Upper Extremity Neuropathies Flashcards
What is the Ape hand deformity?
Compression of median nerve leading to thumb and thenar atrophy
What is the sensory distribution of the median nerve?
Pollex, 2nd, 3rd, and half of 4th digit
The median nerve supplies all forearm flexors except __________ and the _______ part of __________
Flexor carpi ulnaris
Ulnar part of flexor digitorum profundus
(Supplied by ulnar nerve)
What are the autonomous zones of the median nerve?
Area supplied only by the median nerve: Tips of the 2nd and 3rd digit
The median nerve supplies all thenar muscles except ______________ and the __________ head of ____________
Adductor pollicis
Flexor pollicis brevis
Both supplied by ulnar nerve
Which muscle is used in EMG testing for the median nerve?
Abductor pollicis brevis
Name 6 causes of median nerve compression in the axilla
- Improper use of crutches
- Missile injuries/stab wounds
- Improper venipuncture
- Sleep palsies
- Humeral head fracture
- Shoulder dislocation
Name the 7 points of entrapment of the median nerve
- Axilla
- Next to humerus
- Elbow
- Bicipital aponeurosis
- Pronator teres
- Sublimis bridge
- Carpal tunnel
What 3 structures in the elbow can cause median nerve entrapment?
- Struther’s ligament (off medial epicondyle into brachial fascia)
- Brachialis muscle (MC post-operative)
- Bicipital aponeurosis
What is another name for entrapment of the median nerve in the bicipital aponeurosis?
Lacertus fibrosis
What is the sublimis bridge?
Fibrotendinous arcade from origin of FDS muscle
What functional test should be done to check for median nerve compression at the elbow?
Pincer grip (lost with. Median nerve compression)
The median nerve travels through the carpal tunnel with (#) flexor tendons
9:
FDP (4)
FDS (4)
FPL (1)
The median nerve divides into motor and sensory branches (before/after) the carpal tunner
After (except palmar cutaneous sensory branch)
What is the MC median nerve compression site?
Carpal tunnel
What 6 conditions can cause reduced size of the carpal tunnel, increasing the risk for CTS?
RA Exostosis/osteophytes Ganglia Lipomas/hemangiomas Gouty tophi Abnormal muscles and tendons (palmaris longus, lumbricals)
Which 3 conditions increase susceptibility to nerve compression?
Polyneuropathy (presdisposes to demyelination)
Diabetic neuropathy
Long term renal dialysis