Ulnar Nerve Exam

Look

 

Splints

 

Extend elbow to side

- medial wounds

- extension

 

Flex elbow to side

- flexion range

 

Flex elbow to front

- olecranon wound

 

Extend elbow to front

- anterior wounds

- carrying angle

- forearm wasting

 

Palm up

- clawing

- hypothenar eminence

- scars

 

Ulna Nerve Laceration

 

Thumb up

- thenar eminence

 

Ulna nerve wasting

 

Palm down

- interossei / adductor pollicis wasting

 

Adductor Pollicis WastingUlna nerve wasting

 

Palms together

- claw

- hypothenar eminence

 

Feel

 

Sensation

 

1.  LF & RF

 

2.  Dorsal branch ulna nerve

- branches above wrist

- runs under FCU

- dorsum of hand, ulna side

- dorsum LF and half RF to P2

 

3.  Palmar cutaneous branch

- above wrist

- hypothenar eminence

 

3.  Medial forearm (MCNF / T1)

- above ulna

 

Move

 

Above elbow

 

1.  FCU (C7)

- patient flexes wrist, palpate

 

2.  FDP (C8) 

- patient makes fist & resists extension of LF

 

Below wrist

 

1.  AbDM

- LF together

- first branch deep nerve

 

2.   1st Dorsal Interossei

- push both IF together

- last branch deep nerve

 

3.  Adductor Pollicis

- Froment's sign

- hold paper between thumb and IF
- positive if patient uses FPL to grip

 

Ulna Nerve Positive Froment's Sign

 

4.  Card sign

- between index and middle finger

- PAD

- palmar interossei adducting

 

5.  Lateral 2 lumbricals

- unable to pad to pad  LF / RF

- lumbricals extend DIPJ

- patient can only tip to tip

 

Special Tests

 

Tinel's - Cubital tunnel, Guyon's

 

Ulna nerve subluxation / tenderness

 

DDx

 

T1

- thumb APB weak / wasted

 

C8

- EDC / Wrist extension weak

 

TOS

- sensory loss above wrist

- Addson sign

 

Compression Syndromes

 

1.  Medial Intermuscular septum 

- arcade of Struthers (fascial band)

- septum

- hypertrophied medial head triceps

 

2.  Medial epicondyle

- tardy ulna nerve palsy, previous fracture

 

3.  Epicondylar groove

- intrinsic (SOL, synovitis, rheumatoid nodule

 

4.  Cubital Tunnel 

- tendinous arch of FCU

 

5.  Exit FCU

 

6.  Guyon's canal

- FDP OK

- palmar & dorsal br spared

- all small hand m's affected

 

7.  Deep motor branch only

- can be compressed against pisiform & hamate 

- with using mallet, vibrating tools

- sensation normal