A hammertoe is a toe that is bent all the time because of a weakened muscle. They can be hereditary, but can also be caused by shoes that are too short. The weakened muscle makes the tendons (tissues that connect muscles to bone) shorter, causing the toes to curl under the feet.
Bent Toe Disorders (Hammer, Mallet and Claw)
A bent toe disorder is an oddly bent toe joint. Hammer, claw and mallet toes are often painful and commonly occur in one or more of the four smaller toes.