periferal nerve Entrapment neuropathiies Flashcards
What 2 nerves from the median nerve needs to be looked out for?
- Palmar cutaneous branch.
- Recurrent motor branch to the thumb.
Between what two tendons is the transpalmar incision done for carpal tunnel syndrome?
Palmaris longus to the ulnar side and flexor carpi radialis to the radial side.
What vessel is running in a bow under the incision line in a carpal tunnel incision?
The superficial palmar arch.
what is the recurrent motor branch called and from what mothernerve does it stem?
“The million dollar nerve” law suit.
From the median nerve
Elecrtrodiagnostic criteria for the ulnar neuropathy at the elbow?
Not all criteria need to be present and a needle EMG is not needed.
* Absolute MN conduction velocity under 50m/s from elbow to above elbow.
* Drop of conduction velocity with more than 10m/s in the underarm compared to above elbow.
* Amplitude of compound motor action potential normally decreases by distance, but a drop of more than 20% is abnormal.
mer sägs men detta är core.
What can be done in ulnar entrapment?
Nerve decompression with or without transposition. Mostly without.
Where is the ski incision in a ulnar decompression?
around and below the medial condyle.
what are the results of ulnar decompression?
60% excellent
25% fair
15% poor (nothing or worsening)
What is a pancoast tumor?
most often due to bronchogenic ca.
Situated close to the brachial plexus
* Atrophy of hand muscles
* Horner syndrome
Radiating pain.
How can preganglionic injuries be differentiated from postganglionic?
-proximal or distal to the dorsal root ganglion-
Pre ganglionic:
* horner syndrome
* Wing scapula - long thoracic nerve injury –serratus anterior
* Rhomboid paralysis - dorsal scapular nerve
* PSeudomeningocele on MRI associated to root avulsion and associated neuropathic pain.
EMG - cannot be done until 3 weeks after injury to get a any findings.
What does EMG find to suggest preganglionic injury?
- Denervation potentials in paraspinal muscles due to loss of neural input. The posterior ramus of of the spinal nerve originates just distal to the dorsal root ganglion.
- Normal sensory nerve action potential - SNAP- preganglionic injuries leave the dorsal ganglion sensory bodies and the distal axon intact. A normal SNAP can therefore be recorded proximally EVEN IN AN ANESTHETIC REGION!
What is a SNAP?
sensory nerve action potential ( from nerve body in the dorsal ganglion to the distal axon in the limb.
Which is the most common lack of function due to a birth brachial plexus injury?
Upper plexus injuries. C5 and C6 and sometimes C7 too.
What is a surgical option for birth upper plexus injuries (C5-7)
Nerve transfer if no antigravity in deltoid, bicep or tricep at 3 mo age.
What is the definition of a thoracic outlet syndrome?
compression of the area between the apex of the lung, the 1st rib and the clavicle.
