The lunula is the crescent shaped whitish area of the nail bed of a fingernail or toenail.

To be specific it is located at the end of the nail that is closest to the skin of the finger but still lies under the nail.

It is white, half-moon-shaped, appears by week 14 of gestation, has unique histologic features. The lunula has a primary structural role in defining the free edge of the distal nail plate. Lunular anomalies include changes in form and structure and in color. Lunular dysmorphologic features can be characterized by macrolunula, microlunula or anolunula, and nonconvex lunula. Lunular dyschromias can be confluent or spotted or can be characterized by longitudinal colored bands that traverse the lunula. Alterations in the morphologic features or color (or both) of the lunula can be an indication of either a cutaneous or a systemic disorder.

The lunula is most pronounced on the thumb and not everyone's is visible. The lunula and the nail itself are good places to find warning signs of certain diseases such as liver disease, kidney disease, heart problems, and lung diseases.

The shape of the lunula determines the shape of the free edge (or the part of the nail that actually grows outward). Any color differences or unsual lines may indicate some type of disease or insufficiency.

Nails

Lunula (anatomie) Edit by --Special Forces 22:39, 5 July 2006 (UTC)