Pincer nails are a nail disorder in which the lateral edges of the nail slowly approach one another, compressing the nailbed and underlying

dermis The dermis or corium is a layer of skin between the epidermis (skin), epidermis (with which it makes up the cutis (anatomy), cutis) and subcutaneous tissues, that primarily consists of dense irregular connective tissue and cushions the body from s ...

. It occurs less often in the fingernails than toenails.James, William; Berger, Timothy; Elston, Dirk (2005). ''Andrews' Diseases of the Skin: Clinical Dermatology''. (10th ed.). Saunders. . Hereditary pincer nails have been described, although the genes or mutations causing the hereditary form are unknown.

Signs and symptoms

Pincer nail is characterized by an increase in the nail's maximum transverse curvature, pushing the nail edges down into the lateral nail fold. The nail bed at the distal end along the longitudinal axis of the nail plate is also pushed down in a proximal to distal manner. The curvature that rises along the distal sides of the nail can cause individuals pain, persistent

inflammation Inflammation (from ) is part of the biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or irritants. The five cardinal signs are heat, pain, redness, swelling, and loss of function (Latin ''calor'', '' ...

, and recurring infections.

Causes

The cause of pincer nails is unknown, although it may be acquired or inherited. There have been several reports of hereditary pincer nails. Acquired pincer nails are asymmetrical in contrast to inherited pincer nails. Pincer nails are linked to a number of systemic conditions, such as

amyotrophic lateral sclerosis Amyotrophic lateral sclerosis (ALS), also known as motor neuron disease (MND) or—in the United States—Lou Gehrig's disease (LGD), is a rare, Terminal illness, terminal neurodegenerative disease, neurodegenerative disorder that results i ...

renal failure Kidney failure, also known as renal failure or end-stage renal disease (ESRD), is a medical condition in which the kidneys can no longer adequately filter waste products from the blood, functioning at less than 15% of normal levels. Kidney fa ...

, gastrointestinal cancers,

Kawasaki disease Kawasaki disease (also known as mucocutaneous lymph node syndrome) is a syndrome of unknown cause that results in a fever and mainly affects children under 5 years of age. It is a form of vasculitis, in which medium-sized blood vessels become in ...

, and

systemic lupus erythematosus Lupus, formally called systemic lupus erythematosus (SLE), is an autoimmune disease in which the body's immune system mistakenly attacks healthy tissue in many parts of the body. Symptoms vary among people and may be mild to severe. Common ...

Diagnosis

Clinical differential diagnoses are necessary due to confusion between pincer and ingrown nails. Pincer nails are recognized by their morphology, while ingrown nails are recognized by their symptoms. The biggest physical distinction between pincer and ingrown nails is that the former have a transverse curve of the long axis of the nail plate that grows from proximal to distal. Additionally, the contour of the nail plate in ingrown nails stays normal as the nail steadily grows in length.

Treatment

The goal of treatment is correcting the nail curvature in order to produce a nail that is aesthetically typical. There is no established course of treatment for pincer nails, but treatments can be conservative, surgical, and a combination of both. Conservative treatment is associated with recurrence/temporary remission and is a straightforward procedure. Surgical treatment has a decreased rate of recurrence, though when done improperly it can result in pain, an atypical nail appearance, secondary infection, wound necrosis, and sensory disruption.

Epidemiology

Pincer nail has an incidence rate of about 0.9% and usually affects the hallux toenails on the outer, inside, and bilateral sides. Fingernails and other toenails are rarely affected.

References

External links

VisualDx

Merck Manual
{{Disorders of skin appendages Conditions of the skin appendages