Title: Macrodystrophia Lipomatosa

Imaging Findings:

Figure Plain film of the hand shows splayed, long broad phalanges with enlargement of the first and second digits (arrows).

Figure MRI of the same patient reveals an enlarged digit with disproportionate adipose tissue (arrows).

Figure Separate patient showing enlargement of the second digit of the foot.

Clinical:

Present during adolescence as mechanical and degenerative changes begin to impair joint function and cause compression of neurovascular structures. Most commonly involves the hand in the median nerve distribution. As illustrated above, can also be seen in the feet.

Etiology:

Congenital, progressive overgrowth of mesenchymal elements with disproportionate adipose tissue. Growth ceases at puberty. Not uncommonly associated with a hamartoma of the supplying nerve.

References:

1. Gupta MD, et al. Macrodystrophia lipomatosa: radiographic observations. Brit. J. Radiol.1992; 65:769-773.
2. Goldman AB, Kaye JJ. Macrodystrophia Lipomatosa: radiographic diagnosis. Am J Roentgenology 1987; 128:101-105.
3. Blacksin M, et al. MR diagnosis of macrodystrophia lipomatosa. Am J Roentgenology 1992; 158:1295-1297.