Macrodactyly, which literally means large digit, is an uncommon condition that affects the fingers more commonly than the toes. Macrodactyly almost always affects only one extremity, often multiple digits. The index finger and long finger are affected most commonly, followed by the thumb. In some cases, the enlargement that is present at birth stays proportionally the same (static) while in other cases the enlargement continues to worsen with time (progressive).
An increased nerve or blood supply most commonly lead to the overgrowth, either of the digits (macrodactyly) or the entire limb. In most cases, macrodactyly is spontaneous and not a genetic condition. However, macrodactyly or limb overgrowth (also called hemihypertrophy) may be associated with a variety of syndromes. When we do not know the etiology of hemihypertrophy, a series of ultrasounds are often used to assure that the patient does not have a Wilms tumor. http://www.stjude.org/stjude/v/index.jsp?vgnextoid=5ceb061585f70110VgnVCM1000001e0215acRCRD
What follows is a partial listing of syndromes with a link for additional information:
Proteus syndrome http://ghr.nlm.nih.gov/condition/proteus-syndrome
Olliers disease (cartilage tumors) http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1592482/
Beckwith- Wiedemann syndrome http://ghr.nlm.nih.gov/condition/beckwith-wiedemann-syndrome
Klippel- Trenaunay syndrome (port wine stains) http://ghr.nlm.nih.gov/condition/klippel-trenaunay-syndrome
Surgery in Macrodactyly
The decision for surgery in macrodactyly and the decision of which surgery should be performed are both a challenge. In cases with nerve overgrowth, nerve decompression may become necessary as the large nerve becomes compressed causing symptoms similar to carpal tunnel syndrome (pain, loss of dexterity, numbness, etc). Vascular masses and bony overgrowth (Olliers) may require surgical debulking.
The most common macrodactyly situation in my experience is an enlarged digit with angulation, decreased motion, and an abnormal appearance. The best time for surgery is not obvious in most of these cases. One important goal is to avoid the scenario in which we perform one surgery after another over many years- essentially subjecting the child to numerous surgeries (with accompanying stress). To avoid this situation, very difficult decisions may be required including the possibility of excising the entire digit (or ray) when one or two digits are markedly enlarged- not an easy choice but often better than surgery after surgery.
If the digit is not terribly large, debulking the digit (often removing excess fat and skin) is a reasonable choice. Also we can slow the growth of the digit (at least one of the bones) and correct angulation with an osteotomy (cutting and angling the bone).
|Macrodactyly of the left thumb and index fingers.|
|Palm view of same patient with macrodactyly.|
|Long finger macrodactyly|
|Another long finger macrodactyly by x- ray. Not the size difference of the bones- both length and width.|
Recent patient below.
|Macrodactyly affecting only the index finger. The primary complaints are angulation, decreased motion, and enlargement.|
|Another view of the enlarged index finger in macrodactyly. The patient had surgery several years ago and there is a tight scar band on the inside (ulnar side) of the index finger contributing to the deformity.|
|Palmar view of the macrodactyly.|
This macrodactyly patient was observed and found to be worsening with time. She was taken to the operating room for treatment of the scar band (with a z- plasty or skin re- arrangement), debulking, and osteotomy of the bone to align it.
Charles A. Goldfarb, MD
Washington University School of Medicine