There are a number of factors which can cause onycholysis, but records say the top two causes are physical trauma and psoriasis.
1. Physical traumas may include getting a finger smashed in a window or door, habitual finger sucking, nail biting, and using the nails as tools.
2. Psoriasis of the nails is common with people who have skin psoriasis. Only 5% of people with psoriasis of the nails do not have skin psoriasis, which means that 95% of those afflicted with psoriasis has onycholysis.
Other factors which can lead to onycholysis: