Clinical testing of ulnar nerve palsied

1. Clinical Testing- Ulnar nerve
Dr.Roopchand.PS
Senior Resident Academics
Department of Neurology

2. Introduction:
• A mixed nerve.
• Main branch of the medial cord of the brachial
plexus.
• Root value is C7 C8 T1
• Main supply to the small muscles of hand.
• Also called musicians nerve.

4. • ARM
– crosses the axilla beneath the pectoralis
minor
– medial to the brachial artery in upper arm
– distal arm it enters a groove between the
medial humeral epicondyle and the
olecranon process.
– The cubital tunnel: Aponeurosis between
the olecranon and medial epicondyle forms
the roof of an osseous fibrous canal the
floor of which is formed by the medial
ligament of the elbow joint.

5. • ELBOW:
– passes between the humeral and ulnar heads of
the flexor carpi ulnaris to rest on the flexor
digitorum profundus.
– Immediately distal to the elbow joint
• Br to flexor carpi ulnaris
• Br to flexor digitorum profundus III and IV
• FOREARM:
– descends beneath the flexor carpi ulnaris
– palmar cutaneous branch at distal forearm
– supplies the skin over the hypothenar eminence.

6. – then gives of dorsal cutaneous branch.
– supplies the dorsal ulnar aspect of the hand and the
dorsal aspect of the 5th finger and half of the 4th finger.
• WRIST:
– enters the wrist lateral to the tendon of the flexor carpi
ulnaris muscle.
– gives of the superficial terminal branch
– skin of the distal part of the ulnar aspect of the palm
and the palmar aspect of the fifth and half of the 4th
finger.
– passes between the pisiform carpal bone medially and
the hook of the hamate carpal bone laterally: canal of
Guyon

7. • Passes as deep muscular branch supplies:
– Palmaris brevis (C8–T1).
– Abductor digiti minimi (C8–Tl)
– Opponens digiti minimi (C8–T1)
– Flexor digiti minimi (C8–T1)
– Lumbricals III and IV (C8–T1)
– Interosseous muscles (C8–Tl)
– Adductor pollicis (C8–T1)
– Deep head of the flexor pollicis brevis (C8–Tl)

9. NERVE LESIONS:
• Lesions above the Elbow:
– May present as triad neuropathy.
– sleeping with the arm hanging over a sharp edge
or the head of a sleeping partner compressing the
nerve against the humerus, crutches or
tourniquets, arteriovenous fistulas in dialysis
patients, aneurysms, hematomas, nerve tumors,
and other masses.
– Supracondylar fractures of the humerus
– Ulnar entrapment neuropathy in the midarm:
compression by the medial intermuscular septum

10. • “claw-hand”
• Paresis or paralysis of the ulnar flexion
• Impaired extension at the interphalangeal joints.
• Impaired adduction and abduction of the second
to 5th fingers.
• Impaired abduction and opposition of the fifth
finger.
• Froment’s thumb sign : adductor pollicis
weakness- proximal phalanx of the thumb is
extended and the distal phalanx is flexed when a
paper grasped between thumb and index finger is
pulled.
• Sensory abnormalities.

11. • Martin-Gruber anastomosis: a median-ulnar
communication.
– the crossing of fibers from the median to the ulnar
nerve usually occurs 3 to 10 cm distal to the
medial humeral epicondyle.
– median fibers ultimately innervate the intrinsic
hand muscles.
– The overall incidence of Martin-Gruber
anastomoses is approximately 17%.
– Four types exsists.

12. • Cubital Tunnel Syndrome: lesion at the elbow
– most commonly compressed at the elbow in the cubital
tunnel.
– Narrowing of tunnel during flexion, thickening of
aponeurotic arch, ganglion cyst, mass lesions, fibrous
bands, bony spurs…
– More in patients with renal disease undergoing dialysis
and during general anesthesia.
– Tardy ulnar nerve palsy: ulnar nerve palsy occurring long
after original injury.
– A reliable sign of ulnar entrapment by the flexor carpi
ulnaris muscle is the ulnar extension manoeuvre, in which
increased paresthesias in the fourth and fifth digits follow
3 minutes of elbow and wrist flexion in ulnar deviation.

13. Cubital tunnel synd Vs tardy ulnar
palsy:
• No evidence of joint deformity or prior trauma
• Frequent occurrence of bilateral symptoms and
signs of ulnar neuropathy
• A taut, palpably enlarged nerve in the ulnar
groove
• Electrophysiologic (electromyographic)
localization to the cubital tunnel
• Operative findings of a swollen, taut, hyperemic
nerve, distally limited by the proximal border of
the aponeurosis joining the two heads of the
flexor carpi ulnaris muscle.

14. • Ulnar neuropathy at the elbow often spares
the flexor carpi ulnaris
• involvement of flexor carpi ulnaris more often
correlates with the severity of the neuropathy.
• Involvement related to the internal
topography of the nerve, severity of
compression, level of compression.
• preferentially compress the nerve fascicle to
distal hand muscles

15. • Lesions in the Forearm:
– Causes: hypertrophied flexor carpi ulnaris muscle,
fibrous and fibrovascular bands, hematomas, and
handcuffs.
– flexor carpi ulnaris and the flexor digitorum
profundus iand II muscles are often spared

16. Lesions at the Wrist and in the Hand:
• Flexor carpi ulnaris and the flexor digitorum
profundus III and IV are spared.
• Compression of the nerve as it enters the
hand.
• Compression of the proximal part of the
terminal motor branch(with in Guyons canal)
• Distal compression of the terminal motor br.

17. • Common causes:
– Ganglion, occupational neuropathy, laceration, ulnar
artery aneurysm, carpal bone fracture.
• Palmaris brevis spasm syndrome: following the
prolonged use of a computer mouse and
keyboard.
• Lesions of the Dorsal Cutaneous Branch of the
Ulnar Nerve
– Handcuff palsy, Pricer palsy
• Pseudoulnar Nerve Palsy: isolated hand weakness
apparently in an ulnar distribution that is due to
• contralateral cerebral infarction in the white
matter of the angular gyrus of the inferior
parietal lobe