As with the majority of birth defects, scientists do not know why macrodactyly occurs, but information that is known about the condition indicates that it does not result from the mother's lifestyle or anything the mother did during her pregnancy.

Macrodactyly is more commonly considered static, with the enlarged digit (finger or toe) continuing to grow at the same rate as the normal digits of the hand, but it can be progressive, with the affected digits growing faster than the rest of the hand. In the static type, the involved digits are generally about 1 1D2 times the normal length and width of the normal digits. If the condition is progressive, the involved digit or digits can become enormous.

Hands are more commonly involved than feet. Most of the time, only one hand or one foot is affected, but usually more than one digit is involved. It may coexist with syndactyly, a condition in which two fingers or toes are fused together.

Macrodactyly can be associated with other conditions or can occur on its own. Although it is a benign condition, it is deforming and can be cosmetically displeasing to the child and family. Surgery, usually involving multiple procedures, can help the problem.

Although it occurs at birth, macrodactyly is not an inherited condition. It can occur in association with neurofibromatosis and vascular malformations. Children with multiple echondromatosis, Maffuci syndrome and tuberous sclerosis can have enlarged digits.

• X-rays- a diagnostic test that uses invisible electromagnetic energy beams to produce images of internal tissues, bones, and organs onto film.

• Magnetic Resonance Imaging (MRI) - a diagnostic procedure that uses a combination of large magnets, radiofrequencies and a computer to produce detailed images of organs and structures within the body.

• your child's age, overall health, and medical history
• whether the condition is static or progressive
• the severity of the condition
• any associated conditions
• your child's tolerance for specific medications, procedures, or therapies
• your opinion or preference

In mild cases, treatment for macrodactyly may involve observation or, in the case of an enlarged foot, shoe modification alone. Most of the time, however, surgery is required. It is important to understand that surgery to correct macrodactyly is complex because it involves multiple layers of tissue. It may take several different surgical procedures to achieve the desired result. Size altering surgery will involve extensive observation and planning, because doctors will want to be able to plot the rate of growth of your child's normal digits versus the enlarged digits. Your child's doctor may recommend some combination of the following surgical procedures:

• Soft tissue debulking: To help correct width, this procedure involves the surgical removal of the thickened layers of skin and fat and the replacement of skin with skin grafts harvested from healthy skin in the proximal region. This procedure is usually performed in several stages around three months apart. It is more often used to treat the milder forms of macrodactyly or as a part of the treatment of the more progressive forms.

• Shortening procedures: To help correct length, shortening procedures usually involve either surgical excision (removal) of one of the phalanges of the finger or toe, or removal of a metacarpal (hand bone) or metatarsal (foot bone).

• Ray resection: Surgical removal of the entire digit or digits is sometimes necessary, particularly when the condition is progressive. It is also an option if there is excessive widening of the forefoot, where digital shortening and debulking procedure may not be effective.