1. NERVE INJURIES OF UPPER LIMB
By: Dr. Mujahid Khan

2. Brachial Plexus Injuries (upper lesions)
These are caused by the excessive displacement of the head to the opposite side
Depression of the shoulder on the same side
This causes excessive traction of C5 and C6 roots of the plexus

4. Muscles to be Paralyzed
Supraspinatus (Abductor of shoulder)
Infraspinatus (lateral rotator of shoulder)
Biceps brachii (flexor of elbow)
Coracobrachialis (flexor of shoulder)
Deltoid (Abductor of shoulder)
Teres minor (lateral rotator of shoulder)

5. Erb-Duchenne Palsy The limb hangs limply by the side likened
to a waiter or porter
hinting for a tip
There will be a loss of
sensation down the
lateral side of arm

6. Brachial Plexus Injuries (Lower lesions)
Are usually a traction injuries caused by excessive abduction of the arm
The first thoracic nerve is usually torn
The hand has a clawed appearance caused by hyperextension of metacarpophalangeal joints & flexion of interphalangeal joints

8. Brachial Plexus Injuries (Lower lesions)
Loss of sensation will occur along the medial side of the arm
Lower lesions can also be produced by a presence of a cervical rib or malignant metastases from the lungs in the lower deep cervical lymph nodes

9. Axillary Sheath
A brachial plexus nerve block can be obtained by injecting a local anesthetic
The position of the sheath can be verified by feeling the pulsations of the 3rd part of the axillary artery

10. Injuries of Long Thoracic Nerve
Can be injured by blows to or pressure on the posterior triangle of the neck
Serratus anterior is paralyzed
The patient feels difficulty in raising the arm
The vertebral border & inferior angle of scapula protrude posteriorly
Known as winged scapula

12. Injuries of Axillary Nerve
Can be injured by the pressure of a badly adjusted crutch pressing upward into the armpit
It is vulnerable during the downward displacement of the humeral head in shoulder dislocations or fractures of the surgical neck of the humerus
Paralysis of deltoid and teres minor muscles results

13. Axillary Nerve
Loss of skin sensation over the lower half of the deltoid muscle
Paralyzed deltoid wastes rapidly
Underlying greater tuberosity can be palpated
Abduction of the shoulder is impaired
Paralysis of teres minor is not recognized clinically

14. Injuries of Radial Nerve
Can be injured by:
Pressure of badly fitting crutches
Drunkard falling asleep with one arm over the back of a chair
Fractures or dislocation of the proximal end of the humerus

15. Findings in Radial N. Injury
Triceps, anconeus and long extensors of the wrist are paralyzed
Unable to extend the elbow joint, wrist joint and fingers
Wrist drop or flexion of wrist occurs
Unable to flex the fingers firmly for gripping
Brachioradialis & supinator are paralyzed

17. Sensory Findings
Little loss of skin sensation over posterior surface of lower part of the arm
Sensory loss on the lateral part of dorsum of the hand
Sensory loss on the dorsal surface of the roots of the lateral 3 & ½ fingers

18. In the Spiral Groove
Radial nerve can be injured in the spiral groove at the time of fracture of shaft of the humerus
Wrist drop occurs
Sensory loss on the dorsal surface of the roots of the lateral 3 & ½ fingers

19. Deep Branch of Radial Nerve
Can be damaged in the fracture of the proximal end of radius or during dislocation of the radial head
No wrist drop as extensor carpi radialis longus is undamaged
No sensory loss as this is a motor nerve

20. Injuries of Musculocutaneous Nerve
Rarely injured due to its protected position beneath the biceps brachii muscle
If injured high up in the arm, the biceps & coracobrachialis are paralyzed & brachialis is weakened
Sensory loss along the lateral side of the forearm occurs

21. Injuries of Median Nerve
Can be injured:
Occasionally in the elbow region in supracondylar fractures of the humerus
Commonly injured by stab wounds or broken glass just proximal to the flexor retinaculum
Here it lies between the tendons of flexor carpi radialis and flexor digitorum superficialis

22. Injury at Elbow (motor)
Pronator muscles of forearm, long flexor muscles of the wrist & fingers will be paralyzed
Forearm is kept in supine position
Wrist flexion is weak & accompanied by adduction
No flexion at interphalangeal joints of index & middle fingers

23. Injury at Elbow (motor)
When the patient tries to make a fist, the index & middle fingers tend to remain straight
Only ring & little fingers flex
Flexion in these fingers is weakened by the loss of the flexor digitorum superficialis

25. Injury at Elbow (motor)
Flexion of terminal phalanx of thumb is lost because of paralysis of flexor policis longus
The thumb is laterally rotated and adducted
Muscles of thenar eminence are paralyzed
The hand looks flattened and ape like

26. Injury at Elbow (sensory)
Skin sensation is lost on the palmar aspect of the lateral 3 & ½ fingers
Sensory loss occurs on the skin of the distal part of the dorsal surfaces of the lateral 3 & ½ fingers
Total area of anesthesia is less

27. Injury at Elbow (vasomotor changes)
The skin areas involved in sensory loss are warmer and drier than normal
Arteriolar dilatation and absence of sweating resulting from loss of sympathetic control

28. Injury at Elbow (Trophic changes)
In long standing cases:
Skin is dry and scaly
Nails crack easily
Atrophy of the pulp of the fingers

29. Injury at Wrist
Almost all the clinical findings are same as injury of the median nerve at elbow
In addition a delicate pincer like movement is not possible

30. Carpal Tunnel Syndrome
The carpal tunnel is formed by the concave anterior surface of carpal bones and closed by flexor retinaculum
Clinically, the syndrome consists of a burning pain or pins & needles along the distribution of the median nerve
Lateral 3 & ½ fingers are involved

31. Carpal Tunnel Syndrome
The exact cause is difficult to determine
Condition is relieved by decompressing the tunnel by making a longitudinal incision through the flexor retinaculum

32. Injury to the Ulnar Nerve (motor at elbow)
Flexor carpi ulnaris & medial half of flexor digitorum profundus are paralyzed
In a tightly clenched fist the tightening of the tendon of profundus is absent
Profundus tendon to the ring & little fingers will be functionless
Terminal phalanges of these fingers fail to flex properly

33. Injury to the Ulnar Nerve (motor at elbow)
Flexion of wrist joint will result in abduction due to paralysis of flexor carpi ulnaris
Small muscles of hand will be paralyzed except the muscles of thenar eminence and first 2 lumbricals
Adductor pollicis longus is paralyzed so the adduction of thumb is not possible

34. Injury to the Ulnar Nerve (motor at elbow)
Metacarpophalangeal joints become hyperextended due to the paralysis of lumbrical and interosseous muscles
Interphalangeal joints are flexed due to the same reason as mentioned above
Dorsum of hand will show hollowing due to the wasting of dorsal interosseous muscles

35. Injury to the Ulnar Nerve (sensory at elbow)
Loss of skin sensation of anterior & posterior surfaces of the medial 3rd of the hand and medial 1 & ½ fingers
The skin areas involved in sensory loss are warmer and drier than normal
Arteriolar dilatation and absence of sweating resulting from loss of sympathetic control

36. Injury to the Ulnar Nerve (motor at wrist)
Small muscles of the hand will be paralyzed
Claw hand is more obvious as flexor digitorum profundus is not paralyzed
Marked flexion of the terminal phalanges occur

38. Injury to the Ulnar Nerve (sensory at wrist)
The sensory loss is usually confined to the palmar surface of medial 3rd of the hand and the medial 1 & ½ finger
Trophic changes are same as that injuries of ulnar nerve at elbow
Unlike median nerve injuries, lesions of ulnar nerve leave a relatively efficient hand
Pincer like action is good