Median Nerve Flashcards
Median nerve arises from which cord of brachial plexus?
Medial cord
Lateral cord
Median nerve arises from which roots?
All 5(C5- T1)
C5
C6
C7
C8
T1
Median nerve gives rise to which sensory branches?
1.Palmar cutaneous branch
(Lateral part of palm)
2.Digital cutaneous branch
(3 lateral fingers)
Thumb
Index
Middle
Initially Medial nerve is _______ to brachial artery?
Initially—–Lateral
Then becomes more —-medial
Median nerve enters the elbow at?
Cubital fossa
|
Then enters to anterior compartment of forearm
Within the forearm, the median nerve travels between which two muscles?
- Flexor dogitorum superficialis
- Flexor digitorum profundus
The two branches of median nerve in forearm?
- Anterior interosseous nerve (proximally)
- Palmar cutaneous nerve
(Distally)
The anterior interosseous branch of median nerve supplies? Name the muscles
Flexor muscles of anterior compartment of forearm:
1.Flexor pollicis longus
2.Pronator quadratus
3.Flexor digitorum profundus (lateral half)
Palmar cutaneous nerve of median nerve passes ________ to flexor retinaculum?
Over
Palmar cutaneous nerve innervates?
Skin of lateral palm
Median nerve enters the hand and and divides into which branches?
- Recurrent branch
- Palmar digital branches
Recurrent branch innervates?
Thenar muscles
(Abductor pollicis brevis
Flexor pollicis brevis
Opponens pollicis)
What is CTS?
Carpal Tunnel syndrome
Median nerve gets compressed in Carpal tunnel eliciting pain over the coarse of median nerve
Tests for CTS?
1.Tinel’s sign
Tapping the nerve in carpal tunnel to elicit pain in median nerve distribution
2.Phalen’s manoeuvre
Phalen’s maneuver is positive whenflexing the wrist to 90 degrees for 1 minute elicits symptoms in the median nerve distribution.
Motor function of median nerve?
Innervates:
1.Majority muscles of anterior compartment of forearm
2. Intrinsic hand muscles
Innervation by median nerve to anterior forearm is to which muscles?
Superficial layer
- Pronator Teres
- Flexor carpi radialis
- Palmaris longus
Intermediate
1.Flexor digitorum superficialis
Forms anterior interosseous nerve supplies deep flexors
Palmar cutaneous branch innervates?
Lateral 2 lumbricals
Of index
And middle finger
Which *
flex the MCP
Extend the IP
What causes lesion of median nerve?
Damage to elbow
In lesion of median nerve what fracture occurs?
Supracondylar fracture of humerus
What are the affected motor functions in lesion of median nerve?
1.Paralysis of flexors (except flexor carpi ulnaris and flexor digitorum profundus)
& pronators
2. Prevention of flexion of thumb (thenar muscles) (also flexor pollicis longus + brevis are affected)
3. Lateral 2 lumbricals;
Middle and index
What are characteristic signs of lesion of median nerve?
- Atrophy of thenar muscles
-
Hand of benediction
When try to make a fist, only little and ring fingera are flexed
Median nerve passes ________ to flexor retinaculum?
Behind
Is flexor pollicis longus affected by CTS?
No, as median nerve innervates it before passing through carpal tunnel
Median nerve lies deep to ______ in the cubital fossa?
Bicipital aponeurosis
Median nerve leaves cubital fossa by passing between?
2 heads of pronator teres
At the wrist, the median nerve emerges from ______ border of flexor digitorum superficialis?
Lateral
At wrist, median nerve lies ______ the tendon of palmaris longus?
Behind
