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Flashcards in Musculoskeletal + Skin Deck (102):
1

Osteomyelitis in kids usually seeds where?

Metaphysis of long bones

2

Dystonia - definition and cause

Prolonged repetitive muscle contractions.
Occurs as a result of impaired basal ganglia function.

3

Safest location for a intragluteal injection?

Superolateral region - avoids the sciatic nerve and the superior gluteal nerve

4

Complications of ankylosing spondylitis (3)

-Limited chest expansion
-Ascending aortitis
-Uveitis

5

Compliment deficiency in SLE

Decrease in C3, C4, CH50

6

Mechanism of C. perfringens necrosis

Lecithiniase/alpha-toxin/Phospholipase C

splits phospholipid molecules resulting in membrane destruction, cell death, hemolysis and necrosis

7

HLA-B27 is what class of HLA (I vs II)?

Class I serotype - present on all nucleated cells

8

DDx: back pain + elevated alkaline phosphatase = (2)

-Osteoblast metastasis
-Paget's disease of bone

9

anti-histidyl-tRNA transferase autoantibody =

Anti-Jo-1 antibody

polymyositis/dermatomyositis

10

bony deformities + hyperthyroidism + unilateral, large, irregular pigmented macules =

McClune Albright Syndrome

11

Definition - heteroplasmy

Coexistence of both mutated and wild type versions of mitochondrial genomes in one cell

12

Lactic acidosis + Histological ragged red fibers =

Mitochondrial myopathy

13

Bugs that cause necrotizing fascitis (3)

-Strep pyogenes (Group A Strep)
-Staph aureus
-Clostridium perfringens

14

What is a "contracture" of a wound?

excessive metalloprotease (MMP) activity that results in excessive wound contraction

15

Muscle involved in the valsalva maneuver that develops the elevated intra-abdominal and intra-thoracic pressure =

Rectus muscle

16

Differences in stature in achondroplasia vs GH/IGF-1 deficiency

Achondroplasia = short, thick appendicular skeleton with a normal axial skeleton - disproportional short stature

GH/IGF-1 deficiency = proportional short stature

17

Tendons that line the anatomical snuff box (3)

-Tendon of the extensor pollicis longus - medial border
-Tendon of the abductor pollicis longus - lateral border
-Tendon of the extensor pollicis brevis - lateral border

18

What kind of damage does UV light do to DNA?

pyrimidine dimers

19

What childhood exanthem has a maculopapular rash that begins on the face and quickly spreads down to extremities and trunk with co-presenting post-auricular and occipital lymphadenopathy

Rubella (part of the Togavirus family)

20

Intellectual disability + Gait/Posture disturbances + Eczema + Musty body odor =

Phenylketonuria (autosomal recessive)

21

What hormone is responsible for male pattern baldness?

DHT

"androgenic allopecia"

22

What causes the skin retraction seen in invasive breast cancer?

Infiltration of the suspensory Cooper ligament

23

What causes the peau d'orange appearance in invasive breast cancer?

Blockage of lymphatic drainage

24

Chronic glucocorticoid use to treat atopic dermatitis results in what (negative) side effect?

atrophy of the dermis caused by decreased ECM collagen and GAG production

25

First line treatment for someone having a gouty arthritis attack?

NSAIDs

26

Artery damaged during displacement of the femoral neck?

medial circumflex artery

27

How do you measure potency of an inhaled anesthetic?

MAC = minimal alveolar concentration

Inversely proportional to potency:
-low MAC
-increased potency

28

elderly patient + pulmonary TB + isoniazid treatment = peripheral neuropathy

Why?

Vitamin B6 deficiency caused by isoniazid use.
Requires pyridoxine supplementation.

29

Older patient + new back pain + recent/treated Staph bacteremia infection + fever + fatigue + malaise =

How to dx?

Vertebral osteomyelitis - probably from the Staph infection

to dx = MRI of the spine

30

Child with sickle cell disease + fever + pain in foot + leukocytosis =

Osteomyelitis (Salmonella typhi)

Avascular necrosis would present as bone pain only

31

40 year old African American woman, fever, malaise, bilateral hilar adenopathy, erythema nodosum, elevated serum Ca =

Sarcoidosis (African american woman + hilar adenopathy)

Elevated level of 1,25 dihydroxycholecalciferol (active vitamin D due to the presence of alpha1 hydroxylase in the epithelioid macrophages)

32

7 causes of erythema nodosum

-Sarcoidosis
-Coccidiomycoses
-Histoplasmosis
-TB
-Leprosy
-Strep infections
-Inflammatory Bowel Disease

33

Male newborn with macrocephaly + poor skull mineralization + misshapen long bones + fractures that occurred during birth =

Osteogenesis imperfecta - decreased collagen type I production

34

Hyperreflexia is seen in a lesion of the UMN or LMN?

UMN lesion leads to hyperreflexia

35

What childhood exanthem has a rash that begins at the head and travels downward but is preceded by cough + conjunctivitis + spots in the mouth?

Measles (part of the Paramyxovirus family)

36

"trabecular thinning of bone"

Osteoporosis

37

"persistence of primary unmineralized spongiosa in the medullary canals"

Osteopetrosis

38

6 P's of lichen planus =

Purple
Puritic
Polygonal
Planar
Papules
Pustules

39

3 arm nerves that are flexors =

Musculocutaneous (C5-C7)
Median (C5-T1)
Ulnar (C8-T1)

40

2 arm nerves that are extensors =

Axillary (C5-C6)
Radial (C5-T1)

41

Lab values (serum Ca, PTH, PO4)

Osteoporosis =
Paget's disease of the bone =
Osteopetrosis =

All normal!

Paget's disease will have increased ALP due to last stage being osteoblast-heavy

42

Weakness in hands and heaviness in eyelids by the end of the day + anterior mediastinal mass

Myasthania gravis + associated thymoma or thymic hyperplasia

43

Diseases caused by defective DNA break repair mechanisms (6)

-Xeroderma pigmentosum
-Carcinogenesis
-Hereditary nonpolyposis colorectal cancer (HNPCC)
-Ataxia telagiectasia
-Fanconi anemia (-> aplastic anemia)
-Bloom syndrome

44

Recurrent sinopulmonary infections + superficial blanching nests of distended capillaries + atrophied cerebellum + child =

Ataxia telagiectasias

superficial blanching nests of distended capillaries = telagiectasias

45

Rash on palms and soles and body = (4)

-N. meningitidis
-Coxsackie A
-Rocky mountain spotted fever
-Syphilis (secondary)

You drive Nice CARS with your hands and feet.

46

Man with an inflamed, red knee. Aspirate has crystals and increased WBC with neutrophilic predominance.

Pseudogout with Calcium pyrophosphate crystals

47

Cytokines important in granuloma formation = (3)

-IL-12
-IFN-gamma
-TNF-alpha

48

Sensory innervation of the musculocutaneous nerve

Musculocutaneous nerve (C5-C7) -> lateral cutaneous nerve of the forearm -> lateral forearm sensation

49

Posterior arm + Posterior forearm + Dorsal hand sensory

Posterior cutaneous branches of the radial nerve

50

Anterior forearm, medial forearm, and anterior arm sensation

Medial antebrachial cutaneous nerve - branch off the median cord of the brachial plexus

51

Trendelenburg gait - damage to inferior or superior gluteal n?

Superior gluteal nerve - gluteus minimus, medius and tensor fascia latae muscle

52

Difficulty rising from seated and difficulty climbing stairs - damage to inferior or superior gluteal n?

Inferior gluteal nerve - gluteus maximus muscle

53

Asteroid body is found in

Sarcoidosis

54

Main cell type in the pathology of polymyositis.

Where is the inflammation located?

CD4 T cells -> endomyseal inflammation

55

Main cell type in the pathology of dermatomyositis.

Where is the inflammation located?

CD8 T cells -> perimyseal inflammation

56

2 mechanisms of albinism:

-Decreased tyrosinase activity
-Defective tyrosine transport

Overall, decreased melanin synthesis

57

Autoimmune destruction of melanocytes

Vitligo

58

Type of gland:
Salivary =
Sweat glands =
Mammary gland =
Sebaceous gland =
Meibomian gland (eyelid) =

-Salivary = merocrine
-Sweat glands = merocrine
-Mammary gland = apocrine
-Sebaceous gland = holocrine
-Meibomian gland (eyelid) = holocrine

59

Mutation in xeroderma pigmentosum

Defective UV-specific endonuclease

60

Twisted ankle inwards + pain and ecchymoses on anterolateral ankle + can still walk unassisted =

Tear of the anterior talofibular ligament

61

two locations of collagen synthesis

-RER of fibroblasts
-ECM

62

Serum _ measures osteoblast activity

ALP

63

Urinary _ measures osteoclast activity

Deoxypyridinoline

64

Family history of hypermobile joints + susceptible to easy bruising + hyperelastic skin

Ehlers-Danlos Syndrome

65

Cytokine responsible for keloid production/growth

TGF-beta

66

Hartnup disease treatment

Niacin

Most of the symptoms are due to tryptophan deficiency (-> niacin deficiency)

67

Positive lepromin skin test indicates _a_ cell response with _b_ (3) cytokines and a _c_ bacterial load.

a=Th1
b=IL-2, IFN-gamma, IL-12
c=low

68

Negative lepromin skin test indicates _a_ cell response with _b_ (3) cytokines and a _c_ bacterial load.

a=Th2
b=IL-4, IL-5, IL-10
c=high

69

Latissimus dorsi does medial/lateral rotation of the humerus. Innervated by _.

Medial rotation of the humerus

Innervated by thoracodorsal nerve (T7-T12)

70

Metastases to bone - osteoblastic/sclerotic (3)

-Prostate
-Small cell lung
-Hodgkin lymphoma

71

Metastases to bone - osteolytic (5)

-Multiple myeloma
-Non-small cell lung
-Non-hodgkin lymphoma
-Melanoma
-Renal cell carcinoma

72

Metastases to bone - both osteoblastic and osteolytic (2)

-GI
-Breast

73

What bone tumor:
-elevation of the periosteium
-may be associated with other familial cancers
-bimodal age distribution

Osteosarcoma
-Codman's triangle - elevation of the periosteium due to the tumor being located on the edge
-Sunburst pattern on xray
-Associated with Rb/Li Fraumeni
-Occurs in young and elderly

74

What bone tumor is associated with t(11;22)

Ewing Sarcoma
-occurs in boys less than 15 yo
-diaphysis of bone
-onion skin periosteal reaction
-small blue cell malignant tumor

75

What bone tumor has bone pain that resolves with aspirin use and is found on the diaphysis?

Osteoid osteoma

76

What bone tumor has pain that does not resolve with aspirin use and is found in the vertebrae.

Osteoblastoma

77

Young boy with frequent fractures from minimal trauma + anemia + target RBCs

Osteopetrosis - defective osteoclasts

Mutation may be in carbonic anhydrase II therefore impairing the ability of osteoclasts to generate the acidic environment needed

78

Sawtooth infiltrate of lymphocytes at the dermal-epidermal junction

Lichen planus

(Associated with HepC)

79

54 year old woman with a past history of radical mastectomy and chronic lymphedema. Presents with multiple violaceous nodules on her arm.

Cutaneous angiosarcoma
-CD31+
-infiltration of the dermis with slit-like abnormal vascular spaces
-vascular tumor that commonly arises post-chronic lymphedema

80

Procollagen peptidase action in collagen synthesis

Cleavage of disulfide-rich terminal regions of procollagen
Occurs in the ECM

This is inhibited in EDS

81

Irritant found in poison ivy, poison oak, poison sumac

Urushiol

82

Cell type responsible for linear growth

Chondrocytes - produces the cartilaginous matrix in the physis/growth plate

"Endochondrial ossification"
-controlled by FGF3

83

Urticaria on light microscopy

Dermal edema caused by increased vascular permeability

84

RA can involve what part of the vertebral column?

Cervical spine

85

Reactive arthritis follows what 2 types of infections?

-Genitourinary or Enteritis (GI)
-Clinical manifestations are due to immune complexes that form involving bacterial antigens (even though the joint aspirates are sterile)

86

Genetics of achondroplasia

AD
Gain of function mutation in FGF Receptor 3
Associated with advanced paternal age

87

What substance is responsible for increasing the reaction rate in skeletal muscle contraction?

Calcium

Stimulates phosphorylase kinase -> activates glycogen phosphorylase-a by phosphorylating it -> turns glycogen into G1P -> ATP!

88

Causes of bilateral carpal tunnel syndrome (5)

-Pregnancy - fluid accumulation
-Hypothyroidism - glycosaminoglycan build up
-Diabetes Mellitus - connective tissue thickening
-Rheumatoid Arthritis - tendon inflammation
-Chronic hemodialysis - beta-2 microglobulin deposition

89

These are types of _
-superficial spreading
-nodular
-lentigo maligna
-acral lentiginous

melanoma

90

Rheumatoid factor is _

IgM autoantibody that targets the Fc portion of IgG

91

what effect does osteoporosis have on osteoclast activity, RANK L concentration and osteoblast concentration?

Low estrogen -> osteoporosis

low estrogen ->
-increases osteoclast activity
-increases RANK-L concentration
-decreases osteoblast concentration due to increasing turn over

92

Osteomalacia cause?

Caused by decreased vitamin D

93

diabetic neuropathy pain?

burning pain

94

What tumor is often associated with Paget’s disease of the bone?

Osteosarcoma

95

Globus sensation/hystericus/pharyngeus

Abnormal sensation of a foreign body/tightness in the throat

Worse when swallowing saliva, alleviated when swallowing food or liquid

Functional disorder

96

Removing _ from ECF will cause cadherins to dissociate

Calcium

Cadherins are calcium-dependent

(cell)-cadherin-cadherin-(transmembrane protein-filament)

97

Posteriorly dislocated tibia most commonly injures the _

Popliteal artery
-It is located deep within the popliteal fossa and is susceptible to tearing by traction (anterior or posterior dislocation)

(anterior)-bones-popliteal artery-popliteal vein-tibial nerve-(posterior)

98

Patient had a chest tube put in and now she cannot raise her R arm above her head and when pushing against a wall, the R scapula protrudes. What nerve and muscle?

Long thoracic nerve is damaged resulting in damage to serratus anterior

99

Articular cartilage is made of

Type II collagen

Also made of type II collagen = all other cartilage, vitreous body, nucleus pulposus

100

Red safranin O stain, stains what 3 things red

-Cartilage
-Mast cell granules
-Mucin

101

What is the lens made out of?

Type IV collagen

Also made of type IV collagen = basement membrane, basal lamina

102

What is the only unmyelinated efferent nerve?

Autonomic postganglionic nerve

Other group C nerves:
-Afferent neurons that conduct heat, slow onset dull burning/visceral pain
-Primary bipolar sensory neurons