ICL 4.4: UE Plexopathies

Question 1

what is plexopathy?

Answer 1

plexopathy is a disorder affecting a network of nerves, blood vessels, or lymph vessels

typically occurs distal to roots and proximal to peripheral nerves (but not always)

the region of nerves it affects are at the brachial (upper) or lumbosacral (lower) plexus

usually diagnosed with history, PE, imaging, electrodiagnostics

symptoms include pain, loss of motor control, and sensory deficits

Question 2

what can cause plexopathy?

Answer 2

1. trauma

traction, transection, obstetrical injuries, compression, hemorrhage

2. cancer

tumor, radiation

3. idiopathic

neuralgic amyotrophy

Question 3

what innervates the FDP of the 2nd and 3rd fingers?

Answer 3

anterior interosseous nerve

Question 4

what innervates the FDP of the 3rd and 4th fingers?

Answer 4

ulnar nerve

Question 5

which nerve is related to wrist drop?

Answer 5

radial neuropathy

to double check that the neuropathy isn’t effecting nerves higher up on the posterior cord you should check somewhere innervated by the axillary nerve like the deltoid

Question 6

what part of the brachial plexus are you at when you’re at the clavicle?

Answer 6

the divisions!

the divisions are sitting at the level of the clavicle

Question 7

what is a traction plexopathy?

Answer 7

it’s a pulling type of injury to the nerves of the brachial plexus; most common type of nerve injury

usually supraclavicular

may be due to birth trauma*, sports, MVA/MCA

rhomboid and serratus anterior may help distinguish root from plexus injury (EDX)

many have associated pain syndromes

treatments can include meds* and surgery

Question 8

what is Erb’s palsy?

Answer 8

typically upper trunk plexus traction injury involving C5-C6 nerve roots

usually due to obstetrical injury but may also be sports related like during a tackle that pulls the neck away (Burner-Stinger syndrome)

“waiter’s tip” = C5-C6 innervate proximal muscles of the shoulder

treat with rehab and splints in abduction, external rotation, flexion, supination, and wrist extension positions

Question 9

which sport has the highest incidence for traction type injuries aka stingers?

Answer 9

football in the US but in the world it’s rugby

Question 10

what parts of the body are weakened with Erb’s Palsy?

Answer 10

the kids will be ____ due to weakness of _____:

1. adducted: deltoid, supraspinatus
2. internally rotated: teres minor, infraspinatus
3. extended: biceps, brachioradialis
4. pronated: supinator, brachioradialis
5. wrist flexion: ECRL, ECRB

Question 11

what is Klumpke’s palsy?

Answer 11

traction injury to inferior trunk plexus = C8-T1 nerve roots

usually due to hyper-abduction injury; usually obstetrical but could also be due to MVA or falls

pts. present with distal weakness like loss of hand intrinsics which could cause claw hand deformity

affects anterior interosseous nerve and ulnar nerve innervated forearm muscles, distal radial innervated muscles but shoulder girdle is preserved

Question 12

how do you treat Klumpke’s palsy?

Answer 12

rehabilitation for incomplete lesions and surgical exploration w/ nerve root avulsion

Question 13

what is a neoplastic plexopathy?

Answer 13

may involve brachial or lumbosacral plexus –> usually lower trunk of brachial plexus and painful***

may be associated with neurofibromas, schwanommas, sarcomas, neuromas

primary tumors are rare but secondary tumor from lung or breast can cause injury to plexus

may see Horner’s syndrome

Question 14

what is Horner’s syndrome?

Answer 14

associated with neoplastic plexopathy

1. mitosis = constriction of pupils
2. ptosis = drooping eyelids
3. anhidrosis = no sweating

this is often because of Pankos tumors which have a predilection for your lower trunk of brachial plexus

Question 15

which cancers are associated with a neoplastic plexopathy?

Answer 15

1. lung
2. breast
3. larynx
4. colon
5. esophagus
6. thyroid

Question 16

what is radiation plexopathy?

Answer 16

it’s a progressive demyelination, connective tissue fibrosis, loss of vascular structures of the nerves

usually effects the superior trunk which then could continue down to the lateral cord

painless

most commonly due to high frequency of radiation use and can occur anywhere from 1-30 years post exposure –> most common with breast cancer treatment

might have lack of sensation in median nerve distribution which is associated with hand intrinsic weakness

Question 17

what is idiopathic brachial plexopathy also known as?

Answer 17

1. neuralgic amyotrophy

2. neuralgic amyotrophy

Question 18

what is idiopathic brachial plexopathy?

Answer 18

totally unknown

can be idiopathic, inflammatory, immune-related, or worked out too much

usually there’s a trigger like URI or overdoing it while working out

male > female

Question 19

what is the clinical presentation of an idiopathic brachial plexopathy?

Answer 19

some kind of trigger followed by sudden onset of severe pain at the shoulder girdle specifically

pain might resolve in hours or up to weeks all on its own without treatment; doctors just help with symptoms and controlling pain and not losing strength in effected muscles

symptoms are all over, it doesn’t just effect one specific nerve which is a hallmark of this –> most patients have bilateral involvement

Question 20

which nerves are most commonly affected by idiopathic brachial plexopathy?

Answer 20

1. Long Thoracic (Serratus anterior)
   2/3 may be bilateral
2. Suprascapular (supraspinatus, infrapinatus)
3. Axillary (Deltoid)
4. AIN (FPL-flexor pollicus longus, FDP – flexor digitorum profundus)

however IBP is known for effecting all over but these are the nerves that are most likely effected

Question 21

how do you treat idiopathic brachial plexopathy?

Answer 21

steroids if it’s inflamed

start rehab ASAP; goal is to prevent contractures

recovery is usually quick but can be up to 2-3 years on it’s own

Question 22

what is thoracic outlet syndrome?

Answer 22

over diagnosed…

there are 2 types: vascular or neurogenic

1. vascular = involves subclavian artery, subclavian vein, or axillary vein that could be compressing on plexus
2. neurogenic = may be due to compression by 1st cervical rib (costoclvaciular syndrome), scalenes (anterior and middle), pectoralis minor (pec minor syndrome), or a fibrous band on the plexus

it’s dynamic so symptoms aren’t always present

Question 23

what part of the body is more commonly effected in thoracic outlet syndrome?

Answer 23

ulnar distribution is more common than median distribution

median motor is effected and ulnar sensory is effected and the reason is because of T1:

your lateral cord and medial cord contribute to form median nerve so a majority of your median motor is coming from T1

while your ulnar sensory is effected because your medial cord branches into the medial antebrachial nerve

Question 24

what’s the clinical presentation of vascular thoracic outlet syndrome?

Answer 24

1. Arterial involvement

Limb Ischemia

Necrosis

Vague pain

Fatigue

Decreased color and temp

2. Venous involvement

Bluish

Swollen

Achy

Question 25

what’s the clinical presentation of neurogenic thoracic outlet syndrome?

Answer 25

pain and numbness along medial aspect of forearm and hand –> increase with overhead activity

discomfort in neck, clavicle and axilla

hand muscle wasting: Median thenar > Ulnar intrinsics

Adson’s test and Roos test

Question 26

what is Adson’s test?

Answer 26

used for thoracic outlet syndrome

passively abduct, extend and externally rotate patients arm while monitoring radial pulse

have pt rotate head toward the arm

decrease or loss of pulse may be related to compression of subclavian artery

this would be considered a vascular TOS

Question 27

what is the Roos test?

Answer 27

used for neurogenic thoracic outlet syndrome

patient has both arms in 90o abduction-external rotation with shoulders and elbows in the frontal plane of the chest

patient then opens and closes hands slowly over a 3-min period

normal = forearm fatigue & minimal distress

abnormal = gradual increase in pain @ neck and shoulder progressing down the arm

1. paresthesia in forearm & fingers
2. venous compression with cyanosis & swelling
3. drop arms d/t marked distress

Question 28

what is the treatment for thoracic outlet syndrome?

Answer 28

1. rehabilitation treatment

focus on ROM
exercises

stretching of muscles – anterior/middle scalenes, pec minor, trapezius and levator scapulae

strengthening of scapular stabilizers – upper/middle trap and rhomboids

2. surgical treatment = first rib or fibrous band resection

Question 29

what is nerve root avulsion?

Answer 29

severe injury at the nerve root level where the root gets ripped off from the spinal cord – traction injury that disrupts protective connective tissue support

usually traumatic like an accident

C8 and T1 are usually effected because they’re less protection

will present as absent sensation or muscle contraction from muscle innervated by the roots involved = “flail shoulder”

Question 30

how do you diagnose nerve root avulsion?

Answer 30

MRI

helps you differentiate between just a nerve root stretch vs. total avulsion

Question 31

what is backpack palsy?

Answer 31

due to carrying heavy backpack over the shoulder

associated with lateral neck deviation

can get variable plexus injury; may be predicated to upper plexus (think about where backpack straps are)

**painless motor weakness – more just weakness in shoulder girdle and elbow flexors

you will see sensory disturbances – lateral shoulder/arm, radial aspect of forearm/hand

weight of carried load at symptom onset related to severity of muscle strength loss –> treatment is taking the weight off

Question 32

what are the common superior trunk plexopathies?

Answer 32

1. Erb’s (traction)
2. Burner/stinger syndrome (traction)
3. radiation
4. anesthesia (poor positioning during surgery)

Question 33

what are the common inferior trunk plexopathies?

Answer 33

1. Klumpke’s
2. neoplastic
3. neurogenic thoracic outlet syndrome
4. open heart surgery – if they have extensive retraction of the ribs you can cause your first rib to fracture or cause compression which would effect the ulnar and median nerve

Question 34

which brachial plexopathy is painless?

Answer 34

radiation palsy

Question 35

which nerve will not be affected by a C5 nerve root injury?

A. dorsal sapular

B. suprascapular

C. musculocutaneous

D. median nerve

E. ulnar nerve

Answer 35

E. ulnar nerve