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Available at an institution. Many medical or surgical services are available in specialized or tertiary care facilities but not in smaller, rural, or less technologically developed hospitals or clinics.


(ŏn-tŏj′ĕn-ē) [Gr. on, being, + gennan, to produce] The developmental history of an organism, beginning with the germ cell(s).


(ŏn″ĭ-kĕk′tō-mē) [″ + ektome, to cut] Surgical removal of the nail of a finger or toe.


(ō-nĭk′ē-ă) [Gr. onyx, nail] Inflammation of the nailbed with possible suppuration and loss of the nail. SYN: matrixitis; onychitis. SEE: paronychia.


(ŏn″ĭ-kī′tĭs) [″ + itis, inflammation] Onychia.

onycho-, onych-

[Gr. onyx, stem onych-, nail] Prefixes meaning fingernail, toenail.


(ŏn″ĭ-kō-dĭs′trō-fē) [″ + dys, bad, + trophe, nutrition] Any maldevelopment of a nail.


(ŏn″ĭ-kō-grĭ-pō′sĭs) [″ + gryposis, a curving] Abnormal overgrowth of the nails with inward curvature.


(ŏn′ĭ-koyd) [″ + eidos, form, shape] Similar to a nail, esp. a fingernail.


(ŏn″ĭ-kŏl′ĭ-sĭs) [″ + lysis, dissolution] Loosening or detachment of the nail from the nailbed. SEE: photoonycholysis.


(on″i-kō-mī-kō′sĭs) [onycho- + mycosis] A fungal infection of the nails usually caused by Trichophyton and Tinea species and occasionally by Candida or other fungi. The hallmarks of the disease are thickening, scaling, and discoloration of the nailbed.

PATIENT CARE: Foot and nail care include keeping the feet and toes clean and dry, wearing fresh socks, changing shoes daily, and applying topical creams to the foot if the skin has cracked from athlete's foot. Paring away excessive nail growth ("debridement") reduces the thickness and length of affected nails and may enhance the effectiveness of medications. Some patients may have debridement performed professionally by a podiatrist.

Topical medications or oral (systemic) medications improve the appearance of fungal nail changes, but both are expensive and efficacy is only moderate. Oral antifungal drugs also carry the risk of liver damage and should be avoided by those with underlying liver compromise. Relapse rates after treatment are high. SYN: tinea unguium. SEE: illus.






(ŏn″ĭ-kō-ŏs″tē-ō-dĭs-plā′zē-ă) A genetic disease involving ectodermal and mesodermal tissues. The nails and patellae may be absent; other bones and joints are affected. SYN: nail-patella syndrome.


(ŏn″ĭk-ō-fō′sĭs) An accumulation of horny layers of epidermis under the toenail.


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