Ulnar nerve palsy

The most common cause of ulnar nerve palsy is its damage. It occurs in several typical places.

Damage Locations


The course of the nerve.

Nervus ulnaris passes through several straits.
 * 1) In the place of the septum intermusculare brachii mediale, where it enters from the sulcus bicipitalis medialis.
 * 2) Behind the medial epicondyle of the humerus it passes in the sulcus nervi ulnaris.
 * 3) In canalis cubitalis – canal between the olecranon and the beginning of the m. flexor carpi ulnaris.
 * 4) In the ulnar tunnel (Guyon canal on the hand).
 * Injuries to the ulnar nerve most often occur with a cut on the volar side of the wrist, where the nerve is located superficially.



Image of polio

 * Inability to flex II.-V. of the finger in the metacarpophalangeal joints (mm. interossei).
 * Inability to adduct and abduct II.–V. finger (mm. interossei).
 * Inability to flex in the distal interphalangeal joint IV. and V. finger (m. flexor digitorum profundus).
 * Severe adduction of the thumb - a novel symptom.
 * Claw-like hand – metacarpophalangeal joints extended (predominance of extensors), interphalangeal joints in flexion (predominance of flexors), thumb abducted.
 * Sensitivity disorders in the innervation area.

Causes of paralysis

 * 1) Syndrome cubital tunnel - chronic microtraumatization during exertion in the elbow.
 * 2) Compression in Guyon's canal - mainly motor disability, hypothenar is usually spared; atrophy of the 1st interosseus dominates.
 * 3) Chronic compressive syndromes - rheumatological diseases, arthritic disfigurements, external compression when leaning on a mat (eg: glass grinders).
 * 4) Axillary lesion' - very rare (eg: compression with high crutches).''
 * 5) Trauma - fractures in the elbow area (eg: dislocations and displaced fractures), cuts in the wrist area.
 * 6) Soft tissue tumors - lipoma, fibroma.

Related Articles

 * Ulnar nerve
 * Examination of the ulnar nerve
 * Peripheral nerve involvement syndromes
 * Canalis cubitalis
 * Humerus
 * Guyon Channel
 * Cubital landscape
 * Mm. interossei manus
 * Upper Extremity Bones