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Flashcards in Week 5 Deck (41):
1

What are the determinants of gait

1. Pelvic drop - using hip abductors

2. Pelvic rotation

3. Knee flexion - reduces inertial change

4. Ankle joint and foot

5. Lateral displacement of body

2

Gluteus maximus deficit

i. Paralyzed non-functional extensors of the hip
ii. People will walk leaning back
iii. Can accompany paralyzed abductors
1. Lurch-tilt walk

3

Antalgic gait

i. Occurs with a painful hip or paralysis of abductor mm., primarily gluteus medius m.
ii. Determine competency by Trendelenburg test
iii. We normally walk with a positive Trendelenburg!

4

Quadriceps deficit

cannot extend knee so they put out a straight leg and “vault” over

5

Anterior leg deficit (foot drop)

cannot dorsiflex which results in “foot drop” so they walk with a high step to clear foot
-damage to common fibular n.

6

What anchors actin cytoskeleton to sarcolemma

Dystrophin

7

Subneural clefts at the NMJ

-Crests vs troughs

Crests - Ach gated channels

Trough - Voltage gated Na+ channels

8

Dantrolene MoA

blocks RyR1 (ryanodine-1 receptor)
-calcium release channel

9

DHP-ryanodine receptor interaction
-where are each located

DHP -> on T-tubule
Ryanodine -> on terminal cisternae of sarcoplasmic reticulum

2 ways for calcium release in to sarcoplasm

-mechanical couple of DHP-Ryanodine receptors (MAJOR)

-activation of ryanodine receptor by release of Ca++ from DHP receptors (nor required in skeletal muscle)

10

Components of thin and thick filaments

THIN FILAMENTS
-actin
-tropomyosin
-troponin

THICK
-myosin

11

Role of calsequestrin

Binds Ca++ in the SR to prevent buildup

12

Role of ATP in muscle contraction

-causes dissociation of myosin head from actin

-hydrolyzes to place myosin head back into cocked state

13

What cause the power-stroke

release of phosphate from myosin head

14

Type 1 vs Type II fibers

Type 1
-slow twitch
-lots of mitochondria
-low glycogen content

Type IIa+b
-fast twitch
-low mitochondria
-high glycogen content

15

Stains for muscles fibers
1. Trichome
2. Succinate DH
3. ATPase at pH 4.6
4. ATPase at pH 10

1. Mitochondria and myelin
2. Complex 2 of respiratory chain
3. Type I is darkest IIa is the lightest
4. Type I is light and Type II is dark

16

Only muscular dystrophy to show inflammation

Fascioscapulohumeral MD

17

Which muscular dystrophy has high incidence of cardiomyopathy

Becker's

18

Duchenne:
Age of onset
Presentation
Labs

1. 2-5 y/o
2. Pelvic girdle weakness and calf pseudohypertrophy due to fat infiltration and fibrosis
3. Highly elevated CPK

19

Which inflammatory myopathy is associated with perifascicular atrophy?

Dermatomyositis

20

What are the inclusions seen with Inclusion Body Myositis

Which inflammatory cells?

basophilic inclusions containing beta amyloid and phosphorylated tau protein

T cells and macrophages in endomysium and perimysium

21

Onset Peaks for inflammatory myopathies

1. 5-14 y/o

2. 50s - specially inclusion body myositis

22

2 skin findings associated w/ dermatomyositis

1. Grotten lesions - scaling erythematous eruption or patches over knuckles, elbows and knees

2. Heliotrope discoloration of eyelids

23

Compare inflammations b/w
-Dermatomyositis
-Polymyositis

1. Dermatomyositis
-Skin, muscle, GI
-risk of GI ulceration and bleeding

2. Polymyositis
-no skin lesions
-inflammation in heart, lungs and blood vessels

BOTH STAIN POSITIVE FOR MHC-1

24

Which muscles are affected w/ inclusions body myositis

distal muscles (extensors of knee and flexors of wrist and fingers)

25

70% of ankle fractures classified as

Supination-external rotation

26

Syndesmosis

Relationship b/w fibula and tibia

27

Describe pilon fractures

1. There is articular involvement
2. Really bad ankle fractures
3. External fixator whiles waiting for swelling to come down
4. CT scan will give best pic of bone

28

Gold standard for ankle arthritis

Arthrodesis - fusion of tibia to talus

29

What accompanies calcaneus fractures often

Which type of calcaneal fracture is surgical emergency

Spinal injury

Tongue type - skin on posterior heel will die

30

Risk of what w/ talus fracture?

Necrosis

31

Describe LisFranc injuries and tx

1. Tarsal-metatarsal joint
2. Usually 1st and 2nd MT bases
3. Almost always fixed surgery
a. Anatomic reduction
b. Stable fixation

32

Pes Planovalgus
-definition
-most common cause
-presentation
-management

1. flatfoot
2. Posterior tibial tendon dysfunction (IMPORTANT)
3. Too many toe signs for PTTD

MANAGEMENT
iv. Treat early and if there is flexibility
1. Orthotics
v. Later but still flexible
1. Surgical options

33

Adult Cavovarus

i. Opposite of flat foot
ii. High arch
iii. Lateral ankle and foot pain b/c their walking on lateral border of foot
iv. Roll their ankle a lot
v. Peek a boo heel sign
1. Can see heel from front

34

Hallux valgus (Bunion)
-describe
-management

i. Lateral deviation of the great toe on the 1st metatarsal
b. More common in women because of shoes
c. Only surgical fix if there is pain
i. Start with changing shoe
ii. Recovery time is almost a year

35

Goal of ankle fracture treatment

reduced, stable, healed ankle

36

Overpull of what 2 tendons contributes to adult cavovarus

Posterior tibial and fibularis longus tendons

37

Pemphigus vulgaris vs Bullous pemphigoid

BOTH
-Type II hypersensitivity
-corticosteroids and other immunosuppressive drugs to tx

PV
-abs against desmosomes that hold keratinocytes together
-Intrapidermal -> flaccid bullae

BP
-Abs against BM
-subepidermal -> tense bullae
-eosinophils in dermis w/ subepidermal blister
-old people

38

Leukocytoclastic vasculitis
-which hypersensitivity?

Type III - immune complex leading to vessel wall damage

39

Allergic contact dermatitis
-which hypersensitivity?

Type 4

40

Differential for allergic contact dermatitis

- Other forms of Dermatitis
• Atopic – distribution, family and personal history of atopy, age of onset
• Seborrheic – location, greasy flaking, less pruritus

– Tinea Corporis – annular, KOH + patches

– Psoriasis – distribution, morphology of papules and plaques (vs. patches in dermatitis)

41

Psoriasis vulgaris presentation

– Well-defined pink to red papules and plaques
– Thick white to silvery scale
– Auspitz sign – pinpoint bleeding with lifting of scale – Elbows, knees, scalp, nails, buttock
– Can involve 100% of body surface area