REVIEW DSA Compression Neuropathy Flashcards
define neuropathy
functional or pathological changes in PNS
define compression neuropathy
process where nerve becomes entrapped as it passes through narrow tunnel or passage
what are the biomechanical causes of neuropathy? (4)
space occupying lesions: herniated discs, cysts
degenerative: foraminal stenosis
post-traumatic: fracture, hematoma, compression
mechanical: muscle spasm, pinching
list the systemic causes of neuropathy (3)
pregnancy
hypothyroidism
diabetes
describe the 3 layers of a nerve
epineurium: fascicles, blood vessels, connective tissue
perineurium: covers fascicles / groups of axons
endoneurium: covers myelin sheath over axons
what are the pathological changes associated with neuropathy (4)
epineurium thickening
myelin thinning disortion
microtubule closure
axonal degeneration
List the 5 degrees of compression nerve injuries according to Sutherland’s Classification
1st: neuropraxia: focal damage of myelin; connective tissue sheath intact
2nd: axonotmesis: axon injury; myelin sheath intact
3rd: disruption of axon & endoneurium
4th: disruption of axon, endoneurium & perinerium
5th: disruption of axon, endoneurium, perineurium, epineurium
list the 3 common sites for radial nerve entrapment
high on humerus
radial tunnel
at the wrist
describe symptoms and treatment of high humeral radial nerve entrapment
Sx: wrist drop, weak elbow flex, possible tricep reflex diminshed, pain / numbness
Tx: restored fxn 4-5months
describe the symptoms for radial tunnel radial nerve entrapment
Sx: pain & tenderness 5cm distal to lateral epicondyle
wrist drop or pain w/ resisted supination
describe symptoms of radial nerve entrapment at the wrist
pinching of nerve during forearm pronation, sensation changes over posterolateral hand
pain with resisted forearm pronation and finger cramping indicates which nerve damage?
median n.
anterior interosseous syndrome is an injury in what nerve?
what is the testing?
median n.
have pt. make “OK” sign
Pt. has parasthesia of their 4th and 5th digits, medial elbow pain with decreased intrinsic m. strength, sx are reproduced with elbow flexion and wrist extension, what sign do you expect to be positive? how do you treat?
ulnar n. entrapment (cubital tunnel syndrome)
+ Tinel’s sign, + Froment’s sign
tx: padded elbow sleeve to limit terminal elbow flexion and provide cushioning
what causes carpal tunnel syndrome?
medial n. entrapment as it passes under flexor retinaculum
What sx do you see with carpal tunnel syndrome?
diagnosis?
nighttime numbness of lateral 3.5 digits, tingling, wrist pain, thenar atrophy
dx: EMG
what is thoracic outlet syndrome?
symptoms?
compression of the brachial plexus &/or subclavian vessels
Stx: weakness, paresthesia of medial arm / forearm / hand
what are the sites of compression in thoracic outlet syndrome? (3)
scalene triangle
costoclavicular passage
pec minor attachment at coracoid process
what tests are done for thoracic outlet syndrome?
what is the cause of meralgia paresthetica?
compression of lateral femoral cutaneous n. under inguinal ligament at inguinal canal
what are causes of meralgia paresthetica? (4)
intense athletics
obesity
tight belt / clothing / seat belt (MVA)
anatomic anomaly
what are the symptoms of meralgia paresthetica? (3)
numbness or burning pain anterolateral thigh
hyperesthesia (skin sensitivity) + trophic skin changes
(+) Tinnel sign 1cm inferomedial to ASIS
where does compression in the common fibular nerve (L4-S2) occur?
as nerve winds around fibular neck and enters fibular tunnel
what are causes of common fibular nerve compression? (4)
bedridden
time spent in squatting “strawberry picker”
ankle sprain
lithotomy childbirthing position
what is tarsal tunnel syndrome?
compression of posterior tibial nerve in tarsal tunnel behind medial malleolus
list causes of tarsal tunnel syndrome (4)
50% idiopathic
lesion (cyst, lipoma etc.)
trauma
autoimmune / congenital / diabetes
symptoms of tarsal tunnel syndrome?
treatment?
plantar surface pain
vague burning / tingling/ numbness
tx: MFR, HVLA
define anterior tarsal tunnel syndrome
symptoms?
compression of deep fibular nerve at inferior extensor retinaculum
Stx: dorsomedial foot pain, worst at rest, weakness of extensor digitorum brevis
etiology of anterior tarsal tunnel syndrome? (4)
trauma
talonavicular dysfunction
prolonged plantar flexion
compression from shoes
