Musculoskeletal Flashcards
lunate vs scaphoid bone position
both carpal bones articulate with radius. lunate is immediately medial to scaphoid
thumb swings on which carpal bone?
trapezium
which bone is in center of wrist
capitate
lunate vs triquetrum bone
both carpal bones articulate with ulna, triquetrum bone is medial.
explain collagen synthesis
1) pre-pro alpha chain is translocated into RER. signaling protein is cleaved. now called pro alpha chain
2)hydroxylation of proline and lysine residues (vti C dependent)
3)glycosylation of selected lysin residues
4)assembly of procollagen triple helix (disulfide/hydrogen bonds)- problem here=osteogenesis imperfecta
Exocytosis
1)terminal propeptides cleaved by N- and C- procollagen peptidases. now called tropocollagen
2)collagen fibrils form spontaneously
3)fibrils are reinforced by covalent cross-linking (lysyl oxidase)- requires Cu2+. problems here=Ehler’s Danlos and Menkes
older pt with bone pain and increased phosphatase level-disease, cells involved, cancer risk
Paget’s disease-increased osteoclastc activations followed by increased activity of osteoblasts. increased risk for osteocarcoma
histo-haphazardly oriented, prominent cement lines, mosaic pattern of lamellar bone
chondrocytes
cells found in healthy cartilage
neonate with agenesis of sacrum, flaccid paralysis or legs, dorsiflexed contractures of feet and urinary incontinence. associated with what maternal disease?
caudal regression syndome, poorly controlled maternal diabetes
what abdominal muscle is needed to increase intra-abdominal/intrathoracic pressure during Valsalva maneuver?
rectus muscle.
how does valsalva maneuver help with paroxysmal supraventricular tachycardia? if this fails use what drug?
increases vagal tone to increase refractory period in AV node (slow conduction) andprevent reentrant circuit. if this fails use IV adenosine (increase K+ out of cells)
describe muscles and nerves involved in abduction of arm
0-10 supraspinatus (suprascapular nerve)
10-90 deltoids (axillary nerve)
>90 serratus anterior (long thoracic nerve)
note: paralysis of trapezius (spinal accessory) prevents upward rotation of scapula and inability to arm arm above the horizontal
-great auricular nerve and transverse cervical nerve, -greater occipital nerve
- branches of cervical plexus don’t innervate any muscles in the neck, provide cutaneous innervation only.
- dorsal ramus of 2nd cervical spinal nerve cutaneous innervation to skin in back of head, no muscles
terres minor-innervation and movement. muscles that help and oppose this action/nerve
axillary, adducts and laterally rotates
infraspinatus (suprascapular nerve) works with terres minor to laterally rotate the arm
and subscapularis (subscapularis nerve) opposes causing medial rotation
action of palatoglossus and palatopharyngeus/ nerve
buccinator/nerve
palatogossus-draw tongue and soft palate together (as occurs during swallowing)-CN10
palaopharyngeus-elevates pharynx (as occurs during swallowing)-CN10
buccinator-holds food against teeth while chewing-CN 7 (paralysis can lead to food and saliva b/t teeth and check)
muscles of mastication innervated by CN5
3Ms elevate jaw-masseter, temporalis, and medial pyerygoid
1 L lowers jaw-lateral ptyergoid
aneurysm of axillary artery within axilla may compress what part of the brachial plexus? why not trunk of brachial plexus?
any of the cord-they are all enclosed within the axillary sheath the first portion of the axillary artery. get their name b/c of their relation to the artery (lateral, medial and posterior).
lower trunk of the brachial plexus is above the clavicle. not in axillary sheath.
temporalis muscle in innervated by CN located where? not lower pons because?
CN V located in mid pons (along with 6). lower pons contains CN 7 (muscle of facial expression and stapedius muscle) and 8.
CNs in medulla
9,10,11,12
CNs in midbrain
3, 4
sarcomeres
I-band
H-band
A-band
I-contains actin
H-contains myosin
A-contains actin + myosin
explain organization of sarcomere
An Interesting Zoo Must Have Mammals (Actin in the I-band attache to the Z-line, Myosin in the H-band attaches to the M-line)
cafe au lait spots, polyostotic fibrosis dysplasia, precocious puberty, multiple endocrine disorders
McCune-albright (mosaic G protein signaling mutation)
examples of muscluskeletal diseases with
- no contraction in response to intracellular Ca2+
- uncoordinated contraction of myofibrils
- poor force generation on repeated stimulation
- impaired relaxation after a single contraction
- impaired energy production during contraction
- abnormality of troponin C or myosin
- T-tubule malformation
- myasthenia gravis
- myotonic dystrophy
- McArdle disease (glycogen storage disease type V)- defect in myophosphorylase
location of psoas vs erector spinae
- originates from anterior surface of transverse processes and lateal surface of corresponding vertebral bodies (T12-L5)
- large muscle group behind vertebral bodies-causes spine extension.