Marfan syndrome is a genetic disease that often involves the eyes muscles, bones and cardiovascular system. It has some such features in appearance as very long limbs and high height, so such people are often selected as athletes again, and the disease is well known because of the premature death of some excellent athletes in the course of intense sports. There are some such characteristics in appearance, such as arm span greater than height, hands above the knees, and both ears hanging over the shoulders. There are also several other characteristics that can help determine this, such as the wrist sign, which is a positive wrist sign if the thumb can overlap the pinky finger when one hand is wrapped around the wrist of the other hand. Another one is to hold the thumb with four fingers, if the inter-thumb exceeds the ulnar margin, which is the palmar margin of the side where the little finger is located, you should also suspect this disease. If two people in the family have such a problem, it is even more important to suspect this disease, so you can use the external features to initially determine such a disease. There is also the nickname Spider Man, which you can imagine refers to the very long and slender limbs.