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Flashcards in Brachial Plexus Deck (32):
1

Most common traumatic brachial plexus injuries are:

supraclavicular injuries involving complete involvement of all roots (80%)

2

Speed of nerve regeneration is:

1mm per day.
Plexus recovery can take up to 3 years

3

Worst prognosis is with these injuries:

root avulsions (pre-ganglionic)
- not reparable

4

Best prognosis with these injuries

Infraclavicular plexus injuries
Upper plexus injuries (preserves hand function)

5

Signs of Pre-ganglionic Injury

-Horner's syndrome
- Medial scapular winging (Long thoracic n)
- flail arm
- normal histamine test
- elevated hemidiaphragm (phrenic)
- Rhomboid paralysis (dorsal scapular n)
-Cuff weakness (suprascapular n)
-Latissimus weakness
- EMG = no innervation to cervical paraspinals

6

Signs of post-ganglionic injury:

EMG with maintained innervation to cervical paraspinals
- abnormal histamine test... redness and wheal positive, NO FLARE

7

Most common brachial plexus obstetrical palsy:

Erb's
- C5, C6
- has best prognosis

8

Causes of a Klumpke Palsy

C7-8 root involvement
- hyperabduction injury
- cervical rib
- lung mets in lower deep cervical lymph nodes

9

Clinical features of a Klumpke:

- claw hand
- unopposed wrist extensors
- loss of hand intrinsics therefore IP flexion and MP hyperextension

10

Essential muscles to check in brachial plexopathy:

serratus anterior
- rhomboids (if functioning, then likely a post-ganglioinc)

11

Define: SNAPs

sensory nerve action potentials
- measured in NCS
- preserved in lesions proximal to the DRG. Therefore distinguishes between pre and post-ganglionic

12

Best clinical sign of nerve regeneration?

advancing Tinel sign

13

Indication for immediate surgical exploration?

sharp, penetrating trauma
- iatrogenic injuries
- open injuries
- progressive defects
- expanding hematoma or vascular injury

14

IS direct nerve repair possible for plexus injuries?

typically not as these are avulsion injuries

15

Nerve grafting plexus injuries:

- useful in traction injuries
- preferable to graft the upper and middle trunk

16

Neurotization for plexus injuries:

- transfer a working but non-essential motor nerve
- use extra-plexal source of axons such as CN XI, intercostal nerves, contra-lateral C7, CN XII

17

Oberlin Transfer:

ulnar nerve is used for upper trunk injury to gain biceps function

18

Horner's Syndrome

disruption of the sympathetic chain at C8 or T1 root level
- seen concomitantly with pre-ganglionic injuries at this level

19

Phrenic Nerve

C3,4,5

20

Neurotization to restore elbow flexion - what procedure?

ulnar nerve fascicle to biceps
AND
median nerve fascicle to the brachialis

21

Best surgical management of late-presenting plexopathies? (liek 2 years out...)

free muscle transfers
- nerve transfers unlikely to be sufficient due to loss of neuromuscular endplates at that time frame

22

Quadrilateral space syndrome

dominant shoulder in overhead throwing athlete
- axillary nerve compression
- atrophy of deltoid and teres minor

23

Risks for obstetrical brachial plexopathy

- LGA
- multiparous
- dystocia
- forceps
- breech
- prolonged labor

24

Upper extremity issues from obstetrical brachial plexopathy

- glenoid dysplasia, retroversion, humeral head flattening, posterior humeral head subluxation
- Elbow flexion contracture

25

Poor prognosis for recovery of obstetical plexopathy?

- lack of biceps function by 3 months
- preganglionic injuries

26

Narakas Classification

I: Erb's
II: Intermediate (C5-7)
III: total palsy without Horner's
IV: total palsy with Horner's

27

Elbow contracture of <40 degrees, treatment

serial extension splinting
casting if >40 deg
if recalcitrant to treatment, use surgery

28

How do you influence the natural history of glenoid dysplasia in obstetrical brachial plexopathy?

- address GH internal rotation contracture wth latissimus and teres major transfer
- ifdone at young age, significant remodeling potential exists
- relative contraindications include severe dysplasia such as glenoid convexity or absence, humeral head flattening

29

Waters Classification - significance

if Waters GH dysplasia types II or III, do latissimus/teres major transfer

if Waters IV or V, do humeral derotational osteotomy

30

When do you do reconstruction for post-ganglionic injuries?

at 3-9 months of life, using neuroma excision and sural nerve grafting

31

When do you reconstruct pre-ganglionic injuries?

at 3 months of life, using nerve transfers

32

What's the prognostic value of a Horner's syndrome in context of brachial plexopathy?

poor prognosis.
<10% will regain function (al-Qattan 2000, Waters 1999)