3. Ulnar Nerve
Also called MUSICIAN’s Nerve - Fine Movements of the Hand
• Major Terminal Branches Of medical cord of Brachial Plexus C8-T1
4. Muscles supplied
• In Forearm:
Flexor digitorum profundus(medial part) and Flexor carpi ulnaris
• In wrist:
• Superficial terminating branch:
Palmaris Brevis
• Deep terminating branch:
Abductor digiti minimi,Flexor digiti minimi,Opponens digiti minimus,All interossei and 3rd and 4th lumbricals
5. Injuries Gives raise to
CLAW HAND DEFORMITY
• It is a deformity with hyper extension of the MCP joints and flexion of the
fingers(loss of flexion at MCP and extension at IP joints
• When patient is asked to extend the fingers the patient will not be able to
extend the interphalangeal joints of fourth and fifth finger.
6. Causes
• Crutch Pressure
• Fracture of shaft of humerus
• Gunshot and penetrating injures
• Dislocation of elbow
• Cubitis valgus deformity
• Compartment syndrome
• Tight POP cast
7. Clinical test
• Froment's sign: When the patient attempts to pinch the paper with the thumb
and side of index finger the thumb will flex at the interphalangeal joint if the
adductor of the thumb is paralyzed.
• Card test : Inability to hold a card or paper in between fingers due to loss of
adduction by the palmar interossei
• Pen test : Unable to touch the pen due to the loss of action of abductor pollicis
brevis
8. Non-surgical Management
1)Anti – inflammatory drugs, ibuprofen, ( to reduce swelling around the nerve ).
2)Steroid (cortisone) injections around the ulnar nerve are not generally used
because there is a risk of damage to the nerve.
3)Exercises ( prevents arm and wrist from stiffness ).
9. Surgical Management
If the nerve is very compressed; or if there is muscle wasting
Around the elbow and the wrist or both More commonly, the nerve is moved from
its place behind the elbow to a new place in front of the elbow. This is called an
anterior transposition of the ulnar nerve.
The nerve can be moved :
1)under the skin and fat (subcutaneous transposition),
2)within the muscle (intermuscular transposition)
3)under the muscle (submuscular transposition).
10. Prevention
1)Avoid frequent use of the arm with the elbow bent
2)If you use a computer frequently, make sure that your chair is not too low. Do
not rest the elbow on the armrest.
3)Avoid putting pressure on the inside of the arm (do not drive with the arm
resting on the open window ).
4)Keep the elbow straight at night when you are sleeping (done by wrapping a
towel around the straight elbow, wearing an elbow pad backwards, or using a
special brace )
12. Motor supply
Forearm:
• Flexor carpi radialis, pronator teris, palmaris longus, lateral half of flexor digitorum profundus, flexor digitorum
superficialis, flexor pollicis longus, pronator quadratus
• All anterior compartment of forearm except :
Flexor carpi Ulnaris and medial half of flexor digitorum profundus.
Hand:
• Abductor pollicis brevis.
• Flexor pollicis brevis.
• Opponens pollicis.
• Lumbricals 1, 2.
• All thenar muscles except adductor pollicis.
13. Sensory supply
• Lateral 2/3rd of palm
• Lateral 3 ½ of fingers
• Distal phalanx of lateral 3 ½ fingers
14. Course and branches
• Mixed nerve (contain motor & sensory fibers).
• Root value: C 5, 6, 7, 8 & T 1
• Runs in the median plane of the forearm , so its called median nerve Median nerve is formed by lateral
root from lateral cord and medial root from medial cord of brachial plexus.
• Median nerve runs lateral side of axillary artery In arm
• Median nerve continues to run on the lareral side of brachial artery till the middle of arm , where it
crosses infront of the artery and passes anterrior to the elbow joint into forearm.
• Enters to the forearm b/w two heads of pronator teres
• Muscular braches supply muscles of thenar eminence ( abductor pollicis brevis , opponens pollicis and
flexor pollicis brevis )Finally divides into 4 to 5 palmar digital branches supplying lateral three and half
digit and their nail beds
• Also , motor branches are given to the first and second lumbrical muscles
15. Injury to median nerve
Median nerve is most commonly injured near the wrist or high up in the fore arm
Injury in the distal third of the forearm
Cuts infront of wrist or by carpal dislocation
There will be sparing of the forearm muscles , but the muscles of the hand will
be paralysed
Thenar eminence is wasted and thumb abduction and opposition are weak.
Sensation is lost over the radial three and half digits and trophic changes may
seen
16. High median nerve palsy
Injury proximal to the elbow
Generally due to forearm fractures or elbow dislocation.
Stabs and gunshot wounds may damage the nerve at any level
This will cause paralysis of all the muscles supplied by the median nerve in the
forearm and hand
17. Clinical test
• OK Sign is test for anterior interosseous nerve injury for flexor digitorm
profundus and flexor pollicis longus to check for paralysis due to entrapment
or compression injury.
• Benediction test test for flexor digitorm profundus / flexor digitorm
superficialis-When patient tries to make a fist they are unable to flex the index
and middle finger due to loss of lateral lumbrical action leads to hand of
benediction
• Ape- thumb sign –Cannot move the thumb away from the rest of the hand due
to paralysis of thenar muscle
• Positive pen test / test for adductor pollicis brevis
18. • Egawas test :with the palm placed flat on the table patient is asked to move
the middle finger sideways to test for dorsal interossei of middle finger
• Oschner clasping test: When patient is asked to clasp the hands Index finger
of the affected side fails to flex remains as a pointing index.
19. Non-surgical treatment:
Avoid activities that produce pain and stress
-RICE method -—To reduce stress
-NSAIDS ---– reduce pain and inflammation
-Immobilisation,Bracing ----- promote recovery
-Steroids ----- reduce inflammation
