Watch glass nails R68.3

Enlarged, more convexly curved nail for pulmonary or cardiac cyanosis, see also flail finger. One-sided occurrence in aortic aneurysm, aneurysm of the subclavian artery or unilateral plexus paralysis. The nail is enlarged and rounded on all sides.

Most commonly, clock glass nails and drumstick fingers are signs of chronic lung disease (emphysema, bronchiectasis, chronic pulmonary tuberculosis) associated with tissue hypoxia (see also Marie-Bamberger syndrome).

A symmetric pattern of involvement may also be associated with chronic bowel disease and chronic liver disease.

Early manifestation of clock glass nails is a partial symptom of hereditary primary hypertrophic osteoarthropathy(pachydermoperiostosis).

In case of unilateral affection or affection of single fingers, circulatory disorders should be considered (e.g. arterio-venous fistulas).

Clock glass nails/drum flail fingers are also a partial symptom of the clinical picture in EMO syndrome ("exophthalmos, myxedema, osteoarthropathy").

Etiopathogenetically, the distension of the end phalanges is based on hypertrophy and fibrosis of the vascular connective tissue.

1. Herold G et al (2018) Internal Medicine 151, 338
2. Anschütz F (1978) The physical examination 167-168