Download Radial nerve injury

We have 3 principal nerves of the upper limb (UL)
Ulnar nerve
Median nerve
Radial nerve
C7,8,T1
Medial cord
C5678T1
Medial and lateral cord
C5-T1
Posterior cord
Motor supply
 Forearm
Motor supply
 Forearm
Motor supply
 Triceps , brachialis
(small part),
brachioradialis.
 Extensors of the
forearm; by the
posterior interosseus
nerve
- ED
- EDM
- ECU
- ABPL
- EPL
- EPB
- EIN

Ulnar ½ of the
FDP,FCU
Intrinsic hand
muscles
All intrinsic muscles
of the hand except 4
muscles; LOAF are
supplied by the
median nerve.


Flexors of the
forearm; pronator
teres, FCR, palmaris
longus, FDS.
Anterior interosseus
nerve supplies FPL
and ½ of the FDP.
Intrinsic hand
muscles LOAF;
- Lateral 2 lumbricals
- Opponens pollicis
- Abductor pollicis brevis
- Flexor pollicis brevis
Sensory supply
Medial one and ½ fingers
and medial third of the palm
of the hand
Sensory supply
 Lateral 3 and ½
fingers and lateral
2/3 of the palm of
the hand.
 The palmar
cutaneous branch
supplies the lateral
palmar skin
Partial claw hand




Finger spreading test
Card test
Froment’s test
Sensory distribution
Ape hand



Abductor pollicis
brevis test
Tinel’s test
Phalen’s test
Sensory supply
 Radial 1 ½ fingers
dorsally by the
superficial branch.
 Skin on the back of the
forearm by the
posterior cutaneous
nerve of the forearm.
Wrist drop

Wrist extension test
As before;
1. Greet the patient and introduce your self
2. Expose both hands, forearms and elbows
3. Don’t shake hand with the patient
Map;
Inspect;
Sensory
Skin
Soft tissue
Bone & Joint
Motor
Don’t forget:
 I would like to examine the neck i.e. cervical rib
 I would like to examine other peripheral nerves.
Four quick tests of the motor and sensory innervation of the hand
Autonomous Motor innervation;
Median nerve……abduct the thumb
Radial nerve……extend the wrist at the level of the MCP joint
Ulnar nerve……abduct the fingers
Autonomous sensory innervation;
Median nerve……index finger
Radial nerve……..lateral aspect of the base of the thumb
Ulnar nerve……….little finger
Ulnar nerve injury
Inspect;




Scar of injury
Claw hand ( ring & little finger)
Wasting of the hypothenar muscles
Guttering of the dorsum of the hand obvious on the 1st web space.
Sensory;

Loss of sensation on the little finger (middle & distal phalanges)
N.B; compare both sides
Motor;
 Palmar interossei
 Dorsal interossei
 Adductor polices
card test
finger spreading test
froment’s test
N.B; compare both sides
How to identify level of injury?
1. Scar site
2. Flexion of both PIP.J and DIP.J indicate lower lesion but if PIP.J only
indicate proximal lesion
(Ulnar Paradox)
3. Wasted medial forearm
proximal lesion
4. Inability to flex ring & little finger
proximal lesion
5. Loss of sensations at the ulnar side of the dorsum of the hand
proximal lesion.
DDX;
Partial claw hand
1.
2.
3.
4.
5.
Ulnar nerve injury
Volkmann’s ischemic contracture
Dupuytren’s contracture
Post-burn skin contracture
Congenital contracture of the PIP.J of the little
finger.
Complete claw hand
1.
2.
3.
4.
5.
Combined ulnar & median nerve injury
Volkmann’s ischemic contracture
Advanced rheumatoid arthritis
Lesions of the medial cord of the B.P
Lesions of the spinal cord e.g. poliomyelitis
Radial nerve injury (spiral groove)
Saturday night paralysis
Inspect;


Wrist drop & finger drop ( ask the patient to keep his hands out in front of
him, palms downwards)
No wasting of the hand muscles.
Sensory;


Loss of sensation over the 1st dorsal interosseus space ( between the thumb
and the index finger)
Loss of sensation over the dorsal aspect of the forearm.
Motor;

Loss of extension at the level of the MCP.J and wrist.
N.B:



Triceps weakness only in higher lesion (axilla)
Posterior interosseus lesion
only finger drop & no sensory loss
IPJ extension is preserved in radial n. injury as lumbricals & interossei are
supplied by the ulnar and median ns.
Median nerve injury
Inspect;

Thenar muscle wasting
Sensory;

Loss of sensation over the distal phalanges of the index and middle fingers
Motor;

Test of abductor polices brevis & Opponens polices
Tests;


Tinel’s test
Phalen’s test
Tapping
Maximum flexion for one minute will induce pain
Qs;
 What is the finger that receives sensory fibers from all 3 nerves
of the hand?
Middle finger
 How to assess the motor power of the 3 nerves of the hand?
“ OK ” sign




What are the causes of ulnar nerve lesions?
How do you treat ulnar nerve palsies?
What are the causes of radial n. lesions?
What are the causes of carpal tunnel syndrome?