HCP 1 Flashcards
Damaged ulnar nerve will affect what muscles of the hand?
- adductor pollicis
- adductor digiti minimi
- flexor digiti minimi (brevis)
- opponens digiti minimi
- three palmar interosseous muscles
- four dorsal interosseous muscles
Action of adductor pollicis
adducts thumb
action of adductor digiti minimi
abducts 5th digit
action of flexor digiti minimi (brevis)
flexes proximal phalanx of 5th digit at MCP
action of opponens digiti minimi
5th digit opposition with thumb
action of 3 palmar interosseous muscles
adducts digits; PAD (palmar adduct)
action of 4 dorsal interosseous muscles
abducts digits; DAB (dorsal abduct)
Sensory effects of damaged ulnar nerve will affect where?
medial edge of palm; 4th and 5th digit
If the common peroneal nerve were affected what other nerves would be affected distally?
deep fibular (peroneal) nerve (anterior leg) superficial fibular (peroneal) nerve (lateral leg)
Damaged deep fibular (peroneal) nerve would affect what muscle?
Tibialis anterior
Extensor Hallucis longus
Extensor digitorum longus
Damaged superficial fibular (peroneal) would affect what muscle?
Fibulas (peroneus) longus
Fibulas (peroneus) brevis
action of Tibialis anterior
dorsiflexes foot at ankle and inverts foots
action of Extensor Hallucis longus
extends great toe, dorsiflexes foot at ankle
action of Extensor digitorum longus
extends lateral four digits and dorsiflexes foot at ankle
action of Fibulas (peroneus) longus
everts foot and weakly plantar flexes ankle
action of Fibulas (peroneus) brevis
everts foot and weakly plantar flexes ankle
Sensory affects due to damage to deep fibular (peroneal) nerve would be
decreased sensation to anterior leg and between 1st and 2nd digit of foot
Sensory affects due to damage to superficial fibular (peroneal) nerve would be
decreased sensation to lateral leg and dorsum of foot
Clinical manifestation of damage to common fibular (peroneal) nerve would be
foot drop, inability to dorsiflex foot upon ambulation leading to foot dragging on the ground
Also, difficulty standing on affected foot d/t weak eversion of foot
Clinical manifestation of damage to ulnar nerve would be
loss of grip strength, unable to coordinate digits especially 5th digit
Unable to abduct or adduct fingers
unable to flex or adduct wrist
A granuloma consists of what cells?
- multinucleate giant cells (fused macrophages)
- epitheloid histiocytes (morphologically differentiated macrophages)
- fibroblasts
- T cells
- Lymphocytes (i.e. neutrophils)
What causes a central zone of necrosis in granulomas?
reactive oxygen species
Hypoxia
What cytokines mediate tuberculoid leprosy and what do those cytokines do?
IL-2 (secreted by Th1 cells ➡️ further increase differentiation of Th0 to Th1
INF-gamma (leads to classically activated macrophages, increase differentiation of Th0 to Th1)
IL-12 (secreted by APC, increase differentiation of Th0 to Th1)
What cytokines mediate lepromatous leprosy and what do those cytokines do?
IL-4 and IL-13 (secreted from APC to Th2 cell ➡️ alternatively activated macrophages)
IL-10 (secreted by alt macs ➡️ suppression of Th1 response)
Jak/STAT pathway for lepromatous leprosy where APC secretes IL-4 or IL-13
IL-4 or IL-13 binds to Th0 cytokine receptor ➡️ dimerization of Th0 cytokine receptor ➡️ phosphorylates JAK ➡️ JAK mediated phosphorylation of STAT6 ➡️ STAT6 dimerizes ➡️ translocates to nucleus ➡️ increased transcription of GATA3 ➡️ inhibits T-bet ➡️ increased suppression of Th1 cells and increased Th2 cell proliferation
Jak/STAT pathway for tuberculoid leprosy where APC secretes IL-12
IL-12 binds to Th0 cytokine receptor ➡️ dimerization of Th0 cytokine receptor ➡️ phosphorylates JAK ➡️ JAK mediated phosphorylation of STAT4 ➡️ STAT4 dimerizes ➡️ translocates to nucleus ➡️ increased transcription of T-bet ➡️ inhibits GATA3 ➡️ increased suppression of Th2 cells and increased Th1 cell proliferation
Jak/STAT pathway for tuberculoid leprosy where APC secretes INF-gamma
IFN-gamma binds to Th0 cytokine receptor ➡️ dimerization of Th0 cytokine receptor ➡️ phosphorylates JAK ➡️ JAK mediated phosphorylation of STAT1 ➡️ STAT1 dimerizes ➡️ translocates to nucleus ➡️ increased transcription of T-bet ➡️ inhibits GATA3 ➡️ increased suppression of Th2 cells and increased Th1 cell proliferation
Mechanism of hypo pigmentation in tuberculoid leprosy
classically activated macrophages release ROS while granuloma encapsulates dermal/stratum basale layer cells (hypoxia) ➡️ creates a central zone of necrosis in granuloma ➡️ destruction of melanocytes ➡️ decreased production of melanosomes locally ➡️decreased uptake of melanosomes in keratinocytes locally ➡️ decreased melanin ➡️ hypopigmentation
Damaged ulnar nerve will affect which muscles of the forearm?
- flexor carpi lunaris
2. medial half (digits 4 and 5) of flexor digitorum profundus
Motor function of flexor carpi ulnas
Alone flexes & adducts wrist simulataneously
Flexes wrist with flexor carpi radialis
adducts wrist with flexor extensor carpi ulnaris
motor function of flexor digitorum profundus
Only muscle that can flex DIP joints of digits
Flexes distal phalanges of medial four digits after flexor digitorum superficialis has flexed their middle phalanges “curls fingers”
assists with flexion of hand- “making fist”
