Though a person can be born with a hammertoe, it is generally not a birth defect, according to Mayo Clinic and Healthline.com. Usually, a hammertoe is caused when the middle joint of a toe is dislocated.
The reasons for this dislocation can include an injury to the toe, an unusually high arch to the foot, ill-fitting shoes and arthritis, according to Healthline.com. The ligaments or tendons in the foot can be tight enough to cause the dislocation, as can pressure from a bunion. Sometimes, damage to the spinal cord or the peripheral nerves can cause all the person's toes to curl downward.
Having the second toe longer than the big toe puts a person at greater risk for developing a hammertoe, according to Mayo Clinic. The risk also increases with age, and women are much more likely to develop a hammertoe than men.
Hammertoe is treatable, especially if the affected toe is still flexible, according to Mayo Clinic. In that case, the orthopedist suggests that the patient wear roomier shoes. She might also prescribe orthotics, or shoe pads to support the foot. She typically recommends exercises to strengthen the toe, such as picking up marbles with the toes. If these treatments do not work, surgery is used to release the tendon that is causing the toe to curl up, or bone is removed to let the toe straighten out.