This is one of the more common bony lesions of the foot.  It is a benign tumor of bone and cartilage. It is generally found underneath the toenail and may press upwards resulting in deformity of the nail plate and/ or soft tissues.  In severe lesions, the overlying tissues may ulcerate and become infected. This lesion responds well to surgical excision, and rarely reoccurs.

• Deformity and separation of the nail plate, expansion of the soft tissues
• Direct pressure on the nail may be painful
• Aggravated by wearing tight shoes.
• There may be signs of ulceration and infection.

• Cause is unknown, but believed to be trauma 

• Consult a podiatrist or physician
• Avoid tight fitting foot wear
• If an infection develops soak the foot in a basin of warm water two or three times a day.  Contact your podiatrist or physician immediately.
• Abnormal growths and  infections  require prompt professional attention.

• Take x-rays or perform other imaging to establish a correct diagnosis.
• If the toenail is causing problems, it may be removed
• Treat any infection present with antibiotics
• Surgically remove the exostosis
• Completely remove a deformed toenail so it will not grow back.

• Other, more serious, bone tumors may resemble an exostosis.  
• Evaluation by a trained practitioner is essential
• An infected ingrown toenail may resemble an ulceration from an exostosis
• Chronic in-growing nails can cause deformity of the nail plate and/or surrounding soft tissues.