The document provides information about ulnar nerve injury, including its course through the upper limb, branches and sensory/motor supply. Causes of injury include compression at sites like the elbow (cubital tunnel syndrome) and wrist (Guyon's canal syndrome). Signs and symptoms involve sensory loss and weakness of hand muscles. Clinical tests assess functions like pinching. Investigations include EMG, nerve conduction studies and imaging. Claw hand deformity can occur with severe ulnar nerve injury.
3. INTRODUCTION
1. Ulnar nerve is the largest branch of Medial cord of brachial plexus.
2. Its root value is Ventral rami of C7,C8 & T1 spinal segments.
3. It is named as “Ulnar” because it runs along the Medial/Ulnar side of the
upper limb.
4. It is also known as the “Musicians Nerve” as it supplies the Intrinsic
muscles of the hand which are responsible for fine movements.
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5. NERVE COURSE
In the arm:-
• It lies on the medial side of axillary artery.
• It runs downwards with the brachial artery in the proximal part.
• At the middle of Humerus it pierces the medial intermuscular septum to
lie on the back & descends on the back of medial epicondyle,where it can
be palpated.
• Palpation causes tingling sensations.
6. In the forearm:-
• It enters the forearm between two heads of Flexor carpi ulnaris (FCU) &
descends along the medial side of forearm.
• Here it lies anterior to the Flexor digitorum profundus (FDP) along with the
ulnar vessels.
7. At the wrist:-
• It passes in front of Flexor retinaculum just lateral to the pisiform bone.
• On entering the palm, the nerve then divides into Superficial & Deep
branches supplying the muscles of hand.
12. CAUSES
General causes:-
1. Metabolic causes.
2. Collagen diseases.
3. Malignancies.
4. Endogenous or Exogenous toxins.
5. Thermal, Chemical or Mechanical trauma.
13. Local causes :- Based on different levels
In the Axilla:-
• Crutch pressure.
• Aneurysm of axillary vessels.
In the Arm:-
• Fracture shaft of Humerus.
• Gunshot & penetrating injuries.
14. At the elbow:-
• Fracture of medial epicondyle of Humerus.
• Repeated occupational strains.
• Dislocation of elbow.
• Compression by osteophytes in RA & OA.
• Cubitus valgus deformity.
In the forearm:-
• Compartment Syndrome.
• Volkmann’s Ischaemic Contracture (VIC).
• Radius-Ulna fracture.
• Tight plaster (POP)cast.
15. At the Wrist:-
• Osteoarthritis.
• Compression in Guyon’s Canal.
• Fracture Hook of Hamate.
• Glass cut injuries.
In the Hand:-
• Blunt trauma.
• Occupational people operating high-speed drills in rock mining.
• Cyclists by Overpressure of hand on the handle.
• Associated ulnar artery aneurysm.
16. ENTRAPMENT SITES
The ulnar nerve could be entrapped at any one of the
following sites during its anatomical course:-
1. Arcade of Struther i.e. Near the medial intermuscular septum.
2. Medial supracondylar region of Humerus.
3. Between two heads of Flexor carpi ulnaris (FCU).
4. Guyon’s canal.
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18. SIGNS & SYMPTOMS
Sensory loss:-
• Skin overlying the Hypothenar eminence.
• Medial 1½ finger upto the nail beds.
Motor loss:-
• Flexor carpi ulnaris (FCU).
• Medial ½ of Flexor digitorum profundus (FDP).
• The Hypothenar muscles (HTM).
• Medial 2 lumbricals.
• Adductor pollicis (AP).
• The Interossei muscles.
19. Functional disability:-
• The patient will lack lumbrical grip.
• Power grip is more affected due to lack of the elevationof Hypothenar
eminence i.e. Inability of the fingers to wrap around the object.
• Pinch power reduces.
• Spherical grip is lacking due to absence of lateralization of fingers.
• Lateral pinch becomes inefficient due to paralyzed Adductor pollicis.
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24. Trick movements:-
• Due to paralysis of lumbricals, EXTENSION of IP joint will be possible
only when the MCP joint is supported in flexion.
• Due to paralysis of dorsal interossei, the patient will try to ABDUCT the
finger using Extensor digitorum which also causes extension of the fingers.
• ADDUCTION of the finger can be brought about by direct substitution
using the long flexors of the hand.
• ULNAR DEVIATION can be brought about by Extensor carpi ulnaris
(ECU).
25. • In place of Adductor pollicis, the patient will use Flexor pollicis longus
(FPL) known as the Froment’s sign.
• Co-contraction of Flexor pollicis longus (FPL) & Extensor pollicis
longus (EPL) nullify their action at the DIP joint thereby pulling the
thumb into ADDUCTION.
• The 1st sign of recovery at wrist is INCREASED ABDUCTION attitude of
LITTLE FINGER because the Abductor digiti minimi (ADM) is the 1ST
MUSCLE to recover.
26. CLINICAL TESTS
A) Froment’s sign:-
• The patient is asked to hold a book
between the thumb & other fingers.
• In ulnar nerve injury, the 1st two
muscles are paralyzed & now the
patient has to depend on Flexor pollicis
longus (FPL) which flexes the thumb
prominently.
27. B) Card test:-
Inability to hold a card or paper between the fingers due to loss of
adduction by the palmer interossei.
28. C) Egawa test:-
• With the palm placed flat on the
table, the patient is asked to
move the middle finger
sideways.
• This is a test for the dorsal
interossei of middle finger.
29. D) Pen test:-
The patient is unable to touch the pen due to the loss of Abductor pollicis
brevis (APB).
30. ENTRAPMENT SYNDROMES
1. It is classified based on the location of entrapment.
2. Due to vulnerability to injury because of COMPRESSION or
ENTRAPMENT, it is so-called a “Pinched nerve”.
3. The most common site is at the ELBOW which is followed by the
WRIST.
31. A) CUBITAL TUNNEL SYNDROME
1. The impingement or compression of the ulnar nerve into the Cubital
tunnel is known as Cubital tunnel syndrome.
2. The tunnel is formed by the Medial epicondyle of the Humerus, the
Olecranon process of Ulna & the Tendinous arch joining the Humeral
& Ulnar heads of the Flexor carpi ulnaris (FCU).
32. Causes:-
1. Sleeping with the arm folded behind neck, elbows bent.
2. Pressing the elbows upon the arms of chair while typing.
3. Resting the elbow on the arm-rest of the vehicle.
4. Intense exercising and strain involving the elbow.
5. Bench pressing.
33. Clinical features:-
1. Numbness in small & ulnar fourth finger.
2. If untreated, the numbness may progress to Hand weakness.
3. “Ulnar claw hand” is the characteristic feature at rest.There is curling
up of small & ring fingers & occurs in later stages & is a sign of
severe neuropathy.
4. Atrophy occurs in advanced cases.
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35. B) GUYON’S CANAL SYNDROME
1. The impingement or compression of the ulnar nerve into the Guyon’s
canal is known as Guyon’s canal syndrome.
2. It is also known as Ulnar tunnel syndrome.
3. It is a semi-rigid longitudinal canal in the wrist that allows the passage
of ulnar artery & ulnar nerve into the hand.
36. Anatomy:-
• ROOF:- It is made up of Superficial palmer carpal ligament.
• FLOOR:- It is made up of Deeper flexor retinaculum & Hypothenar
muscles.
• MEDIAL BOUNDARY:- It is bounded by the Pisiform & Pisohamate
ligament more proximally.
• LATERAL BOUNDARY:- It is bounded by the Hook of Hamate more
distally.
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38. • EXTENSION:- It is 4cm long which
begins at the Transverse carpal ligament
proximally and ends at the Aponeurotic
arch of the Hypothenar muscles.
39. Clinical features:-
1. Motors symptoms & Claw hand are more pronounced.
2. “Ulnar paradox” is the characteristic feature.
3. The sensation at the back of hand is PRESERVED.
40. ULNAR PARADOX
1. The higher the lesionof the Median & Ulnar nerve injury, the less
prominent is the deformity & vice-versa.
2. This is because in higher lesions the long finger flexors are paralyzed.
3. The loss of finger flexion makes the deformity look less obvious.
41. C) CLAW HAND DEFORMITY
Definition:-
Its is a deformity with HYPEREXTENSION of the MCP joints &
FLEXION of the IP joints of fingers.
Types & causes:-
1. True claw hand when there is Median + Ulnar nerve involvement.
2. Ulnar claw hand or Claw-like hand whether is only Ulnar nerve injury.
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44. Clinical features:-
1. It is a classical deformity.
2. Loss of sensation in ulnar nerve distribution area.
3. Wasting of hypothenar muscles.
4. Intrinsic muscles of hand leads to Hollowing of Intermetacarpal spaces
on the dorsum of the hand.
5. The clinical features depends upon the level of lesion.
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49. INVESTIGATIONS
The investigations used in diagnosis of peripheral nerve injuries
are as follows:-
1. Plain radiograph.
2. Electromyography (EMG).
3. Strength-Duration (S-D) curve.
4. Nerve conduction (NCV) studies.
5. Tinel sign.
50. REFERENCES
1. Physiotherapy in Neuro conditions - Glady Samuel Raj.
2. Essential Orthopaedics for Physiotherapists - John Ebnezer.
3. Essential Orthopaedics - J.Maheshwari.
4. Human Anatomy Vol.1 - B.D.Chaurasia.