Risk factors, clinical variants and therapeutic outcome of retronychia: a retrospective study of 18 patients

Ultrasonographic Criteria for Diagnosing Unilateral and Bilateral Retronychia

“…Three US diagnostic criteria for retronychia were defined and analyzed according to digit and sex, which included a study of more than 200 nails as well as unilateral and bilateral afflictions. The most affected digits in this US study (big toes and index finger) were similar to the ones described in clinical reports, [1][2][3][4]11 which provide an idea of the real-world conditions of this research.…”

“…Retronychia is a nail disorder characterized by embedding of the proximal nail plate into the proximal nail fold, which clinically appears as an apparent halt to nail growth with a chronic proximal paronychia . It may be an underestimated condition that can appear after or concomitant to a severe illness, can be related to stress‐relevant situations, can be secondary to trauma, including sports injuries, or can appear as an idiopathic episode . Additionally, it has been reported that retronychia may have a similar etiology as Beau lines and onychomadesis.…”

“…So far, the diagnosis has been essentially clinical, which may represent a challenge because retronychia can easily mimic other nail disorders such as infections, psoriasis, tumors, and other common causes of nail dystrophy . Thus, because of its simulative nature, retronychia can generate several consultations to a wide range of specialists, which include dermatologists and orthopedic surgeons, and can demand consultations in emergency departments .…”

“…Moreover, this condition is usually unresponsive to only antibiotics, and commonly, management is surgical (onysectomy: ie, proximal avulsion of the nail) . Retronychia can appear in association with onychomadesis (ie, fragmentation of the nail plate), and since its original description in 1999, there have been an increasing number of case reports …”

“…11 Retronychia can appear in association with onychomadesis (ie, fragmentation of the nail plate), 5 and since its original description in 1999, 1 there have been an increasing number of case reports. [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] Ultrasonography (US) has been shown to be useful for supporting the diagnosis of this condition. [5][6][7][8][9][10] For example, a decreased distance between the origin of the nail plate and the base of the distal phalanx in comparison with the contralateral side has been reported in retronychia.…”