system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Pteryigum of nail is seen in -
assistant
The correct answer is  Ans. is 'a' i.e., Lichen planusDorsal pterygiumo Winged appearance of nail due to a central fibrotic band divides a nail proximally in two.o Fibrotic band obstructs normal nail growth, eg lichen planusVentral pterygium or ptery gium inversum unguiso Occurs on the distal undersurface of the nail, with forward extension of the nail bed epithelium dislocating the hyponychium and obscuring the distal groove.eg:- trauma, systemic sclerosis, Raynaud's phenomenon, lupus erythematosus, familial and infective