Brachial Plexus Injury Flashcards
(45 cards)
What are two different MOI for brachial plexus can be injured at birth?
- traction
2. Compression
How does traction cause BPI?
uneven decent of one shoulder vs other shoulder becomes stuck @ mother’s pubic symphysis anterior, sacrum posteriorly
How does compression cause BPI?
combination of abnormally shaped uterus and position of fetus
Where can a BP lesion be in SC?
- at level of nerve rootlet
- at anterior and posterior rootlets
- at distal to where the rootlets form mixed nerve roots
What is etiology of BPI?
difficult vaginal delivery, congenital abnormalities
What are risk factors for BPI in regards to the infant?
- high birth weight over 3500 g
2. sedated infant during delivery from meds given to mom leads to low tone
What are risk factors for BPI in regards to the mother?
maternal diabetes, prolonged maternal labor, breech or shoulder dystocia
What are three types of BPI lesions?
- neurotmesis
- Axonotmesis
- neurapraxia
What is neurotmesis?
rupture or avulsion of BPI, axon, myelin and connective tissue avulsed, no regeneration possible, can be partial or complete
What can result as sequelae from neurotmesis?
fibrous mass formation, hemorrhage into subarachnoid space (diagnostic indicator for avulsion)
What is axonotmesis?
disruption of axons with intact neural sheeth, regeneration is possible
What is neurapraxia?
temporary nerve conduction block, intact axons good prognosis
What are signs and symptoms of a BPI?
spinal cord level c5-T1, motor and sensory innervation, decreased spontaneous movement, absent moro reflex, absent grasp, Horner’s syndrome
What is Horner’s syndrome?
if sympathetic chain is involved- mitosis (contracted pupils), ptosis and anhidrosis (lack of face sweating)
What is a big indicator of a positive outcome in recovery for BPI?
are the neural sheaths still intact if they are than neurons can still reconnect
What is regeneration rate of axons?
1 mm/day, upper arm 4-6 mo., lower arm 7-9 mo., continues 2-4 years
How are BPI injuries classified?
based on spinal root level, severity of injury
Narakas usually used
What are examples of Narakas classification?
Upper Erb’s c5-6- 80% recovery rate
Total palsy with Horner’s syndrome c5-t1- worst outcome
What is Erb’s palsy?
most common type of BPI affecting upper plexus roots c5-c6 resulting in paralysis of shoulder. scap muscles, elbow forearms, wrist and fingers
What muscles of shoulder are affected by Erb’s palsy?
deltoid, RC, SA, rhomboids, LS
What muscles of elbow are affected by Erb’s palsy?
biceps, brachioradialias, brachialis, supinators
What muscles of hand are affected by Erb’s palsy?
wrist extensors and finger extensors
What are other possible impairments of Erb’s palsy?
sensation loss- lateral aspect of upper arm, can also have elbow extension if C7, “waiter’s tip resting position”
What is most serious type of BPI?
Erb- Klumpke- also second most common ,global plexus palsy C5-T1, ms weakness
