Upper Extremity Neurology Flashcards
Cervical plexus
The cervical plexus is a network of nerves from C1-C4. We are only responsible for knowing the supraclaviular N because they innervate the skin on the neck and shoulder.
There are 3.
Lateral supraclaviular N
Middle supraclaviular N
Medial supraclaviular N
What is the only cervical plexus nerve we have to know and why?
Supraclavicular nerve.
There are 3. It is important to know them because they innervate the skin on the neck and shoulder
What is Erb-Duchenne Palsy?
Erb-Duchenne Palsy occurs when there damage to the upper part of the brachial plexus.
This can occur when there dramatic increase in angle of your neck and shoulder, causing the damage to the anterior rami of your spinal roots at C5/C6.
A person with Erb Palsy syndrome will have WAITERS TIP ARM
- Medially Rotated
- Adducted
- Extended elbow
What is another name for Erb’s Duchenne Palsy?
Waiter’s Tip Arm
In Erb’s Palsy, where is the damage in the brachial plexus?
Upper brachial Plexus.
Usually C5/C6 anterior rami.
Klumpke Palsy is a upper/lower brachial plexus injury.
LOWER
What is the presentation for someone with Klumpke Palsy?
Claw hand- person claws their hand when trying to make a fist
What is the presentation for someone with Erbs Palsy?
Waiters Tip Arm
What is Klumpke Palsy?
Klumpke Palsy is going to be caused by damage to the lower brachial plexus, often caused by when you stretch your arm too far away from your trunk.
Ex. Falling off a tree and holding onto the branch.
What part of the brachial plex is damaged in Klumpke Palsy?
C8/T1.
John and Beth were having a contest: who can hang on the monkey bars for the longest.
If they do this for too long, what can happen?
Prolonged periods of working with your hands over your head can compress the [posterior, medial and lateral cords] of their brachial plexus.
Thus, John and Beth would have pain radiating down their arm, loss of sensation, tigling and weaking of hands
What happens if we injure the [musculocutaneous N]?
Our musculocutaneous n innervates our brachial flexors. It also has a branch coming off of it, called the [lateral antebrachial cutaneous nerve], which provides sentsation for our lateral forearm.
Damage to our MSC nerve would:
- Paralyze our brachial flexors
- Not allow us to flex our shoulder and elbow
- Cause numbness in our lateral forearm,
But we may still be able to flex and supinate because we have our (supinator and our brachioradialis m)
What happens if we injure our AXILLARY NERVE
- Deltoid atrophy.
- Paralysis of Teres Mijor and Deltoid Muscle
- Loss of sensation over the superior lateral part of our brachial arm.
- We cannot abduct 15-90 Degrees
What is in our triangular interval?
- Deep brachial artery
2. Radial Nerve
What is in our quadrangular space?
- Axillary nerve
2. Posterior circumflex humeral artery
Jimmy damaged his radial nerve. What will happen?
Radial nerve is responsible for extension.
He will develop wrist drop.
- Cannot extend the elbow.
- Cannot abduct or extend the thumb.
- Cannot extend the wrist
Damage to the Median Nerve at the wrist
The recurrent branch of the medial nerves innervates your thumb muscles and the 1st and second lumbrical.
Apes hand- Adducted thumb and thenar eminenance atrophy.
Damage to the Median Nerve at the elbow
Hands of benediction–> you could not flex your 2nd and 3rd digit + Apes hand (thumb is abducted and thenar muscle atrophy)
What nerves come off the upper trunk?
- N to the subclavius
2. Suprascapular N
What nerves come off the lateral cord?
- lateral pectoral n
What nerves come off the posterior cord?
- Upper subscapular n
- Lower subscapular n.
- thoracodorsal n
What nerves come off the medial cord?
- medial pectoral n
- medial brachial cutaneous n
- medial antebrachial cutaneous n
Injury to the radial nerve will cause
Depends where:
- Wrist drop (cannot extend the wrist)
- Elbow extension
- Thumb abduction and extension (because remember your pollicis muscles are extensors)
Other symptoms of Erb’s Palsy:
muscle atrophy of the affected arm.
Bird-winging of the affected scapula.
Klumpe Palsy presentation
Forearm is supinated
Fingers are flexed at DIPS and PIPS
Metacarpophalangeal joints are extended
Damage to the ulnar nerve can occur in one of four places
- posterior to the medial humeral epicondyle
- between the ulnar and humeral heads of the flexor carpi ulnaris
- wrist
- hand
Overall result of ulnar n damage?
- extensive loss of sensory and motor control in the hand
2. When a fist is made, appears as claws hand
t10-L1 damage
big leg braces
L2-L3
short leg braces (cane)
Thoracic spinal nerve
interCOSTObrachial nerve
comes off of the 2nd rib.
