Nerve Injury (Proximal Ulnar Nerve)

Overview


Plain-Language Overview

Nerve Injury (Proximal Ulnar Nerve) affects the ulnar nerve, which is a major nerve running from the neck down the arm to the hand. This condition involves damage to the nerve near the elbow or upper arm, leading to problems with hand movement and sensation. People with this injury may experience numbness, tingling, or weakness in the ring and little fingers. The ulnar nerve controls many small muscles in the hand, so injury can cause difficulty with fine motor tasks like gripping or typing. This condition impacts the nervous system and can significantly affect daily activities that require hand coordination.

Clinical Definition

Nerve Injury (Proximal Ulnar Nerve) is defined as damage to the ulnar nerve at or above the level of the elbow, often caused by trauma, compression, or entrapment. The injury disrupts axonal conduction and nerve signaling, leading to motor weakness and sensory deficits in the ulnar nerve distribution. Common mechanisms include fractures of the medial epicondyle, prolonged elbow flexion, or direct blunt trauma. Clinically, this injury manifests as claw hand deformity, loss of sensation in the medial one and a half fingers, and impaired intrinsic hand muscle function. It is significant because it can cause permanent disability if untreated, affecting hand dexterity and grip strength. Electrophysiological studies often reveal slowed conduction velocity or conduction block at the site of injury.

Clinical Presentation


Diagnostic Workup


Pathophysiology


Treatments


Prevention


Outcome & Complications


Differential Diagnoses


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