d. The surface of the skin has many ridges and grooves. These, in effect, form
miniature suction cups.
e. Deep in the palm and sole, there is a very dense FCT, referred to as the
palmar aponeurosis and plantar aponeurosis. A thickened subcutaneous layer firmly
attaches the modified integument to the underlying aponeurosis.
Section XI. VARIATIONS IN PENETRATION
3-41. VARIATIONS IN INFANTS AND THE ELDERLY
In infants and the elderly, substances more readily penetrate the skin than with
other age groups. One such substance is hexachlorophene. Hexachlorophene is an
ingredient in some soaps and detergents used to maintain a germ-free environment in
the hospital. If the skin of the infant or elderly person is not thoroughly rinsed after the
use of such soaps or detergents, the skin of these individuals will readily absorb the
residual hexachlorophene. This may produce neurological damage.
3-42. VARIATIONS ACCORDING TO BODY AREA
This condition may also exist in other age groups in those areas where the skin is
thinnest. These areas include the inner surfaces of the flexing joints, axillae, and groin
and particularly the areas between the fingers and toes.