Ulnar nerve palsy

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

Damage Locations
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