This is a gross abnormality of nail growth. This disorder usually affects the big toe nail:

• the nail of the great toe becomes greatly thickened and distorted
• usually seen in elderly patients
• may occur following trauma

Nail cutting with conventional nail clippers becomes nearly impossible. Onychogryphosis is probably caused by previous trauma to the nail bed.

Treatment:

• chiropody: grinding of the nail at regular intervals
• surgical: removal of the nail and ablation of the nail bed