Subungal Exostosis (Bone Spur under Toenail)
Subungal exostosis is more commonly referred to as a bone spur under the toenail. This condition is generally caused by toe trauma, which results in the formation of a bony irregularity or prominence. The normal treatment for subungal exostosis is surgical removal. Other small tumors, called osteochondromas and enchondromas, can also form in the bone beneath the toenail.