroperitoneal structures
SAD PUCKER: Suprarenal (adrenal) glands, Aorta/IVC, Duodenum, Ureters, Colon (asc/desc), Kidneys, Esophagus, Rectum (superior part)
GI ligaments to know
Falciform Hepatoduodenal Gastrohepatic Gastrocolic Gastrosplenic Splenorenal
Falciform (liver to anterior wall): ligamentum teres hepatis (ventral mesentery)
Hepatoduodenal: portal triad, part of lesser omentum, compression = Pringle maneuver
Gastrohepatic: to lesser curvature of stomach, contains gastric arteries (separates lesser and greater sacs)
Gastrocolic: greater curvature to colon, contains gastroepiploics, part of greater omentum
Gastrosplenic: short gastrics, left gastroepiploics, greater omentum
Splenorenal: splenic artery and vein, tail of pancreas
Digestive tract facts
- layers of wall/mucosa
- wave speeds
4 layers in wall: mucosa, submucosa, muscularis, serosa
mucosa = epithelium, lamina propria, muscularis mucosa (site of myenteric plexus)
duodenum: 12/min > ileum: 8-9/min > stomach: 3 waves/min
GI tract histology notable features (esophagus, stomach, duodenum, ileum, colon)
Esophagus: non-keratinized stratified squamous
Stomach: gastric glands
Duodenum: villi/microvilli, Brunner glands (HCO3),
Ileum: Peyer’s patches,
Colon: no villi! abundant goblet cells
Abdominal aorta branch vertebral heights
Celiac T12 SMA L1 Left renal L1 IMA L3 Bifurcation of aorta L4
Portosystemic anastomoses
Esophageal: L gastric vein –> esophageal vein (to azygos to SVC)
Umbilical: paraumbilical veins —> small superficial epigastrics
Rectal: superior rectal –> middle/inferior rectal
Tx: TIPS: portal vein to hepatic vein (bypasses liver entirely)
Pectinate line (endoderm meets ectoderm)
Give innervation, blood supply and drainage
Above: internal hemorrhoids (visceral innervation), adenocarcinoma
supplied by IMA, drained to portal vein
Below: external hemorrhoids (somatic = painful!), SCC
supplied by internal pudendal, drains to IVC
anal fissures: posterior due to poor perfusion
Liver anatomy (lobule structure, Zones, describe insults)
Apical = bile secretion, basolateral = sinusoids
Blood flow = portal vein (apical) to hepatic vein (basolateral)
Zone 1 (apical, periportal): affected first by viral hepatitis, ingested toxins Zone 2 (intermediate): location of hepatic infection by yellow fever Zone 3 (basolateral, centrilobular): affected first by ischemia, location of alcoholic hepatitis/toxic injury and p450 system
Femoral triangle (borders and contents)
Superior = inguinal ligament, lateral = sartorius, medial = adductor longus
NAVEL (lateral to medial): Nerve, Artery, Vein, Lymph
femoral sheath: includes artery, vein, lymph (not the nerve!)
Inguinal canal layers
Peritoneum, transversalis, transversus abdominus, internal oblique, external oblique, inguinal ligament, superficial inguinal ring
Hernias (diaphragmatic, indirect, direct, femoral)
Diaphragmatic: left-sided, hiatal is most common (sliding = upward displacement of GEJ, parasophageal = protrusion of fundus)
Indirect inguinal: processus vaginalis into scrotum, lateral to inferior epigastric (more common in infants!)
Direct inguinal: peritoneum bulges through Hesselbach triangle (older men)
Femoral: below inguinal triangle, lateral to pubic tubercle (more common in females, bowel incarceration)
Erythrocyte facts (life span, membrane protein)
life span: 120 days
membrane contains Cl-/HCO3- antiporter (export of HCO3 to allow for CO2 carrying)
Thrombocyte facts (life span, granules, receptors)
life span 8-10 days
Dense granules: ADP, Ca2+
Alpha granules: vWF, fibrinogen
vWF receptor: GpIb
fibrinogen receptor: GpIIb, IIIa
Neutrophil facts (granules contents, chemotactic factors)
Granules = ALP, collagenase, lysosome, lactoferrin (help with phagocytosis)
chemotactic factors: C5a, IL-8, kallikrein, CTB4
Macrophage facts (activation)
activated by IFN-y
septic shock mediator: responds to Lipid A, LPS, CD14
Eosinophil (give 5 causes of eosinophilia)
5 causes of increased eos:
neoplasia, asthma, allergies, chronic adrenal insufficiency, parasite
Basophil granules
Heparin and histamine
Mediate allergic reactions
Mast cell facts
local allergic reaction, bind Fc of IgE in allergic reactions
Type I hypersensitivity reactions
- cromolyn sodium = decreased histamine release (used to prevent asthma attacks)
Lymphocyte facts (receptors, site of maturation)
B cell
T cell
Plasma cell
B cell (CD19/20, surface, 21, EBV receptor) - mature in bone marrow, stored in peripheral lymphoid tissue T cell (CD3, then CD4/8) - matures in thymus (CD4+ = HIV target) Plasma cell - clock-face chromatin, abundant RER, well-developed Golgi (multiple myeloma is a plasma cell cancer!)
Drawer test
ACL/PCL injury (abnormal anterior drawer = ACL injury)
ACL inserts on the anterior aspect of the tibia from the lateral femoral condyle
PCL inserts on posterior aspect of the tibia from the medial femoral condyle
McMurray test
click on external rotation = medial meniscus tear
click on internal rotation = lateral meniscus tear
Unhappy triad of knee injuries
ACL tear
MCL tear
medial/lateral meniscus
Baker cyst
popliteal fluid collection, related to chronic joint disease (knee arthritis or meniscal tear)
Most common rotator cuff injury
Supraspinatus
Test with empty can test
Pitching injury
Infraspinatus
Epicondylitis
Medial = golfer's (repeated flexion) Lateral = tennis (repeated extension)
Wrist bone syndromes (also, give bones of the wrist)
So Long To (Triq) Pinky, Here Comes The (Trapezoid) Thumb (Trapezium)
Scaphoid: avascular necrosis due to retrograde blood supply
Lunate: acute carpal tunnel syndrome
Carpal tunnel associations
Pregnancy, rheumatoid arthritis, hypothyroidism
Guyon canal syndrome (give association)
Compression of ulnar nerve at the wrist
Often seen in cyclists
Humerus surgical neck fracture
Axillary nerve injury
Decreased abduction of arm at shoulder
Decreased sensation over the deltoid
Upper trunk of brachial plexus compression
Musculocutaneous nerve injury
Decreased forearm flexion at elbow, supination
Decreased sensation over lateral forearm
Midshaft humerus fracture
Radial nerve injury (lies in spiral groove)
Leads to wrist drop (loss of extensors), decreased grip strength
Loss of sensation over posterior arm and dorsal hand
Supracondylar fracture of humerus
Median nerve injury
Loss of wrist flexion, 2nd/3rd finger flexion (ape hand, Pope’s blessing)
Loss of sensation over thenar eminence
Tinel sign - tingling on percussion
Fracture of medial epicondyle of humerus
Ulnar nerve injury
Loss of wrist flexion, flexion of ulnar fingers, interossei
Loss of sensation over ulnar hand
Superficial laceration of palm
recurrent branch of median nerve
Loss of thenar muscle group: opposition, abduction, flexion of thumb
No loss of sensation
Tear of upper trunk (lateral pull during dystocia)
Erb’s Palsy (tear of C5-C6 nerve roots)
Waiter’s tip: arm adducted (deltoid), internally rotated (infraspinatus), extended (biceps)
Tear of lower trunk (upward pull during dystocia)
Klumpke’s palsy (tear of C8-T1 nerve roots)
Total claw hand: loss of lumbricals, interossei, thenar and hypothenar eminence
Compression of lower trunk and subclavian vessels (extra cervical rib, Pancoast tumor)
Thoracic outlet syndrome
Same muscle deficits as Klumpke’s, but also ischemia, pain and edema due to vascular compression
Winged scapula
lesion of long thoracic nerve (axillary node resection)
Loss of serratus anterior
Pope’s blessing (first two extended, last two flexed)
If present during extension/rest: distal ulnar lesion (ulnar clawing)
If present during flexion: proximal median lesion
Okay sign (first two flexed, last two extended)
If present during extension/rest: distal median lesion (median clawing)
If present during flexion: proximal ulnar lesion
Thenar eminence muscles
Opponens pollicus, Abducens pollicus longus, Flexor pollicus longus
Innervated by median nerve
Hypothenar eminence muscles
Opponens digiti minimu, Abductor digiti minimi, Flexor digiti minimi
Innervated by ulnar nerve
Interossei function and innervation
Dorsal = abduction Palmar = adduction
DAB, PAD
Innervated by ulnar nerve
Pelvic surgery nerve injury (motor and sensory deficits)
Obturator (L2-L4)
decreased thigh sensation
decreased adduction
Pelvic fracture nerve injury (motor and sensory deficits)
Femoral (L2-L4)
decreased thigh flexion, leg extension
Trauma/compression of lateral leg
Fibular neck fracture
Common peroneal nerve injury (L4-S2)
Foot drop, steppage gait
Loss of eversion and dorsiflexion
PED = peroneal everts and dorsiflexes
Knee trauma
Baker cyst
Tarsal tunnel syndrome
Tibial nerve injury (L4-S3)
Loss of sole of feet
Inability to curl toes
TIP: tibial inverts and plantarflexes
IM injection nerve injury
Superior gluteal (L4-S1) trendelenburg gait Lesion is on the side on which the patient stands (opposite to the hip that drops)
Posterior hip dislocation
Inferior gluteal (L5-S2)
difficulty climbing stairs, rising from seated position
Loss of hip extension
Nerve block during birth
Pudendal nerve
Innervates perineum
Found near ischial spine
Lumbosacral radiculopathy
Nerve is inferior to the disc (L4 nerve is damaged in L3-L4 herniation)
L3-L4: decreased patellar reflex
L4-L5: decreased dorsiflexion, no heel-walking
L5-S1: decreased plantarflexion, difficulty in toe-walking, decreased Achilles reflex
Proteins involved in muscle conduction to contraction
Nerve: presynaptic Ca channels, NT release
Muscle cell: DHP receptor (voltage-gated), ryanodine (sarcoplasmic reticulum), troponin C (moves tropomysoin out of the myosin-binding groove)
Myosin cycle in muscle contraction
After opening of binding groove by troponin C…
- myosin binds to actin filament
- myosin releases ADP and Pi in the power stroke
- new ATP binds and causes detachment of myosin from actin
- hydrolysis of ATP cocks myosin into high-energy position for next cycle
Skeletal muscle microscopic structure
Z-line - borders of the sarcomere (center of light actin chain)
M-line - middle of the sarcomere (center of heavy myosin chain)
A-band - Myosin heavy chain, Always same length!
H-band - distance between light chains (myosin only)
I-band - distance between heavy chains (actin only)
During contraction, H-band and I-band contract, and Z-lines and M-lines move closer together
Type 1 vs. Type 2 muscle fibers
Type 1: slow twitch, reddish color due to increased myoglobin concentration and increased mitochondria for sustained contraction (1 slow red ox)
Type 2: fast twitch, white fibers from decreased mitochondria, increased anaerobic glycolysis (weight-training = increased fast-twitch muscle)
Smooth muscle contraction
mediated by calcium, regulated by calmodulin
L-type voltage gated channel allows Ca influx, increases myosin-light-chain kinase activity (MLCK), increased myosin-P + actin, contraction via cross-bridging
Smooth muscle relaxation
mediated by NO
Increases intracellular guanylate cyclase, increased cGMP, increased myosin-light-chain phosphorylase (MLCP)
Endochondral bone formation
Axial/appendicular skeleton
Chondrocytes make cartilaginous model, which is later replaced by osteoclasts/blasts to remodel into lamellar bone
Woven bone is formed later after fractures and in Paget disease
Membranous ossification
Bones of calvarium/skull, facial bones
Woven bone formed without cartilage first, later remodeled to lamellar bone
Effect of PTH on bone
low levels = anabolic effects (building bone)
high levels = catabolic effects (osteitis fibrosa cystica)
Estrogen effects on bone
Induces apoptosis in bone-resorbing osteoclasts
Decreased estrogen leads to excess remodeling/resorption –> osteoporosis
Ureter course
The ureters pass under the uterine artery (or under the vas deferens) prior to entering the bladder
Venous drainage of the gonads
Left gonadal veins drain into the L renal vein at a 90 degree angle, thus have less laminar flow, therefore increased risk of varicocele on the left (dilation of pampiniform plexus)
Right gonadal vein drains directly into the IVC
Lymphatic drainage of the gonads
ovaries/testes –> paraaortic
Distal vagina/scrotum –> superficial inguinal
Proximal vagina –> obturator/hypogastric nodes
Infundibulopelvic ligament
Suspensory ligament
ovaries –> lateral pelvic wall
contains ovarian vessels!
When operating, there is risk of ligating the ureter
Cardinal ligament
cervix –> pelvic side wall
contains uterine vessels
Round ligament
Uterine fundus –> labia majora
contains artery of Sampson
(remnant of gubernaculum)
Broad ligament
uterus/ovaries –> side pelvic wall
Ovarian ligament
ovary –> uterus
remnant of gubernaculum
Histology of female repro tract
stratified squamous, simple columnar, simple cuboidal
Stratified squamous: vagina, ectocervix
Simple columnar: endocervix, uterus (glands are tubular in follicular phase, coiled in luteal phase), fallopian tube (ciliated)
Simple cuboidal: outer surface of ovary
SEVEN-UP
Seminiferous tubules Epididymis Vas deferens Ejaculatory duct (nothing) Urethra Penis
Urethra segments
Posterior: membranous (pelvis fractures), bulbar (blunt force)
Anterior: penile (perineal straddle - leads to urine Buck’s fascia)
Erection mechanisms (nerves: pelvic, hypogastric, pudendal)
NO –> increased cGMP –> smooth muscle relaxation –> vasodilation
Norepinephrine –> increased [Ca]i –> smooth muscle contraction –> vasconstriction
Emission: sympathetic
Ejaculation: visceral/somatic
Sertoli cell functions
- located in tubule wall
- secrete inhibin B (responds to FSH) = decreased FSH
- forms blood-sperm barrier (tight junctions)
- temperature sensitive (increased temp = decreased inhibin, decreased sperm)
Leydig cell functions
increased LH = increased testosterone
unaffected by temperature
Conducting zone of lungs
no gas exchange!
anatomic dead space
Cartilage/goblet cells - until the end of bronchi
Pseudostratified ciliated columnar cells - until end of terminal bronchioles (therefore, mucociliary clearance happens until end of terminal bronchioles)
Respiratory zone
lung parenchyma: respiratory bronchioles, alveolar ducts, alveoli
Mostly cuboidal until alveoli, then simple squamous
Pneumocytes (Type I, Type II, Clara)
Type I: line alveoli, squamous, gas diffusion
Type II: pulmonary surfactant, cuboidal/clustered
- precursors to Type I and other Type II
- proliferate during lung damage
Clara cells: non-ciliated, secretory granules
- secrete part of surfactant, degrade toxins
Bifurcations to know: (all at 4!)
Common carotid: C4
Trachea: T4
Abdominal aorta: L4
