What abnormality is present?
Macrodactyly (i.e. big finger), a form of localised gigantism.
What are some of the causes of true macrodactyly?
Macrodystrophia lipomatosa and Proteus syndrome.
What are some conditions that can mimic localised gigantism (i.e. they cause apparent overgrowth of a region, but not due to merely hypertrophied local tissues)?
Neurofibromatosis type 1 (NF1), fibrolipomatous hamartoma of the median or ulnar nerve, vascular malformations (e.g. haemangioma, including Maffucci syndrome, arteriovenous malformation (AVM), Klippel-Trenaunay-Weber syndrome), chronic hyperaemia (e.g. juvenile rheumatoid arthritis, haemophilia).
What is the prognosis of macrodystrophica lipomatosa?
Although macrodystrophia lipomatosa is considered a progressive form of macrodactyly (i.e. the growth of the affected parts is faster than the rest of the body) growth halts at puberty.
Radiographs of the left hand of a child demonstrate marked hypertrophy of the middle finger, with associated enlargement of the phalanges. There is no soft tissue calcification or focal osseous mass.