Neural pattern in the human pollical distal phalanx.

摘要

A morphological study of the neural pattern in the human ungual region of the pollical distal phalanx was carried out on eight male cadavers. The dissections showed a palmar neural arrangement consisting of four designated ungual nerves, two proximal and two distal, for each of the ulnar and radial palmar digital nerves at the lateral sides of the thumb. This neural configuration was associated with the compartmentalization of its ungual pulp, the difference between the type of sensory receptors within the ungual pulp, the overlapping of the tactile composition at the thumb tip, seen clinically after laceration of one of the palmar digital nerves, and the sensory supply to the nail bed in the dorsal portion of the thumb. The proximal ungual pulp compartment had a single proximal medial ungual nerve, which did not appear, as far as visually possible, to overlap at the midline of the proximal ungual pulp. In contrast, the distal ungual pulp compartment was supplied by a medial and a lateral ungual nerve,both of which did appear to overlap to their contralateral sides in the thumb tip. A single proximal dorsal sensory nerve branched dorsally from each of ulnar and radial palmar digital nerves at the level of the proximal ungual pulp to supply the nail bed on the dorsum of the thumb.