What is the term for the tissue beneath the distal end (free edge) of the nail?

The tissue beneath the distal end, or free edge, of the nail is known as the hyponychium. This structure serves an important function by acting as a barrier, preventing bacteria and other potential pathogens from entering the nail bed and underlying tissues. It is composed of soft tissue and keratin, helping to provide protection and support to the nail.

The hyponychium differs from the cuticle, which is the layer of skin at the base of the nail that overlaps the nail plate and serves to protect the area from infection. The lunula refers to the visible part of the nail matrix at the base of the nail, often seen as a pale crescent shape. The matrix itself is the tissue that generates the nail plate, not located beneath the free edge. Understanding these terms and their functions helps to grasp the anatomy and care involved in nail health.