Polymetatarsia

Polymetatarsia

An example of polymetatarsia with hexadactyly.

Polymetatarsia is a rare congenital condition characterized by the presence of an extra metatarsal bone in the foot. This condition often occurs in conjunction with polydactyly, where there is an additional toe present. Polymetatarsia can affect one or both feet and may vary in its presentation and severity.

Anatomy and Pathophysiology

In a typical human foot, there are five metatarsal bones, each corresponding to one of the five toes. In polymetatarsia, an additional metatarsal bone is present, which can lead to the formation of an extra toe. This condition is often associated with hexadactyly, where there are six toes on one foot.

The development of polymetatarsia is believed to occur during fetal development, where an error in the segmentation of the limb bud leads to the formation of extra bones and digits. The exact genetic and environmental factors contributing to this condition are not fully understood, but it is thought to involve complex interactions between multiple genes and possibly environmental influences.

Clinical Presentation

Patients with polymetatarsia may present with a variety of symptoms, depending on the severity and configuration of the extra metatarsal and toe. Common clinical features include:

• Presence of an extra toe (polydactyly)
• Abnormal foot shape
• Difficulty in wearing shoes
• Pain or discomfort during walking or physical activity

The condition can be diagnosed through physical examination and confirmed with imaging studies such as X-rays, which reveal the presence of an additional metatarsal bone.

Treatment

The management of polymetatarsia depends on the severity of the condition and the symptoms experienced by the patient. In cases where the extra toe and metatarsal cause significant discomfort or functional impairment, surgical intervention may be considered. Surgical options include:

• Removal of the extra metatarsal and toe
• Reconstruction of the foot to improve function and appearance

Post-surgical rehabilitation may be necessary to ensure optimal recovery and function.

Prognosis

The prognosis for individuals with polymetatarsia is generally good, especially if the condition is treated surgically. Most patients can achieve normal or near-normal foot function and appearance following appropriate intervention. However, untreated polymetatarsia can lead to chronic pain, difficulty in ambulation, and other complications.

Related Pages

• Polydactyly
• Congenital limb deformities
• Foot anatomy