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The separation or loosening of a fingernail or toenail from its nail bed.

[New Latin : Greek onux, onukh-, nail, claw; see onyx + -lysis.]
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.onycholysis - separation of a nail from its normal attachment to the nail bed
onychosis - any disease or disorder of the nails
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References in periodicals archive ?
Lupus erythematosus vasculitis in the nail bed can also give rise to onycholysis.
The second stage affects the palms and soles with keratoderma, fissures, and onycholysis and dystrophy of the nails.
Nail involvement was in the form of pigmentation, transverse ridges, Beau's lines, onychomadesis and onycholysis and corresponded to the extent of severity of the disease.
Psoriasis can also cause changes to the nails, such as pitting or onycholysis, hyperkeratosis under the nails, and horizontal ridging.
Physical examination revealed a red subungual mass with crust on top and onycholysis [Figure 1]a and [Figure 1]b.
Changes occur at the distal and proximal portions of the nail bed in onycholysis and onychomadesis, respectively.
The toenail of the right foot great toe has thickening of the distal part of the nail, with onycholysis (separation of the nail plate from the nail bed), yellow discoloration, and subungual debris.
Fingernail changes, including pitting of the nails, onycholysis and nail dystrophy, were observed in 72.
Differential Diagnosis of Onychomycosis (18-21) * Nail trauma * Psoriasis * Lichen planus * Paronychia * Bacterial infection * Pachyonychia congenita * Nail bed tumors (squamous cell carcinoma) and verrucae * Yellow nail syndrome * Alopecia areata * Contact/atopic dermatitis * Idiopathic onycholysis * Twenty-nail dystrophy (trachyonychia) * Nail changes associated with systemic disease or nail cosmetics
1) It is an uncommon subset of psoriatic arthritis that is characterized by psoriatic onychodystrophy, onycholysis, connective tissue thickening above the distal phalanx as well as specific radiologic changes such as periosteal reaction and bone erosions of the distal phalanges.