Hammertoes form when a foot muscle gets weak. The weakness may be from diabetic nerve damage. The weakened muscle makes the tendons in the foot shorter and makes the toes curl under the feet. You may get sores on the bottoms of your feet and on the tops of your toes. The feet can change their shape.
Hammertoes can cause problems with walking and finding shoes that fit well.
Hammertoes can run in the family. Wearing shoes that are too short can also cause hammertoes. Dry and cracked skin can happen because the nerves in your legs and feet do not get the message to keep your skin soft and moist. Dry skin can become cracked and allow germs to enter. If your blood sugar is high, sugar feeds the germs and makes the infection worse.