NAILS
Anatomy
1. Nail plate: is the hard and translucent
portion, composed of keratin
Its free edge is the part that
extends past the finger
2. Lunula : is the crescent
shaped whitish area of the nail bed
3. Eponychium or cuticle, is the fold of skin at
the proximal end of the nail
4. Nail fold : a fold of hard skin overlapping the
base and sides of the nail
5. Nail matrix : situated directly below the
cuticle. New cells form here to produce the nail
plate. It also contains blood vessels and nerves.
If the matrix is
damaged the nail
will grow deformed
6. Nail bed : It is
continuation of the
matrix and the part
that the nail plate
rests on
7. Hyponychium:
is the attachment between
the skin of the
finger or toe
and the distal
end of the nail
Nail growth and factors affecting it
• The nail can take between 5 - 6 months to
grow from the matrix to the free edge
• In children the growth is rapid 6 – 8 weeks
• In adults nails grow approximately by 1
mm a week
• Nail growth is quicker:
· During pregnancy
· In the summer than in the winter
· On the hands than the feet
• If the matrix is damaged by trauma, the
nail will grow back deformed
• Nail growth is inversely proportional to age
• With advancing years the nail plate
becomes paler and opaque and white
nails similar to those seen in cirrhosis,
uraemia and hypoalbuminaemia may be
seen in normal old persons
• Longitudinal ridging is present to some
degree in most people after 50 years of
age
I-Nail disorders
1.Congenital
2.Traumatic
3.Infectious
4.Neoplastic
1.Congenital
Anonychia
• Some or all the fingernails and toenails are
absent without significant bone anomalies
• It is a rare condition
and may have an
autosomal dominant
inheritance pattern
Nail patella syndrome
• A rare autosomal dominant syndrome
• There is a tetrad of fingernail dysplasia
with triangular lunula, absent or
hypoplastic patellae, posterior
iliac horns,
deformation
of the radial
heads
Pachyonychia congenita
• A rare autosomal dominant disease
• There is hypertrophy of the nails
associated in some cases with nail bed
and hyponychia hyperkeratosis
• May be associated with palmoplanter
hyperkeratosis,
warty skin lesions
on the limbs,
hyperhidrosis and
lustreless and
kinky scalp hair
2.Traumatic
Acute trauma
• It is classified
with respect to
severity, ranging
from a small
hematoma to
digit amputation
Chronic repetitive trauma
Nail biting
• It is found in 60% of children, 45% of
adolescents and 10% of adults
• The majority of moderate nail biters have no
associated psychiatric disorder
• Patients are susceptible to bacterial and viral
infections producing whitlows. It may also
result in the transportation of bacteria that
are buried under the surface of the nail, or
pinworms from anus region to mouth
• Regarding social effects the aesthetic aspect
of the nail may affect employability, selfesteem, and interaction with other people
• The nails are typically short, with up to 50% of
thenail bed exposed.
The free edge may
be even or ragged.
Surface change may
include splitting of the
nail into layers or a
sand-papered effect,
and the nail may acquire a
brown longitudinal streak
• Cure relies largely on the motivation of the
patient
• Local antiseptics and antimicrobial
ointments may help settle the infection
secondary to nail-unit damage
• Antidepressants and behavioural therapy
have been used with some success in
limited studies
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Hangnail
Trim the skin of the hangnail with a pair of clean
scissors.
These are due to hard
pieces of epidermis breaking
away from the lateral nail
folds
Although often due to nail
biting, they may result from
many other minor injuries
The splits may be painful when they penetrate
to the underlying dermis
They should be removed with sharp, pointed
scissors
Trauma by footwear
• Due to repetitive trauma by
footwear,the great toenail
becomes thickened, yellow
and twisted (onychogryphosis). It is most
commonly seen in
the elderly
• Treatment is either :
- Radical by surgical removal of the nail
and matrix and is recommended in young
persons with good circulation
- Palliative treatment requires regular
paring and trimming of the affected nails,
usually by a chiropodist
• Ingrowing toenail
• The lateral nail fold of the
great toe is penetrated
by the edge of the nail
plate, resulting in pain,
sepsis and, later, the
formation of
granulation tissue
• The main cause for the deformity is
compression of the toe from the side due to illfitting footwear
• In infancy, ingrowing toenail most commonly
occurs before shoes are worn, associated with
crawling, or wearing undersized jumpsuits
• Treatment is by:
-Avoiding tight-fitting or high-heeled shoes
- oral antibiotics or topical antibiotic ointments
combined with local anaesthetic agents help to
heal the toe faster and also provide pain relief
- Surgical removal of the ingrown toenail may
be required if the condition worsens
3-Nail infections
• Paronychia
• It is a soft tissue infection around a
fingernail
• It results from a breakdown of the protective
barrier between the nail and the nail fold
leading to entry of bacteria or fungi into the
area
• It is the most common hand infection
Etiology
Acute paronychia
• Usually results from a minor(e.g. nail biting)
trauma that breaks down the physical barrier
between the nail bed and the nail allowing
the infiltration of infectious organisms
• S. aureus is the most common infecting
organism. Organisms, such as
Streptococcus and Pseudomonas species,
gram-negative bacteria, and anaerobic
bacteria are other causative organisms
Chronic paronychia
• It is primarily caused by a mixture of C.albicans
and bacteria
• It can also be a complication of eczema
• Most often it occurs in persons whose hands
are repeatedly exposed to moist environments
or in those who have prolonged and repeated
contact with irritants such as mild acids, mild
alkalis, or other chemicals. People who are
most susceptible include housekeepers,
dishwashers, and swimmers
Clinically
Acute paronychia
• The presenting complaints
are pain, tenderness, and
swelling in one of the lateral
folds of the nail
• The affected area often
appears erythematous
and swollen
• In more advanced cases,
pus may collect under the
skin of the lateral fold
• If untreated, the infection can
extend into the eponychium,
both lateral folds and in severe
cases, the infection may track
proximally under the skin of the
finger and volarly to produce a
felon (whitlow) which is an
abscess involving the
bulbous distal end of a finger
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Chronic paronychia
Patients complain of symptoms lasting 6 weeks
or longer
The nail folds become swollen, erythematous,
and tender without fluctuance
Eventually, the nail plates become thickened
and discolored, with pronounced transverse
ridges
The cuticles and nail
folds may separate
from the nail plate,
forming a space for
the invasion of various
microorganisms
Treatment
Acute paronychia
• Oral antibiotics with gram-positive coverage
against S aureus, such as amoxicillin and
clavulanic acid (Augmentin) or clindamycin
(Dalacine C), are usually administered
concomitantly with warm water soaks 3-4
times/day
• Dalacine C and Augmentin also have
anaerobic activity; therefore, they are useful
in treating patients with paronychia due to
oral anaerobes contracted through nail biting
• If the paronychia does not resolve or if it
progresses to an abscess, it should be
drained promptly
Chronic paronychia
• The avoidance of moist environments or skin
irritants is essential for recovery
• Because of the 'mixed' etiology of the
inflammation, many clinicians use antibioticanticandida-steroid creams combinations.
Oral ketoconazole or fluconazole may be
added in more severe cases
• Patients with diabetes and those who are
immunocompromised need more aggressive
treatment because the response to therapy is
slower in these patients than in others
• Cryosurgery, using liquid nitrogen spray to
the nail folds, or surgical removal of the
proximal nail fold and adjacent part of the
lateral nail folds, may cure recalcitrant
cases
• Pseudomonas infection
• It is always a complication of onycholysis
or chronic paronychia
• The nail plate has a characteristic bluishblack or green color due to accumulation
of the pigment pyocyanin below the nail
which may remain after
the organism has been
removed
• Treatment is as described
for paronychia
• Gentamicin or sulphacetamide eye drops
can be used to eradicate the colonization
in resistant cases
4-Tumors
• Warts
• Fibrokeratoma:They
arise in the periunguium
and have a hyperkeratotic tip and narrow base
• Subungual exostosis: It is a
benign bony outgrowth
of the distal part of the toe
Glomus tumour:
There is pain, which may be
spontaneous or evoked by
mild trauma or temperature
change. Nail-plate changes
depend on the location of the
tumour. Matrix tumours cause
splitting and distortion of the
nail plate. Nail bed lesions are
most likely to appear as bluish
or red foci of 1-5mm diameter
beneath the nail
• Squamous cell carcinoma: There are hyperkeratotic, warty changes, erosions and
fissuring, macerated cuticle,
periungual swelling, erythema
• Melanocytic nevi: Present as
longitudinal melanonychia
Malignant melanoma:There are many
features that should suggest the possibility
of malignant melanoma:
• The presence of brown-black
periungual pigmentation
• The pigmentation develops in
a single digit in adult life
• The pigmentation is evolving to become
darker and broader and has blurred edges
• Longitudinal melanonychia(75% of cases)
Dermatoses affecting the nails
1-Psoriasis
• Psoriasis is the most common
disorder affecting fingernails
(50% of psoriatics)
• Pitting:Punctate surface depressions
• Onycholysis:Separation of
the nail from the nail bed
either proximally or distally
• Subungual hyperkeratosis:
most marked distally and
extends proximally
• Splinter hemorrhage:may be
due to the increased capillary
prominence and
in nail-bed dermis
2-Darier's disease
• There are white and red
longitudinal lines and
distal notching
3-Lichen planus
• Nail involvement occurs in 10% of
individuals with disseminated LP
• Nail apparatus involvement may be the
only manifestation
• One, several, or all 20 nails may be
involved ("twenty-nail syndrome," where
there is loss of all 20 nails without any
other evidence of lichen planus elsewhere
on the body)
• There is thinning of the nail plate and
longitudinal ridging
• Typically, the area of the
lunula is more elevated
than the more distal
portion
4-Alopecia areata
• The nail plate is rough
with a "hammered brass"
appearance
5-Eczema
• Severe pompholyx
around the nail folds
may cause nail
dystrophy, resulting
in irregular ridges
Nail signs in systemic disease
I-Abnormalities of shape
1-Clubbing
• It is the bulbous uniform swelling of the soft
tissue of the terminal
phalanx of a digit with
subsequent loss of the
normal angle between
the nail and the nail bed
• It is due to vasodilation of the digit blood
vessels, the cause of which is unknown
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Causes :
1-Primary (idiopathic)clubbing e.g. familial
clubbing
2-Secondary clubbing include the following:
Pulmonary disease e.g. Lung cancer, cystic
fibrosis
Cardiac disease e.g. Cyanotic congenital
heart disease
GIT disease e.g. inflammatory bowel disease
Skin disease e.g. Pachydermoperiostosis
Malignancies e.g. Thyroid cancer, Hodgkin
disease, leukemia
Miscellaneous conditions e.g. Acromegaly,
pregnancy, and hypoxemia possibly related
to long-term smoking of cannabis
2-Koilonychia
• Nails become concave (spoon-shaped)
• It is common in infancy as a benign feature
of the great toenail
• The most common
systemic association
is with iron deficiency
II-Changes in nail surface
Beau's lines
• They are deep grooved lines
that run from side to side on
the fingernail due to a temporary cessation of cell division
in the nail matrix
• This may be caused by an
infection or trauma in the
nail matrix
Beau's
lines
Any severe systemic illness that disrupts nail growth, Raynaud's disease, pemphigus,
trauma
• Systemic reasons include: coronary
occlusion, hypocalcaemia, diabetes,
certain drugs - including beta blockers
Muehrcke's lines:
• They are superficial (not grooved as beau’s line)
white lines that extend all the way across the
nail and lie parallel to the lunula
• The lines are actually in the
vascular nail bed
underneath the nail plate,
and so they do not move
with nail growth and
disappear when pressure
is placed over the nail
• The appearance of Meuhrcke's lines is
nonspecific, but they are often associated
with decreased protein synthesis, which
may occur during periods of metabolic
stress (e.g., after chemotherapy) and in
hypoalbuminemic states such as the
nephrotic syndrome
• 'True' Leukonychia
• It is the most common form of leukonychia,
small white spots affecting one or two nails
• Picking and biting of the nails are a prominent
cause in young children
and nail biters
• In most cases, they
disappear after around
eight months, which is
the amount of time
necessary for nails to
regrow completely
III-Changes in nail color
Terry’s nails
• The nails are white proximally and normal
distally
• It occurs in cirrhosis,
congestive heart
failure and adultonset diabetes
• Yellow nail syndrome
• The nails are yellow due to
thickening, sometimes with
a tinge of green
• The lunula is obscured and
there is increased transverse
and longitudinal curvature
and loss of cuticle
• It is usually accompanied by
lymphoedema and pleural
effusions
Color changes due to drugs
• Chloroquine may produce blueblack pigmentation of the nail
• Arsenic may produce
longitudinal bands of pigment
or transverse white stripes (Mees' stripes)
across the nail
Nail cosmetics
• Professional taking care of the fingernails
is known as a manicure
• Professional taking care of the toenails is
known as a pedicure
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Nail polish
• In 1930, Charles Revson developed the
first pigmented, opaque nail polish, which
launched Revlon
• Nail polish basically consists of pigments
suspended in a volatile solvent to which
film formers have been added. The
ingredients are as follows:
• 1-Cellulose film formers, such as
nitrocellulose. These give gloss, body and
gel structure
• 2-Resins, such as toluene sulphonamide
formaldehyde resin, to improve the gloss and
adhesion of the film
• Plasticizers, such as dibutylphthalate, added
to give the film pliability, to minimize
shrinkage, and soften and plasticize the
cellulose
• 4-Suspending agents, such as bentonite, for
non-settling and flow. They keep pigments in
suspension on shaking
• 5-Solvents (such as butyl) and diluents
(such as toluene), which keep other
ingredients in a liquid state and control the
application and drying time
• 6-Color substances. These are either
inorganic (iron oxides) or a variety of
certified organic colors (D and C yellow,
A1 lakes). In principle, they require to be
insoluble in a nail lacquer system
Problems of nail polish
1-Contact dermatitis
• Frequently appears on any part of the
body accessible to the nails, with no signs
in or around the nail
The commonest areas
involved are the eyelids,
the lower half of the face,
the sides of the neck and
the upper chest
• Formaldehyde resin is
the most common cause
• 2-Nail plate discoloration:
• Nail-plate staining from the use of polish is
most commonly yellow-orange in color
• 3-Nail polish removers:
• These are composed of various solvents
such as acetone which occasionally cause
trouble by excessive drying of the nail
plate and may be responsible for some
inflammation of nail folds