Hypertrophy without deformity of whole nail plate. Nail appears more opaque than normal translucent pink appearance.
Thickening occurs at matrix.
Subungual hyperkeratosis and debris is common
May be associated with minor repetitive trauma to the nail or acute trauma. May be caused by fungal infection. Poor circulation in the elderly has been associated with it.
Believed that trauma to the nail matrix results in increased production of onchyocytes.
Most commonly, only the hallux is involved – but others can be involved (all nails or isolated nails).
Nail cutting is difficult and shoe pressure may cause pain. Pressure may result in a subungual aseptic necrosis.
Differential diagnosis - onychomycosis
Management – regular reduction of nail plate with nail cutters and nail drill/burr or permanent surgical removal of nail.