My sister’s son has some funny facial features (long thin face) and odd abilities. For example, when he puts his thumb across his palm and closes his fingers around the thumb, you can see the tip of his thumb poking out the other (baby finger) side. None of her other children and none of mine can do this. Am I making something out of nothing here or should his doctor take a look at these things?

You may be seeing some indications of a connective tissue disorder. The one that comes to mind first is something called Marfan syndrome. If you’ve ever seen a photograph of Abraham Lincoln you know he had a long, thin face. He was thin and tall, and he had long arms and long fingers.

There has been some thought that he might have had Marfan syndrome. All of these physical features are typical with Marfan syndrome. Newer evidence suggests he had a different (but very similar) disorder. But the association of Abraham Lincoln’s name with Marfan Syndrome has forever put this condition on the map.

There are a couple of physical tests that can be helpful in identifying Marfan syndrome. One is the positive thumb or Steinberg sign. The other is the positive wrist or Walker-Murdoch sign.

Your nephew may be demonstrating a positive thumb sign. Just as you described, if the patient puts the thumb across the palm and closes the fingers and the thumb pokes out the other (little finger) side, it’s a positive thumb sign. If the patient can circle the forearm with the thumb and little finger of the other hand and cover the entire nail of the little finger with the thumb, there is a positive wrist sign.

X-rays are an easy and fairly inexpensive way to look for evidence of Marfan syndrome. Besides the skeletal features already mentioned, the presence of acetabular protrusio is diagnostic. Acetabular protrusio means the acetabulum or hip socket is too deep and may protrude into the pelvis.

It’s a simple thing to ask the pediatrician or primary care doctor to take a look at the physical features. He or she will be able to see if they are significant or just the way your nephew is put together. If there is a problem, it’s better to find out sooner than later to prevent potential serious complications and ensure a healthy, long life.