Flashcards in Musculoskeletal Deck (102):
What is the anterior drawer sign? What does it mean? What is posterior drawer sign? What does is it mean? What is abnormal passive abduction? What does it mean? What is abnormal passive adduction ?What does it mean? What is the mcmurray test? What are some signs and what do they mean?
Pt supine, knee at 90 degree, incr. anterior gliding of tibia
Pt suping, knee at 90 degr., incr. posterior gliding of tibia
Pt. supine and knee either extended or at 30 degr. angle, lateral (valgus) fore leads to medial space widening of tibia.
Same as above, medial (varus) force leads to lateral space widening of tibia
With pt. supine, knee internally and extenally rotated during range of motion:
Pain, popping on external rotation=Medial meniscal tear
Pain, popping on internal rotation=lateral " "
What is the unhappy triad? What causes it? Presentation?
What is prepatellar bursitis? Cause? What is a baker cyst? Association?
Contact sports; lasteral force applied to planted leg.
Classically, damage to ACL, MCL, and medial lemniscus (thought its usually the lateral one)
Acute knee pain and signs of joint injury/instability
Housemaids knee. Inflammation/liquid above patella.
Repeated trauma or pressure from extensive kneeling
Popliteal fluid collection
Chronic joint disease
What are the muscles that form the rotator cuff? Where are they located in relation to each other? What is the innervation of each? What is the function of each? What spinal levels primarily innervate them? Which is most commonly injured? Which is injured in pitching?
superior to humerus
Abducts arm initially (before action of deltoid)
Posterior superior to humerus
Laterally rotates arm
Posterioinferior to humerus
Laterally rotates arm and adducts arm
Anterior to humerus
Upper and lower subscap nerve
Adducts and medially rotates arm
What is medial epicondylitis? Another name? Cause? Presentation? Same Qs for lateral epicondylitis?
Repetitive flexion (forehand shots) or idiopathic
pain near medial epicondyle
Repetitive extension (backhand shots) or idiopathic
Pain near lateral epicondyle
What are the wrist carpal bones? Which is palpated in the anatomical snuff box? Which is most commonly fracture? Complications of fracture/mechanism? What can cause carpal tunnel syndrome? What can cause ulnar nerve injury?
So long to pinky, here comes the thumb
Scaphoid, lunate, triquetrium, pisiform, hamate, capitulum, trapezoid, trapezium (trapezithumb)
Scaphoid in snuff box
Scaphoid most common fracture=avascular necrosis due to retrograde blood supply
Dislocation of lunate-->carpal tunnel
FOOSH--->hook of hamate damage leading to ulnar nerve injury.
What is carpal tunnel syndrome? Causes/associations? Symptoms? Pathophys?
Entrapment of median nerve in carpal tunnel leading to nerve compression
paresthesia, pain, and numbness in distribution of median nerve
Pregnancy, RA, Hypothyroidism, repetitive use
What is guyon canal syndrome? Usually cause?
Compression of ulnar nerve at wrist or hand
Cyclists due to pressure from handlebars
Describe the anatomy of the brachial plexus including which nerves originate from where.
Randy Travis Drinks Cold Beer
Roots, trunks, divisions, cords, branches
Roots of C5, C6, and C7 give off long thoracic
C5 root gives off dorsal scap nerve
C5 and C6 roots make up the upper trunk
Upper trunk gives off suprascapular nerve
All trunks give off anterior and posterior divisions
Anterior divisions of upper and middle trunk make up the lateral cord
All 3 posterior divisions make up posterior cord
Anterior division of Lower trunk make medial cord
Posterior cord gives off upper and lower subscapular nerves and thoracodorsal nerve
Lateral and medial cords give off lateral and medial pectoral nerves
Posterior cord gives off axillary nerve then becomes the radial nerve
Lateral cord and medial cord make up median nerve
Medial cord continues as ulnar nerve
Lateral cord continues as musculocutaneous nerve
What levels make up the axillary nerve? What will cause injury? What is the presentation?
Fractured surgical neck of humerus
Anterior dislocation of humerus
Loss of arm abduction at shoulder
Loss of sensation over deltoid muscle and lateral arm
What levels make up the musculocutaneous nerve? What will cause injury? Presentation?
Upper trunk compression
Loss of forearm flexion and supination
Loss of sensation over lateral forearm
What levels make up radial nerve? What will cause injury? Presentation?
Midshaft fracture of humerus
Compession of axilla due to crutches or arm over chair
Wrist drop: loss of elbow, wrist, and finger extension
Decr. grip strength (wrist extension necessary for max action of flexors)
Loss of sensation over post arm/forearm and dorsal hand
What levels make up median nerve? What will cause injury? Presentation?
Supracondylar fracture of humerus (proximal lesion)
Carpal tunnel and wrist laceration (distal)
Ape Hand and Popes Blessing
Loss of wrist flexion, flexion of lateral fingers, thumb opposition, lumbricals of 2nd/3rd digits
Loss of sensation over thenar eminence and dorsal and palmar aspects of lateral 3 1/2 fingers
Tinel sign (tingling on percussion) in carpal tunnel syndrome
What levels make up ulnar nerve? What will cause injury? Presentation?
Fracutre of medial epicondyle of humerus (funny bone) (proximal lesion)
Fracture hook of hamate (distal)
"Ulnar claw" on digit extension
Radial deviation of wrist upon flexion (proximal lesion)
Loss of wrist flexion, flexion of medial fingers, abductin and adduction of fingers (interossei), actions of medial 2 lumbrical muscles
Loss of sensation over medial 1 1/2 fingers including hypothenar eminence
What levels make up recurrent branch of median nerve? What will cause injury? Presentation?
Superficial laceration of palm
Loss of thenar muscle group: opposition, abduction, and flexion of thumb
No loss of sensation
Damage to these structures causes what?
Long thoracic nerve:
Upper trunk: Erb Palsy (waiter's tip)
Lower trunk: Claw hand (klumpke palsy)
Posterior Cord: Wrist drop
Long thoracic Nerve: Winged scapula
Axillary nerve: Deltoid paralysis
Radial nerve: Wrist drop
Musculocutaneous nerve: Difficulty flexing elbow, sensory loss
Median nerve: Decrease thumb function, Pope's blessing
Ulnar Nerve: Intrinsic muscles of hand, claw hand
What is the injury in Erbs palsy? Causes? Muscle deficit? Functional deficit?
Tractin or tear of upper trunk
Infants-lateral traction on neck during delivery
Adults-trauma (head forcefully away from shoulder)
Deltoid, supraspinatus (abduction-arm at side)
Infraspinatus (lateral rotation-arm medially rotated)
Biceps (flexion, supination-arm extended and pronated)
What is the injury in Klumpke palsy? Causes? Muscle deficit? Functional deficit?
Traction of tear of lower trunk
Infants: upward force on arm during delivery
Adults: Trauma-forceful pulling up on arm
Intrinsic hand muscles: lumbrical, interossei, thenar, hypothenar
Total claw hand: Lumbrical normaly flex MCP joints and extend DIP and PIP joints
What is the injury in thoracic outlet syndrome? Causes? Muscle deficit? Functional deficit?
Compression of lower trunk and subclavian vessels
Same as klumpke palsy
Atrophy of intrinsic hand msucles: ischemia, pain, and edema due to vascular compression
What is the injury in winged scapula? Causes? Muscle deficit? Functional deficit?
Long thoracic nerve
Axillary node dissectin after mastectomy
Inability to anchor scapula to thoracic cage
Cannot abduct arm above horizontal position.
What is the function of the lumbricals? What is the deficit like in proximal lesions? In distal lesions? Why?
Flex at MCP, extend at DIP and PIP joints
Distal: clawing, loss of lumbrical leads to extend MCP, flex IPs
Proximal: deficits less pronounced; seen during voluntary flexion of digits
What muscles are i the thenar eminence? Innervation? Hypothenar eminence? Innervation? function of dorsal interossei? Palmar?
Thenar: median nerve=opponens pollicis, abductor pollicis brevis, flexor pollicis brevis
Hypothenar (ulnar): opponens digiti minimi, abductor digiti minimi, flexor digiti minimi
DAB (dorsals abduct)
PAD (palmar adduct)
What spinal levels make up the obturator nerve? Cause of injury? Presentation?
Decr. thigh sensation (medial)
What spinal levels make up the femoral nerve? Cause of injury? Presentation?
Decr. thigh flexion and leg extension
What spinal levels make up the common peroneal nerve? Cause of injury? Presentation?
Trauma or compression of lateral aspect of leg
fibular neck fracture
Foot drop-inverted and plantarflexed at rest
Loss of eversion and dorsiflexion
Loss of sensation on dorsum of foot
Foot dropPED=Peroneal everts and dorsiflexes
What spinal levels make up the tibial nerve? Cause of injury? Presentation?
Baker cysts (proximal)
Tarsal tunnel syndrome (distal)
Inability to curl toes and loss of sensation on sole of foot
In proximal lesions, foot everted at rest with loss of inversion and plantar flexion
Can't stand on TIPtoes=Tibial Inverts and Plantar flexes
What spinal levels make up the superior gluteal nerve? Cause of injury? Presentation? Muscles
L4-S1=gluteus medius and minimus
Iatrogenic injury during intramuscular injection to upper medial gluteal region
Trendelenburg sign/gait-pelvis tilts b/c weight bearing leg cannot maintain alignment of pelvis through hip abduction. Lesion is CL to side that drops, ipsilateral to extremity on which patients stands.
What spinal levels make up the inferior gluteal nerve? Cause of injury? Presentation? Muscles?
Posterior hip dislocation
Difficulty climbing stairs, rising from seated position
Loss of hip extension
What is the function of the sciatic nerve? Spinal levels?
Function of pudendal nerve? Spinal levels? What is a landmark for local anesthetic during childbirth?
L4-S3-Innervates posterior thigh, splits into common peroneal and tibial nerves
S2-S4-innervates perineum. Ischial spine.
What is a lumbosacral radiculopathy? pathophys? Which nerve is affected in the pathophys? Waht are the findings with disc level L3/L4, L4/L5, L5/S1
Paresthesias and weakness in distribution of specific lumbar or sacral spinal nerves
Intervertebral disc herniation
Nerve association with inferior vertebral body is impinged.
L3/L4=weakness of knee extension, decr. patellar reflex
L4/L5=weakness of dorsiflexion, difficulty in heel walking
L5/S1=weakness of plantar flexion, difficulty in toe walking, decr. achilles reflex
Describe the steps of muscle conduction and contraction.
AP leads presynaptic voltage gates Ca channels to open, which releases NT
NT binds causing muscle cell depol in the motor end plate
Depol travels along muscle cell and down the T tubule
Depol of voltage sens dihydropyridine receptor couple to ryanodine receptor on sarcoplasmic reticulum induces conformation change, releasing Ca from SR
Ca binds troponin C, which causes tropomyosin to move out of myosin binding groove on actin filaments
Myosin releases bound ADP and PO4 leading to displacement of myosin on the actin filament (power stroke)
Myosin binds new ATP molecule causing detachment of head.
ATP hydrolyzes causing myosin head to cock, ready for next cycle.
What are the different lines and bands in skeletal muscle? What happens to them during contraction? What are t tubules? How many T tubules and terminal cisternae in skeletal muscle? Cardiac?
Z line-separates sarcomeres, place to which actin binds (capZ) and myosin (through titin) binds
I band=Just actin filaments (thin filaments), no thick
A band=Myosin filaments, overlapping actin filaments
H band=zone of thick filaments, not superimposed by thin filaments
M line=middle of sarcomere
When they contract, actin moves in towards M line, thus making the H bands and the I bands smaller, as well as the space between the Z lines shorter.
A band stays constant
T-tubules-extensions of plasma membrane juxtaposed with terminal cisternae. They are part of SR
In SM=triad=2 cist. 1 tubule
In CM=dyad=1 cist 1 tub
What is type 1 muscle? Speed? Color? Why? Action? type 2?
Incr mitochondria and myoglobin concentration
Incr. oxidative phoshorylation
White fibers resulting from decr. mitochondra and myoglobin conc
Describe the contraction and relaxation of a smooth muscle cell.
Action potential causes depol which activates L type voltage gated Ca channel on plasma membrane
Ca enters cell, binds to calmodulin, which activates MLCK, which phosphorylates myosin, allowing it to bind acting leading to contraction.
Nitric oxide activates guanylate cyclase which converts GTP into cGMP
cGMP activates myosin light chain phosphatase which dephosphorylates myosin leading to relaxation.
Describe endochondral ossification. Which bones? Which cells? When does woven bone occur in adults?
Bones of axial and appendicular skeleton and base of skull
Cartilaginous model of bone is first made by chondrocytes
Osteoclasts and blasts later relplace it with woven bone then remodel it to lamellar bone
Fractures and Pagets
Describe membranous ossification? Which bones?
Calvarium and facial
No cartilaginous, straight to woven bone then to lamellar
What is the function of osteoblasts? Origination? Osteoclasts? Origination?
blasts=build bone by secreting collagen and catalyzing mineralization.
Mesenchymal stem cells in periosteum
Clasts=multinucleated cells that dissolve bone by secreting acid and collegenases
What does PTH do to bones at low intermittent levels? At high levels?
Low: anabolic effects on osteoblasts and osteoclasts (indirect)
High: catabolic effects
What does estrogen do to bones? Deficiency?
Inhibits apoptosis in bone forming osteoblasts and induces apoptosis in bone resorbing osteoclasts
Excess cycles of remodeling and bone resorption leading to osteoporosis.
What is the pathophys of achondroplasia? Mutation/genetics? Symtpoms? Epid?
Failure of longitudinal bone growth (endochondral ossification--->short limbs
Membranous ossification is not affected---large head relative to limbs
Activation of FGFR3 inhibits chondrocyte proliferation
85% is sporadic
homozygous is lethal
Most common cause of dwarfism
What is primary osteoporosis? Lab values? Diagnosis? Causes? Presentations? What is type I? pathophys? type II? Epid? How can you prevent it? Treat it?
Trabecular (spongy) bone loses masa nd interconnections despite normal bone mineralization and lab values (serum Ca and PO4).
Diagnosed by bone mineral density test (DEXA) with a t score of 70 y.o.
Prevent: regular weight bearing exercise and adequate Ca and vitamin D intake throughout adulthood
Treatment: Bisphosphonates, PTH analogs, SERMs, rarely calcitonin; denosumab (RANKL antibody---against it)
What is osteopetrosis? Another name? Pathophys? Symptoms? Mutation? X ray? Complications? Treatment? Prognosis?
Marble Bone Disease
Carbonic anhydrase II mutation leads osteoclasts to have an inability to resorb bone (can't produce acid). Because of this, bone builds up.
Thickened dense bones, prone to fracture
Bone fills marrow space=pancytopenia and extramedullary hematopoesis
Xray-bone in bone appearance
CN impingment and palsies (narrowed foramina)
Bone marrow transplant (new osteoclasts).
What is the pathophys of osteomalacia and rickets? Symptoms? Lab findings?
Vit. D defic leads to osteomalacia in adults and rickets in children
Defective mineralization/calcification of osteoid
soft bones that bow out
Decr. Vit D leads to decr. serum calcium leads to incr. PTH secretion leads to decr. PO4
Hyperactivity of osteoblasts leads to incr. ALP (they require alkaline environment.
What is the pathophys of paget disease of bone? Histo? Another name? What are the stages? Symptoms? Complications? What does it incr. risk of? Lab values?
Common, localized disorder of bone remodeling caused by incr. in both osteoblastic and osteoclastic activity
Mixed: clasts and blasts
Quiescent: minimal of both
Serum Ca, PO4, and PTH levels normal
Mosaic pattern of woven and lamellar bone
Long bone chalk stick fractures
Hat size increased
Hearing loss common (auditory foramen narrow)
Incr bloow flow from incr. AV shunts may cause high output heart failure
Incr. risk of osteogenic sarcoma
What is the pathophys of osteonecrosis? Another name? Most common site? pathophys there? Causes?
Infarction of bone and marrow
Femoral head: medial circumflex femoral artery
Sickle Cell Disease
Caisson (the bends)
What is a giant cell tumor like? Cellularity? Location? Epid? X ray? Histo?
Locally aggressive benign tumor
Often around knee
Epiphyseal end of long bone
X-ray=soap bubble appearance
Multinucleated giant cells
What is an osteochondroma like? Epid? Possible risk?
Most common benign tumor (exostosis of the bone)
Mature bone with cartilaginous cap
Male < 25
Rarely transforms to chondrosarcoma
What is the epid of osteosarcoma? Ages? Predisposing factors? Location? x ray? Treatment?
2nd most common primary malignant bone tumor (behind multiple myeloma)
10-20 years old and >65
paget disease, bone infarcts, radiation, familial retinoblastoma, Li Fraumeni (p53 mutation)
Metaphysis of bone, near knee
Codman triangle (from elevation of periosteum) or sunburst pattern on xray
Aggressive. Surgical en bloc resection (with limb salvage) and chemo
What is the epid of ewing sarcoma? Location? Histo/grade? Treatment/prognosis? Mutation/result?
boys < 15 yo
Diaphysis of long bones, pelvis, scapula, ribs
Anaplastic small blue cell malignant tumor
onion skin periosteal reaction in bone
t(11;22) translocation causing fusion protein EWS-FLI 1
11 + 22=33 (patrick ewings number)
Compare and contrast osteoarthritis and rheumatoid arthritis concerning Etiology, joint findings, predisposing factors, classic presentation, and treatment.
OSTEO: mechanical, joint wear and tear destroys articular cartilage
RA: Autoimmune-inflamm destruction of synovial joints. Cytokines and Type III/IV HSR
OSTEO: subchondral cysts, sclerosis, osteophytes (bone spurs), eburnation (polished, ivory like appearance), synovitis, Heberden nodes (DIP), Bouchard nodes (PIP). No MCP involvement.
RA: Pannus (inflammatory granulation tissue) formation in joins (MCP, PIP), subQ rheumatoid nodules (fibrinoid necrosis), ulnar deviation of fingers, subluxation. Rare swan neck and boutonniere deform. Rare DIP involvement
OSTEO: Age, obesity, joint trauma
RA: Females > males. 80% have + RF (anti IgG Ab); anti-cyclic citrullinated peptide antibody is more specific. HLA-DR4
OSTEO: Pain in weight bearing joints after use (end of day), improves with rest. Knee cartilage loss begins medially (bowlegged). Non inflammatory. No systemic symptoms
RA: Morning stiffness lasting > 30 min and improving with use, symmetric joint involvement, systemic symptoms (fever, fatigue, weight loss, pleuritis, pericarditis)
OSTEO: Acetaminophen, NSAIDs, intraarticular steroids
RA: NSAIDS, steroids, disease modifying agents (methotrexate/sulfasalazine), biologics (TNF-alpha inhib)
What is pathophys of sjogrens like? Epid? Symptoms? lab findings? Etiology? Complications?
Autoimmune disorder characterized by destruction of exocrine glands (lacrimal and salivary) by lymph infiltrates
Inflammatory joint pain
xeropthalmia (decr. tear production leading to corneal damage
xerostomia (decr. saliva production)
Bilateral parotid enlargement
antinuclear antibodies SS-A (anti ro) and/or SS-B (anti-la)
What are some pathophysiologies of gout? Diagnosis? Symptoms? Precipitating factors? Acute treatment? Chronic? Epid?
Acute inflammatory monoarthritis caused by precipitation of monosodium urate crystals
Hyperuricemia caused by:
Underexcretion of uric acid (90% of pts)-usually idiopathic; can be exacerbated by medications (thiaz)
Overproduction (10%)-lesch nyhan, PRPP excess, incr. cell turnover, von Gierke disease
More common in males
Needle shaped and negative birefringent under polarized light (yellow under parallel light, blue under perpendicular).
Asymmetric joint distribution, usually MTP joint of big toe
Swollen, red, and painful
Tophus formation (external ear, olecranon bursa, or achilles tendon)
Acute attack after large meal or alcohol consumption (vies for secretion spots in kidney with urea)
Acute: NSAIDS, glucocorticoids, colchicine
Chornic: XO inhibitors (allopurinol, feboxostat)
What is the pathophys of pseudogout? Presentation? Location? Diagnosis? ASsociated diseases? Acute treatment? Prophylaxis? Epid?
Deposition of calcium pyrophosphate crystals within the joint space (chondrocalcinosis on x ray)
Pain and effusion in a joint, usually large joints (often knee)
Basophilic, rhomboid crystals that are weakly birefringent under polarized light (blue when parallel to light)
hemochromatosis, hyperparathyroidism, osteoarthritis
NSAIDS for sudden severe attacks; glucocorticoids
Colchicine for prophylaxis
What are 3 common causes of infectious arthritis? Symptoms?
S. aureus, streptococcus, and N. gonorrhoeae
Swollen, red, and painful joint
Synovitis, tenosynovitis, and dermatitis
What are seronegative spondyloarthropathies? Genetics? Epid? 4 examples?
Arthritis w/o rheumatoid factor (no anti-IgG antibody)
Strong association with HLA-B27
inflammatory bowel disease
What is the presentation like in psoriatic arthritis? Prevalence?
Joint pain and stiffness associated with psoriasis
Asymmetric and patchy involvement (only a few fingers)
Dactylitis (sausage fingers)
Pencil in cup deformity on xray
Fewer than 1/3 or psoriasis pts
What is the presentation/pathophys like in ankylosing spondylitis? x ray?
Chronic inflamm disease of spine and SI joints leads to ankylosis (stiff spine due to fusion of joints), uveitis, aortic regurgitation
Bamboo spine (vert fusion)
What often accompanies Crohns or UC?
Ankylosing spondylitis or peripheral arthritis
What is the class triad of reactive arthritis? Cause?
Conjuctivitis with anterior uveitis
Post-Gi (shigella, salmonella, yersinia, campylobacter
What is a basic classic presentation in SLE? Epid? What are some symptoms that can occur with SLE? Lab findings (what do they mean?)? What is libman sacks endocarditis? What types of nephritis occur? What are common causes of death in SLE? Treatment?
Rash, joint pain, and fever
Female of reproductive age
Rash (malar or discoid)
hematologic disorders (cytopenias)
Renal disease/Reynauds phenomenon
Immunosuppressants (to treat)
Neuro disorders (seizures/psychosis)
RASH OR PAIN
ANA (sens. not specific)
Anti-dsDNA=specific, poor prognosis (renal disease)
Anti-Smith (snRNPs)= specific, not prognostic
Antihistone antibodies=drug induced
Decr. C3/C4/CH50 (immune complex formation)
Non bacterial wart like vegetations on both side of valve
DPGN or membranous glomerulonephritis
NSAIDS, steroids, immunosuppresants, hydroxychloroquine
What is the etiology of antiphospholipid syndrome? How is the diagnosis made (symptoms/lab findings)? Treatment?
Primary or secondary (SLE) autoimmune disorder
History of thrombosis
Lupus anticoag (FP VDRL and prolonged PTT)
anticardiolipin (FP VDRL and prolonged PTT)
anti beta 2 GP antibodies
What is the pathophys of sarcoidosis? Lab findings? Epid? Presentation? xray? Associations (conditions it can cause)? Treatment?
Immune mediated widespread noncaseating granulomas
Elevated serum ACE levels
Elevated CD4/CD8 ratio
Often asymptomatic except for enlarged LNs
Bilateral adenopathy and coarse reticular opacities
Interstitial fibrosis, erythema nodosum, lupus pernio, Bell palsy, epithelioid granulomas containing microscopic schaumann and asteroid bodies, uveitis, hypercalcemia
What are the symptoms of polymyalgia rheumatica? Findings? Epid? Association? Treatment?
Pain and stiffness in shoulders and hips, often with fever, malaise, and weight loss
No muscle weakness
women > 50
Incr. ESR, Incr. CRP, normal CK
Rapid response to low dose corticosteroids
What are the symptoms of fibromyalgia? Treatment?
Chronic widespread MS pain associated with stiffness, paresthesias, poor sleep, fatigue
What are the lab findings in polymyositis and dermatomyositis? Treatmenet? What ist he presentation and pathophys of polymyositis? What is the pathophys and symptoms of dermatomyositis?
Incr. CK, +ANA, +Anti-Jo-1 AB, Anti SRP, Anti Mi 2 AB
Steroids followed by long term immunosuppressant therapy (methotrexate)
Progressive symmetric proximal muscle weakness, often in shoulders
Endomysial inflammation with CD8 T cells
Similar to poly, but with malar rash, gottron papules, heliotrope rash, shawl and face rash, mechanics hands.
Incr. risk of occult malignancy
Perimysial inflammation and atrophy w/ CD4 T cells
Compare and contrast myasthenia gravis with lambert eaton myasthenic syndrome concerning prevalence, pathophys, presentation, assocation, and response to AChEIs?
most common NMJ disorder
autoantibodies to postsyn ACh receptor
ptosis, diplopia, weakness
Worsens with muscle use
Thymoma, thymic hyperplasia
Reversal of symptoms
autoantibodies to presynaptic CA channel leads to decr. ACh release
proximal muscle weakness, autonomic symptoms (dry mouth, impotence)
Improves with muscle use
Small cell lung cancer
What is myositis ossificans? Location? Presentation?
metaplasia of skeletal muscle into bone following muscular trauma
Upper or lower extremity
Suspicious mass at site of known trauma or as incidental finding on radiography
What is the triad of scleroderma? Presentation? Describe the two types and associated antibody. Epid? Most common cause of death?
Triad of autoimmunity, noninflammatory vasculopathy, and collagen deposition with fibrosis
Sclerosis of skin (puffy, taut skin without wrinkles), fingertip pitting
Sclerosis of renal, pulmonary, CV, and GI systems
Diffuse: widespread skin involvement, rapid progression, early visceral involvement.
Anti Scl-70 AB=Anti DNA topoisomerase I
Limited: skin involvement confined to fingres and face
What are the 3 layers of skin? What are the five layers of the epidermis? What do they contain?
Epidermis, dermis, subQ fat (hypodermis)
Californians like girls in string bikinis
Strateum corneum (keratin)
stratum spinosum (desmosomes)
stratum basale (stem cell site)
What is a tight junction? Another name? Function? What is it made up of? Same questions for adherens junction, desmosome, gap junction, integrins, and hemidesmosome.
Tight: Zonula occludens=prevents paracellular movement of solutes. Claudins and occludins
Adherens Junction: Zonula adherens=below tight junction, forms belt connecting actin cytoskeletons of adjacent cells with CADherins (Ca depend Adhesion proteins).
Desmosome: Macula adherens-structural support via keratin interactions
Gap Junction: Channel proteins call connexons permit electrical and chemical communication b/w cells
Hemidesmosome: connects keratin in basal cells to underlying BM
Integrins: membrane proteins that maintain integrity of Basolateral membrane by binding to collagen and laminin in BM.
What is a macule? Example? Patch? Papula? plaque? Vesicle? Bulla? Pustule? Wheal? Scale? Crust?
Macule: flat lesion with well circumscribed change in color < 1cm=freckle, labial macule
Patch? macule > 1 cm=large birthmark
Papula? elevated solid skin lesion < 1cm=mole, acne
plaque? papule > 1 cm=psoriasis
Vesicle? Small fluid containing blister < 1 cm=chickenpox
\Bulla? large fluid containing blister > 1cm bullous pemphigoid
Pustule? Vesicle containing pus=pustular psoriasis
Wheal? transient smooth papule or plaque=hives
Scale? flaking off of stratum corneum=eczema, psoriasis, and SCC
Crust? dry exudate=impetigo
What is this? Example?
hyperkeratosis: incr. thickness of stratum corneum=psoriasis and calluses
parakeratosis:hyperkeratosis with retention of nuclei in stratum corneum=psoriasis
spongiosis:epidermal accumulation of edematous fluid in intercellular spaces=eczematous derm
acantholysis: separation of epidermal cells=pemphigus vulgaris
acanthosis: epidermal hyperplasia (incr. spinosum)=acanthosis nigricans
What is albinism? Pathophys? Other causes? Risks?
Normal melanocyte number with decr. melanin production due to decr. tyrosinase activity or defective tyrosine transport
Failure of neural crest cell migration
Incr. risk of skin cancer
What is melasma? Associations? What is vitiligo? Cause?
Hyperpigmentation associated with pregnancy or OCP use
Irregular areas of complete depigmentation caused by autoimmune destruction of melanocytes
Waht is acne? Pathophys? epid?
obstructive and inflammatory disease of the pilosebaceous unit predominantly found in the face and trunk
Adolescents most common
What is atopic dermatitis? Presentation? Associations?
Pruritic eruption, commonly on skin flexures
Asthma, allergic rhinitis
Starts on face in infancy then appears in antecubital fossae
What is the pathophys of allergic contact dermatitis? Causes?
Type IV HSR to nickel poison ivy or neomycin
What is a melanocytic nevus? risks? Intradermal presentation? Junctional presentation?
Common mole. Benign
Risk of melanoma
What is the presentation of psoriasis? Histology? What is auspitz sign? ASsociations?
Papules and plaques with silvery scaling (knees and elbows)
Acanthosis with parakeratotic scaling (nuclei still in corneum).
Incr. spinosum, decr. granulosum
Auspitz sign=bleeding when taking off scales (exposure to dermal papillae)
Nail pitting and psoriatic arthritis
What is rosacea? Pathophys/presentation? risk?
inflamm facial skin disorder characterized by erythematous papules and pustules but no comedones
Facial flushing to external stimuli
Rhinophyma (deformation of nose)
What is the presentation of seborrheic keratosis? Location? Pathophys? What is the leser trelat sign? Cause?
flat, greasy, pigmented squamous epithelial proliferation with keratin filled cysts
Looks stuck on (dark brown stuck on coin)
Head trunk and extremeties
Common benign neoplasm of older persons
Leser trelat=sudden appearance of multiple seborrheic keratoses, indicating underlying malignancy
What are verrucae? Cause? Histo?
Soft, tan colored cauliflower like papules
epidermal hyperplasia, hyperkeratosis, koilocytosis
What is urticaria? pathophys? Characterized?
Pruritic wheals that form after mast cell degranulationn
Superficial dermal edema and lymph channel dilation
What is impetigo like? Depth? Causes? Bullous impetigo?
S. aureus or S. pyogenes
Honey colored crusting
Same but with bullae=staph
What is cellulitis like? depth? Bug? Cause?
Acute painful spreading infection
Deeper dermis and subQ
S. pyogenes or S. aureus
Break in skin from trauma or other infection
What is erysipelas like? Depth? Bug?
Well defined demarcation between infection and normal skin
Upper dermis and superficial lymph
What is an abscess like? Depth? Cause?
collection of pus from walled off infection
deeper layers of skin
S. aureus (MRSA)
What is necrotizing fascitis like? Cause? Depth? Bug?
Bullae and purple color to skin
crepitus from methane and CO2 productionn
Flesh eating bacteria
S. pyogenes or anaerobic bacteria
What is the pathophys of staphylococcal scalded skin syndrome? Presentation? Epid?
Exotoxin destroys keratinocyte attachments in stratum granulosum only.
Fever and generalized erythematous rash with sloughing of the upper layers of the epidermis that heals completely
Newborns, children, adults with renal insufficiency
What is the pathophys of pemphigus vulgaris? Presentation? Locations? Diagnosis?
Potentially fatal autoimmunde skin disorder with IgG ab against desmoglein (part of desmosome)
Flaccid intraepidermal bullae caused by acantholysis (no desmosomes to hold stratum spinosum together)
Oral mucosa involvement
IF=Abs around epi cells in a netlike pattern
Nikolsky sign==separation of dermis upon manually stroking of skin
What is the pathophys of bullous pemphigoid? Presentation? Locations? Diagnosis?
Less severe than pemphigus vulgaris. IgG Ab against hemidesmosomes (bullow the epi)
Tense blisters containing eosinophils that affect skin but not oral mucosa
IF=Linear pattern at epi/derm junction
Nikolsky sign negative
What is the presentationn of dermatitis herpetiformis? Location? Pathophys? ASsociation?
Pruritic papules, vesicles, and bullae (often on elbows)
IgA at tips of dermal papillae
What are some associations with erythema multiforme? Presentation?
Infections (Myco, HSV), drugs (sulfa, beta lactams, phenytoin), cancers, autoimmune
Multiple types of lesions (macules, papules, vesicles, target lesions)
What are the symptoms of stevens johnson syndrome? Locations? Presentation? Assocation? What is toxic epidermal necrolysis? What is SJS-TEN? How is TEN different from staph scalded skin syndrome?
bullae formation and necrosis
Sloughing of skin
High mortality rate
2 mucous membranes involved
Targetoid lesions mmaybe
Adverse drug reaction
>30% of body surface = TEN ( destroys epi/derm junction, not just the stratum granulosum connections)
What is acanthosis nigricans? Location? Assocations?
Epidermal hyperplasia causing symmetric, hyperpigmented thickening of skin, especially in axilla or on neck.
Hyperinsulinemia (diabetes, obesity, cushing)
Visceral malig (gastric adenoCA)
What is actinic keratosis? Presentation? Risks involved?
Premalignant lesions caused by sun exposure.
Small rough erythematous or brownish papules or plaques
Risk of Squam cell CA proportional to degree of dysplasia
What is erythema nodosum? Associations?
Painful inflammatory lesions of subQ fat, usually on anterior shins.
Sarcoid, coccidiomycosis, histoplasmosis, TB, streptococcal infections, leprosy, crohns.
Presentation of lichen planus? Mucosal involvement? Histo? Assocation?
Polygonal, Planar Papules and Plaques
Wickham Striae (retic. white lines)
Sawtooth infiltrate of lymphocytes at dermal epidermal jucnitons
What is presentation of pityriasis rosea? Prognosis?
Herald Patch followed days later by other scaly erythematous plaques in a christmas tree distribution
Multiple plaques with collarette scale
6-8 weeks self resolve
What is a sunburn? Pathophys? What do UVA and UVB lead to? What can it lead to?
acute cutaneous inflammatory reaction due to excessive UV irradiation
DNA mutations, inducing apoptosis of keratinocytes
UVA=tanning and photoaging
Impetigo, skin cancers
Epid of Basal cell CA? Location? Spread? Typical Appearance? Other appearances? Histo?
Most common skin cancer
Sun exposed areas
Locallly invasive, no mets
Pink, pearly nodules, commonly with telangiectasias, rolled borders, central crusting or ulceration
Nonhealing ulcres with infiltrating growht
Squamous cell CA epid? Assocations? Location? Spread? Appearance? Histo? What is keratocanthoma like?
SEcond most common skin cancer
Excessive exposure to sunlight
Chronic draining sinuses
Sometimes arsenic exposure
Locally invasive, maybe to LNs, rare mets
Ulcerative red leasions with frequent scale
Face, lower lip, ears, hands
Variant that grows rapidly (4--6 weeks) and may regress spontaneously over months