final Flashcards
4 causes of peripheral nerve lesions
1: Compression
2. Trauma
3.systemic disorders
4. Systemic edematous conditions
First Degree classification
compression of a nerve causing local conduction block
Recovery to area occurs as damage is repaired
good progonosis
Neuropraxia
Second degree classification
Prolonged severe compression
degeneration of axon distal to injury
Regnereration can occur, good prognosis
* if lesion is too close to cell body = no regeneration
Aconotmesis
3rd degree classification
severing of the nerve trunk
surgery is type of repair
Neurotmesis
Regeneration of a nerve takes how long?
1-2mm a day
what direction does a nerve grow
Proximal to distal
Edema is present with complete lesion:
present initally, remain until fibers regenerate. the more fibres affected the worse the edema will be
Edema present with partial:
less the nwith complete, muscle function assists with lymphatic return
Altered tissue health with complete and Partial
complete: loss of autonomic function affects hair skin nails, tissue fragile, *loss of piloerection loss of swelling
Partial: increase piloerector over area of denervation
Motor function with complete and partial
Complete: Muscle flaccid
Partial: Muscle weakness, diminished deep tendon reflex
Holding pattern with complete and partial:
Complete: Sciatic nerve lesion = foot drop, drop wrist drop with radial nerve
Partial: finger drop rather than wrist
Contractures with complete and partial:
Complete: Contractures in atagonist mm
Partial: less severe then complete
Pain with Complete and Partial:
Complete: may not be interpreted as painful
Partial: an area of hyperesthesia (increased sensitivity) and dysesthesia ( abnormal sense of touch)
Permanent Lesion symptoms
Edema
holding pattern
scar tissue
Pain-more with partial permenant lesions
compensatory changes
several months before function returns if any
Compression syndromes eg: TOS, Carper tunnel, periformis syndrome
Neuropraxia
Causes of compression
External force ie: Crutches, backpack straps, splints
internal force: Hypertonic mm, trigger points, posture imbalances, saturday night palsy, pregnancy
Symptoms of compression
Pain tingling numbness weakness
the longer the disruption, the longer the recovery time*
Radial Nerve pathway
C5-T1
Radial nerve muscles innervated
Triceps
Aconeus
Brachioradialis
Extgensor carpi radialis longus and brevis
SUPINATOR
Extensor digitorum
Ex Carpi ulnaris
ex digiti minimi
Extenso Pollicis longus and brevis
extensor indicis
Ulnar nerve Pathway
C8-T1
under pec minor
Guyons canal is compression site for ulnar
M
Muscles innervated by ulnar nerve
Plexor carpi ulnaris
flexor digitorum profundus(medial half)
Adductor Pollicis *
Causes of ulnar lesions:
Fractures-Medial condyle
Dislocations
Post surgery complications
pathlogy -leprosy
prolonged compression
repetive action
direct trauma
Symptoms of ulnar nerve lesion
Claw hand
Fromonts sign positive
Median nerve Pathway
M c8-t1 L C5-c7
Between heads of pronator teres