Hammer toes are a condition of the proximal interphalangeal joint of the second, third, fourth or fifth toe. The condition makes the toe permanently bent, and resembles a hammer. The mallet toe is a very similar issue which affects the distal joint area. Some people are born with these issues. Usually, these issues happen due to the wear of poorly fitting shoes that often force the toe to bend (particularly high heels) or shoes which are too narrow or short.