Pathogenesis, Clinical Signs and Treatment Recommendations in Brittle Nails: A Review

Abstract

Nail plate brittleness (or fragility) is a common complaint affecting up to 20% of the population, especially women over 50 years of age, with fingernail fragility being more prevalent than toenail fragility. Nail brittleness is characterized by nails that split, flake and crumble, become soft and lose elasticity. The main clinical presentations are: onychoschizia, onychorrhexis, superficial granulation of keratin and worn-down nails. According to causative factors, we can distinguish 2 forms of nail fragility (NF): a primary "idiopathic or brittle nail syndrome" form and NF secondary to different causes such as inflammatory nail disorders, infections, systemic diseases and general conditions, traumas and alteration of the nail hydration. Optimal management requires treatment of the primary cause of brittle nails, when possible. In idiopathic NF oral supplementation, vitamins (especially biotin, also known as vitamin B7), trace elements and amino acids (especially cysteine) have been reported to be useful. In addition, several products, such as topical moisturizers and lacquers could be considered to restructure the affected nail plate and to reduce psychological impacts of this common problem.

Keywords: Aging; Nail brittleness; Nail cosmetic; Nail fragility; Onychorrhexis; Onychoschizia.

Fig. 1

Onychorrhexis: several longitudinal parallel furrows and thin fissures running on the superficial layer of the nail

Fig. 2

Onychorrhexis presenting as single longitudinal split of nail plate

Fig. 3

Lamellar onychoschizia: the free margin of the nail splits in horizontal layers

Fig. 4

Superficial granulation of keratin: the distal nail plate shows opaque white and fragile patches and striations

Fig. 5

Nail fragility due to nail matrix psoriasis: irregular pitting and brittle distal margin

Fig. 6

Nail fragility due to nail lichen planus: nail plate thinning, longitudinal fissuring and splitting of the nail plate

Fig. 7

Nail fragility due to alopecia areata of the nails: with regular thin onychorrhexis leading to trachyonychia

Fig. 8

Nail fragility due to hand eczema: nail plate thinning with diffuse scaling associated with periungual inflammatory signs

Fig. 9

Nail fragility due to white superficial onychomycosis: multiple white, opaque friable spots on the nail surface

Fig. 10

Nail fragility due to distal subungual onychomycosis: nail surface brittleness is evident in the distal nail

Fig. 11

Nail fragility due to mechanical trauma in onychotillomania: the distal margin of the nail has an irregular fragmented appearance with scaling

Fig. 12

Nail fragility due to chemical trauma by prolonged use of colored nail lacquer: yellow discoloration and onychorrhexis more marked in the distal nail