MSK Flashcards
Order of carpal bones (lat to med by row)
scaphoid/lunate/triquetrum/pisiform
trapezium/trapezoid/capitate/hamate
Rotator cuff muscles and action
Supraspinatus-abduct
Infraspinatus-lat rotation
Teres minor-adduct/lat rotation
Subscapularis-adduct/med rotation
Brachial plexus segments
Roots-C5 to T1 Trunks-upper/mid/lower (Erb-Duchenne/Klumpke's lesion) Divisions Cords-lat/post/medial (wrist drop) Branches-MC/median/ulnar
Brachial plexus protection from clavicle fracture
Subclavius muscle
Dislocation of humeral head
unable to abduct the arm
Axillary n. (C5/C6)
dislocation or surgical neck fracture
Midshaft humeral fracture
unable to extend wrist
Radial n. (C5-T1)
brachioradialis/supinator/triceps/extensors
post arm/dorsal thumb & hand sensory deficit
Fracture of supracondylar humerus
unable to grab objects with hand
weak wrist flexion
Median n. (C5-C8, T1)
opposition of thumb/lat finger flexion/wrist flexion
palmar lat hand sensory deficit
Ape Hand/Pope’s blessing
Fracture of medial epicondyle of humerus
weak wrist flexion
Ulnar n. (C8, T1)
medial finger flexion/wrist flexion
hypothenar eminence sensory deficit
radial deviation on wrist flexion
Traumatic delivery of newborn
No abduction/lat rotation/pronation
Erb-Duchenne palsy
C5/C6 upper trunk
Thenar/hypothenar eminence atrophy
sensory deficit on medial forearm/hand
Klumpke’s palsy
C8/T1 inf trunk
Lesion with ulnar claw
loss of medial lumbrical function
cannot extend 4th/5th digits
due to ulnar nerve
Lesion with median claw
dislocated lunate/carpal tunnel
cannot extend 2nd/3rd digits
distal median n.
Pope’s blessing lesion
proximal median n. lesion
loss of lat finger flexion/thumb opposition
Ape hand lesion
proximal median nerve lesion
loss of opponens pollicis m. fxn
Winged scapula
lymphedema on ipsilateral side
Long thoracic n. (C5-C7)
loss of serratus ant fxn
Hand muscles innv by median n.
Opponens pollicis
abductor pollicis brevis
flexor pollicis brevis
Hand muscles innv by ulnar n.
Opponens digiti minimi
abductor digiti minimi
flexor digiti minimi
Loss of thigh adduction
obturator (L2-4) n.
ant hip dislocation
Loss of thigh flexion/leg extension
femoral (L2-4) n.
pelivc fracture
Foot drop
Common peroneal (L4-S3) knee trauma
Loss of thigh abduction
Sup gluteal (L4-S1) post hip dislocation
Trouble walking up stairs
can’t jump
Inf gluteal (L5-S2) post hip dislocation
Which band of sarcomere shortens with contraction?
H and I bands
A band remains constant
Skeletal m. contraction sequence
depolarization moves down T tubule
voltage sensitive dihydropyridine receptor/ryanodine receptor releases SER Ca2+
Ca2+ binds troponin C/myosin free to bind
mysosin releases ADP/power stroke
Fast twitch muscles
white color
anaerobic glycolysis
decreased myoglobin/mitochondria
Endochondral ossification
in axial/appendicular skeleton/base of skull bones
cartilage made first by chondrocytes
later replaced by lamellar bone (via osteoblasts/osteoclasts)
Membranous ossification
facial/calvarium bones
woven bones formed directly
47 y/o male
growth on tibia
glistening mass in medullary cavity
chondrosarcoma
malignant
Estrogen’s role in bone formation
inhibits apoptosis of osteoblasts
induces apoptosis of osteoclasts
AD
short limbs/lg head
assc with older father
Achondroplasia
FGFR3 mutation constitutive expression
Calcinosis Raynaud's dysphagia sclerodactyly telangiectasia
CREST syndrome
esophageal dysmotility (dysphagia)
anti-Centromere Ab
Thick, dense bones
multiple fractures
pancytopenia
facial n. palsy
Osteopetrosis/marble stone disease
defective osteoclasts
mutation of carbonic anhydrase II
bone marrow space filled (pancytopenia)
Bowing bones
increased alkaline phosphatase
Osteomalacia/rickets (in children)
Vit D deficiency
defective mineralization
hyperactivity of osteoblasts
Increased ALP
Mosaic bone pattern
chalk stick fractures
Paget’s disease of bone
hyperactivity of osteoblasts & osteoclasts
increased AV shunts and osteogenic sarcoma
Osteitis fibrosa cystica
overproduction of PTH
brown tumors of hyperparathyroidism
25 y/o
growth at epiphyseal end of femur
double bubble/soap bubble on x-ray
Giant cell tumor (osteoclastoma)
spindle shaped cells with multinculeated giant cells
benign tumor
16 y/o male
growth at the knee
metaphysis of femur
pt has Paget’s disease
Osteosarcoma (osteogenic sarcoma)
Sunburst pattern on x-ray
malignant tumor
Codman’s triangle
11 y/o male
onion skin appearance of bone
diaphysis of femur
Ewing’s sarcoma
highly aggressive
assc with t(11,22) translocation
47 y/o male
growth on tibia
glistening mass in medullary cavity
chondrosarcoma
malignant
Heberden’s nodes (DIP)
osteophytes
obese 60 y/o
osteoarthritis
Bouchard’s nodes also seen (PIP)
Ulnar deviation of fingers
Baker’s cyst
MCP/PIP involvement
stiffness improves with use
Rheumatoid arthritis Type III HS rxn anti-IgG assc with HLA-DR4 tx with TNF-alpha inhibitors
Dry eyes
dry mouth
joint pain
female 52 y/o
Sjoegren's syndrome xerophthalmia/xerostomia/arthritis parotid enlargement increased B cell lymphoma Abs to riobnucleoprotein Ags assc with RA
Needle shaped/(-) birefringent yellow crystals
swollen joints
pain with EtOH/food
more common in men
Gout
monosodium urate crystals
can be from Lesch-Nyhan syndrome/Von Gierke’s diease
painful MTP joint of great toe
Rhomboid crystals with weak (+) birefringence
knee joint pain
66 y/o
Pseudogout
calcium pyrophosphate crystals
blue color
Bamboo spine
stiff spine
aortic regurg
uveitis
Ankylosing spondylitits
chronic inflammatory diease of spine/SI joints
assc with HLA-B27
Conjunctivitis
urethritis
arthritis
Reactive arthritis/Reiter’s syndrome
post GI/chlamydia infection
Progressive symmetric prox muscle weakness
shoulder involvement
(+) ANA and anti-Jo-1
muscle atrophy
Polymyositis
CD8 T cell inflammation
Dermatomyositis (CD4 T cells) if malar rash/Gottron’s papules/heliotrope rash present
Muscle weakness, worsens with use
ptosis
Myasthenia gravis
Abs to ACh receptor
assc with thymoma
Muscle weakness, imrpvoes with use
proximal muslces
Lambert-Eaton syndrome
Abs to presynaptic Ca2+ channels
assc with small cell lung cancer
45 y/o women
no wrinkles
anti-Scl-70 Ab (+)
Scleroderma
sclerosis of organs
rapid progression
Calcinosis Raynaud's dysphagia sclerodactyly telangiectasia
CREST syndrome
esophageal dysmotility (dysphagia)
anti-Centromere Ab
MOA of bisphosphonates
bind hydroxyapatite in bone
inhibit osteoclast activity
47 y/o male
growth on tibia
glistening mass in medullary cavity
chondrosarcoma
malignant
11 y/o male
onion skin appearance of bone
diaphysis of femur
Ewing’s sarcoma
highly aggressive
assc with t(11,22) translocation
16 y/o male
growth at the knee
metaphysis of femur
pt has Paget’s disease
Osteosarcoma (osteogenic sarcoma)
Sunburst pattern on x-ray
malignant tumor
Codman’s triangle
25 y/o
growth at epiphyseal end of femur
double bubble/soap bubble on x-ray
Giant cell tumor (osteoclastoma)
spindle shaped cells with multinculeated giant cells
benign tumor
Osteitis fibrosa cystica
overproduction of PTH
brown tumors of hyperparathyroidism
Increased ALP
Mosaic bone pattern
chalk stick fractures
Paget’s disease of bone
hyperactivity of osteoblasts & osteoclasts
increased AV shunts and osteogenic sarcoma
Bowing bones
increased alkaline phosphatase
Osteomalacia/rickets (in children)
Vit D deficiency
defective mineralization
hyperactivity of osteoblasts
Thick, dense bones
multiple fractures
pancytopenia
facial n. palsy
Osteopetrosis/marble stone disease
defective osteoclasts
mutation of carbonic anhydrase II
bone marrow space filled (pancytopenia)
Tx for senile osteoporosis
weight lifting/Ca2+/Vit D
Estrogen/Calcitonin/bisphosphonates/pulsatile PTH
AD
short limbs/lg head
assc with older father
Achondroplasia
FGFR3 mutation constitutive expression
Estrogen’s role in bone formation
inhibits apoptosis of osteoblasts
induces apoptosis of osteoclasts
Origin of osteoclasts
macrophages/monocytes
Membranous ossification
facial/calvarium bones
woven bones formed directly
Endochondral ossification
in axial/appendicular skeleton/base of skull bones
cartilage made first by chondrocytes
later replaced by lamellar bone (via osteoblasts/osteoclasts)
Fast twitch muscles
white color
anaerobic glycolysis
decreased myoglobin/mitochondria
Skeletal m. contraction sequence
depolarization moves down T tubule
voltage sensitive dihydropyridine receptor/ryanodine receptor releases SER Ca2+
Ca2+ binds troponin C/myosin free to bind
mysosin releases ADP/power stroke
Which band of sarcomere shortens with contraction?
H and I bands
A band remains constant
Trouble walking up stairs
can’t jump
Inf gluteal (L5-S2) post hip dislocation
Loss of thigh abduction
Sup gluteal (L4-S1) post hip dislocation
Foot drop
Common peroneal (L4-S3) knee trauma
Loss of thigh flexion/leg extension
femoral (L2-4) n.
pelivc fracture
Loss of thigh adduction
obturator (L2-4) n.
ant hip dislocation
Hand muscles innv by ulnar n.
Opponens digiti minimi
abductor digiti minimi
flexor digiti minimi
Hand muscles innv by median n.
Opponens pollicis
abductor pollicis brevis
flexor pollicis brevis
Winged scapula
lymphedema on ipsilateral side
Long thoracic n. (C5-C7)
loss of serratus ant fxn
Ape hand lesion
proximal median nerve lesion
loss of opponens pollicis m. fxn
Pope’s blessing lesion
proximal median n. lesion
loss of lat finger flexion/thumb opposition
Lesion with median claw
dislocated lunate/carpal tunnel
cannot extend 2nd/3rd digits
distal median n.
