1. Retronychia: Report of two cases
Maurice J. Dahdah, MD, Abdul Ghani Kibbi, MD, Samer Ghosn, MD 
Journal of the American Academy of Dermatology 
Volume 58, Issue 6, Pages (June 2008)
DOI: /j.jaad
Copyright © 2008 American Academy of Dermatology, Inc. Terms and Conditions

2. Fig 1
A, Case 1 at the time of presentation: massive subungual hematoma with paronychia. B, Following avulsion of the top nail, a yellowish lusterless underlying nail could be seen, along with three pyogenic granulomas.
Journal of the American Academy of Dermatology  , DOI: ( /j.jaad )
Copyright © 2008 American Academy of Dermatology, Inc. Terms and Conditions

3. Fig 2
A, Case 2 at the time of presentation: distal onycholysis with paronychia. B, Following avulsion, a yellow, dull, underlying nail was seen. C, Two months later, there was incomplete shedding of the dystrophic nail in (B) and persistence of the paronychia. D, Following avulsion of the dystrophic nail in (C), a white shiny underlying nail could be seen. E, The same healthy-looking nail, 3 months later, showing normal growth.
Journal of the American Academy of Dermatology  , DOI: ( /j.jaad )
Copyright © 2008 American Academy of Dermatology, Inc. Terms and Conditions

4. Fig 3
Diagram depicting the mechanism behind retronychia. Following trauma, complete onychomadesis may not occur, as the nail plate may remain held in the lateral wings of the nail matrix due to the curvature of those areas. With the growth of a new nail plate, the old one is pushed upwards and backwards, leading to embedding of the top nail into the ventral aspect of the proximal nail fold and secondary paronychia.
Journal of the American Academy of Dermatology  , DOI: ( /j.jaad )
Copyright © 2008 American Academy of Dermatology, Inc. Terms and Conditions