Onychoschizia

Onychoschizia
Other namesLamellar nail splitting, Brittle nails (lamellar type)
SpecialtyDermatology
SymptomsHorizontal layering and peeling of the distal free edge of the nail
CausesRepeated water and chemical exposure, nail cosmetics, ageing
Diagnostic methodClinical
Differential diagnosisOnychorrhexis, onychomycosis, nail psoriasis, lichen planus
TreatmentMoisturizers, avoidance of irritants
FrequencyVery common, especially in women

Onychoschizia (from Ancient Greek ὄνυξ ónyx "nail" and σχίζω schízō "to split") is a common nail disorder characterized by lamellar splitting — horizontal layering and peeling of the distal (free) edge of the nail plate. It is one of the two main types of brittle nails, the other being onychorrhexis (longitudinal splitting).

Clinical presentation

The condition typically presents with thin horizontal layers that peel away at the free edge of the nail, often giving a white, frayed, or ragged appearance. It most commonly affects the fingernails and usually involves multiple nails. It is frequently part of the broader brittle nail syndrome.

Causes

The most common cause is repeated exposure of the nails to water and drying agents. Other contributing factors include:

  • Frequent hand washing, soaps, and detergents [1]
  • Nail cosmetics (nail polish, acetone-based removers)
  • Aggressive manicures or nail filing
  • Ageing (natural dehydration of the nail plate) [1]
  • Nutritional deficiencies (iron, zinc, biotin)
  • Certain dermatological conditions such as psoriasis and lichen planus may feature such nails.[1]
  • nail biting, and repeated trauma such as typing, can contribute to nail splitting.[2] Dehydration likely plays a role.[1] Nutritional deficiencies that can result in nail splitting include iron, selenium, and zinc.[2]

Diagnosis

Diagnosis is by its appearance, but sometimes blood tests are required to look for iron deficiency, thyroid problems, and kidney problems.[2]

Treatment

Treatment focuses on protection and hydration of the nail:

  • Avoidance of irritants (water, chemicals, harsh nail products)
  • Regular application of moisturizing creams containing urea or glycerin [3]
  • Wearing gloves during wet work
  • Biotin supplementation (2.5–5 mg daily) may be beneficial in some cases, particularly if a deficiency is present [2]
  • An acceptable alternative is gel nails.[3]

Other animals

It also occurs in hooved animals such as horses.[4]

See also

References

  1. 1 2 3 4 Johnstone, Ronald B. (2017). "2. Diagnostic clues and "need-to-know" items". Weedon's Skin Pathology Essentials (2nd ed.). Elsevier. p. 31. ISBN 978-0-7020-6830-0.
  2. 1 2 3 4 Sloan, Brett (2022). "16. Multiple nail: nail splitting". In Waldman, Reid A.; Grant-Kels, Jane M. (eds.). Dermatology for the Primary Care Provider. Philadelphia: Elsevier. pp. 277–278. ISBN 978-0-323-71236-1.
  3. 1 2 James, William D.; Elston, Dirk; Treat, James R.; Rosenbach, Misha A.; Neuhaus, Isaac (2020). "33. Diseases of the skin appendages". Andrews' Diseases of the Skin: Clinical Dermatology (13th ed.). Edinburgh: Elsevier. p. 785. ISBN 978-0-323-54753-6.
  4. ↑ Colombo, Victor E.; Gerber, Françoise; Bronhofer, Max; Floersheim, George L. (December 1990). "Treatment of brittle fingernails and onychoschizia with biotin: Scanning electron microscopy". Journal of the American Academy of Dermatology. 23 (6): 1127–1132. doi:10.1016/0190-9622(90)70345-i. PMID 2273113.