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Nail disease

Nail disease is a biology topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Nail disease rather than just read about it. In short: A nail disease or onychosis is a disease or deformity of the nail. Although the nail is a structure produced by the skin and is a skin appendage, nail diseases have a distinct classification as they have their own signs and symptoms which may relate to other medical conditions.

Nail disease — main illustration
Nail disease — illustration

Key takeaways

  • Nail disease belongs to biology; place it in that map before memorising details.
  • Learn the definition first, then one example that makes the definition concrete.
  • Connect Nail disease to a quantity you can measure, compute or draw — that is where exam questions come from.
  • Reproduce the core statement of Nail disease from memory before moving on to harder problems.

Reference excerpt

A nail disease or onychosis is a disease or deformity of the nail. Although the nail is a structure produced by the skin and is a skin appendage, nail diseases have a distinct classification as they have their own signs and symptoms which may relate to other medical conditions. Some nail conditions that show signs of infection or inflammation may require medical assistance.

Diseases

Onychia is an inflammation of the nail folds (surrounding tissue of the nail plate) of the nail with formation of pus and shedding of the nail. Onychia results from the introduction of microscopic pathogens through small wounds. Onychocryptosis, commonly known as "ingrown nails" (unguis incarnatus), can affect either the fingers or the toes. In this condition, the nail cuts into one or both sides of the nail bed, resulting in inflammation and possibly infection. The relative rarity of this condition in the fingers suggests that pressure from the ground or shoe against the toe is a prime factor. The movements involved in walking or other physical disturbances can contribute to the problem. Mild onychocryptosis, particularly in the absence of infection, can be treated by trimming and rounding the nail. More advanced cases, which usually include infection, are treated by surgically excising the ingrowing portion of the nail down to its bony origin and thermally or chemically cauterizing the matrix, or 'root', to prevent recurrence. This surgery is called matrixectomy. The best results are achieved by cauterizing the matrix with phenol. The Vandenbos Procedure is a highly effective method that focuses on excision of excessive nail fold tissue without affecting the healthy nail and nail matrix. The Vandenbos Procedure is showing high success rates in eliminating onychocryptosis without altering the normal nail. Another, much less effective, treatment is excision of the matrix, sometimes called a 'cold steel procedure'.

Onychodystrophy is a deformation of the nails that can result from cancer chemotherapy which includes bleomycin, hydroxyurea, or 5-fluorouracil. It can include discoloration of the nail, or dyschromia. Onychogryposis, also called "ram's-horn nail", is a thickening and increase in curvature of the nail. It is usually the result of injury to the matrix. It may be partially hereditary and can also occur as a result of long-term neglect. It is most commonly seen in the great toe but may be seen in other toes as well as the fingernails. An affected nail has many grooves and ridges, is brownish in color, and grows more quickly on one side than on the other. The thick curved nail is difficult to cut, and often remains untrimmed, exacerbating the problem.

Onycholysis is a loosening of the exposed portion of the nail from the nail bed, usually beginning at the free edge and continuing to the lunula. It is frequently associated with an internal disorder, trauma, infection, nail fungi, allergy to nail enhancement products, or side effects of drugs. Onychomadesis is the separation and falling off of a nail from the nail bed. Common causes include localized infection, minor injury to the matrix bed, or severe systemic illness. It is sometimes a side effect of chemotherapy or x-ray treatments for cancer. A new nail plate will form once the cause of the disease is removed. Onychomycosis, also known as tinea unguium, is a contagious infection of the nail caused by the same fungal organisms which cause ringworm of the skin (Trichophyton rubrum or T. mentagrophytes, rarely other trichophyton species or Epidermophyton floccosum ). It can result in discoloration, thickening, chalkiness, or crumbling of the nails and is often treated by powerful oral medications which, rarely, can cause severe side effects including liver failure. Mild onychomycosis sometimes responds to a combination of topical antifungal medication, sometimes applied as special medicinal nail lacquer, and periodic filing of the nail surface. For advanced onychomycosis, especially if more than one nail is infected, systemic medication (pills) is preferred. Home remedies are often used, although their effectiveness is disputed.

Onychophosis is a growth of horny epithelium in the nail. Onychoptosis is the periodic shedding of one or more nails, in whole or part. This condition may follow certain diseases such as syphilis, or can result from fever, trauma, systemic upsets or adverse reaction to drugs. Onychorrhexis also known as brittle nails, is brittleness with breakage of fingernails or toenails. Paronychia is a bacterial or fungal infection where the nail and skin meet. Koilonychia is when the nail curves upwards (becomes spoon-shaped) due to an iron deficiency. The normal process of change is: brittle nails, straight nails, spoon-shaped nails. Subungual hematoma occurs when trauma to the nail results in a collection of blood, or hematoma, under the nail. It may result from an acute injury or from repeated minor trauma such as running in undersized shoes. Acute subungual hematomas are quite painful, and are usually treated by releasing the blood by creating a small hole in the nail. Drilling and thermal cautery are common methods for creating the hole. Thermal cautery is not used on acrylic nails because they are flammable. Onychomatricoma, a tumor of the nail matrix. Nail pemphigus, an auto-immune disease. Erythronychia, red bands in the nail from some inflammatory conditions. Melanonychia, a black, brown or grey discoloration of the nail, with numerous causes.

Nail changes and conditions associated with them Nail inspection can give hints to the internal condition of the body as well. Nail disease can be very subtle and should be evaluated by a dermatologist with a focus in this particular area of medicine. A nail technician may be the first to note a subtle change in nail health.

Pliability Brittleness is associated with iron deficiency, thyroid problems, and impaired kidney function. Splitting and fraying are associated with psoriasis and deficiencies of folic acid, protein, and Vitamin C. Unusual thickness is associated with circulation problems.

… excerpt ends here. Continue reading the full article.

Illustrations

Nail disease illustration
Nail disease: Anatomy of the basic parts of a human nail. A. Nail plate; B. lunula; C. root; D. sinus; E. matrix; F. nail bed; G. eponychium; H. free margin.
Anatomy of the basic parts of a human nail. A. Nail plate; B. lunula; C. root; D. sinus; E. matrix; F. nail bed; G. eponychium; H. free margin.
Nail disease: Ingrown nail in hallux toe
Ingrown nail in hallux toe
Nail disease: Onychomycosis in every nail of the right foot.
Onychomycosis in every nail of the right foot.
Nail disease: Subungual hematoma (mild)
Subungual hematoma (mild)

Worked examples

Example 1 — a first encounter with Nail disease

Start with the simplest possible case. Write down what Nail disease claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In biology, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Nail disease before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Nail disease ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Nail disease

In research
Nail disease appears in biology research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry
Engineering practice reuses Nail disease in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom
Nail disease is common in secondary-school and first-year university syllabi. It links to neighbouring topics Conditions of the skin appendages, Nails (anatomy), so understanding it makes those chapters shorter.
In everyday life
Look for Nail disease outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.
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How to study Nail disease in 20 minutes

  1. Read the reference excerpt below once, without taking notes.
  2. Close the page and write down what Nail disease means in your own words.
  3. Compare your version with the excerpt and mark what you missed.
  4. Work through the three examples above with pen and paper.
  5. Explain Nail disease out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Nail disease in simple terms?

A nail disease or onychosis is a disease or deformity of the nail. Although the nail is a structure produced by the skin and is a skin appendage, nail diseases have a distinct classification as they have their own signs and symptoms which may relate to other medical conditions.

Why does Nail disease matter?

Because it connects several biology ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Nail disease?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Nail disease.

Tags

  • Conditions of the skin appendages
  • Nails (anatomy)

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