No, two nails cannot grow together in the typical sense of two separate nail plates fusing. However, a condition called retronychia can cause the appearance of two nails growing on top of each other. This happens when a new nail plate grows under an existing one due to misalignment of the nail matrix and the old nail plate. The old nail plate remains, and new nail growth occurs underneath. This creates a stacked appearance, resembling two nails growing together.
Understanding Retronychia and Nail Growth
- Nail Matrix: The nail matrix is responsible for nail growth. Damage or misalignment of this structure can lead to abnormal nail growth. Nail Matrix: What It Is, Function, Damage & Conditions
- Retronychia: This condition results in a new nail plate forming beneath the old one. [Retronychia occurs when the nail plate (the hard part of the nail made of the protein keratin) grows into the nail fold. Multiple generations of new nail plates can then grow on top of one another in a stack under the old nail plate because the nail matrix and the old nail plate are no longer aligned.]
- Causes: Retronychia can be caused by repeated micro-trauma, such as from tight shoes or repetitive activities. Usually it's caused by repeated micro trauma, either from jogging a lot, or wearing a pair of shoes that are too short. The micro trauma injures…
Other Nail Conditions Mimicking Two Nails
While retronychia is the primary condition causing the visual appearance of two nails, other nail changes can cause similar confusion:
- Ingrown toenails: An ingrown toenail can sometimes appear as if there are two nails, especially if it curls and grows back into the skin. Ingrown Toenails: Signs, Causes, Treatment & Prevention
- Nail trauma: Trauma to the nail can disrupt its growth, possibly leading to irregularities that might be misinterpreted as multiple nails. Nail Deformities and Dystrophies - Merck Manual Professional Edition
Conclusion
The appearance of two nails growing together is typically due to a condition like retronychia, not a true fusion of two nails. Other nail disorders can sometimes create a similar visual effect.
