As a result of a congenital deformity, Dr. Hsu's hands and feet are curled inward. Although before going to America to pursue his studies, he already wore shoes that were made to order, they had to have very thick cotton padding to be comfortable, because his instep was contracted downward.
許倬雲的手腳天生向內卷曲，去美國唸書前，他穿的鞋子雖然也是訂做的，但都要將就「腳面攣縮朝下」的情況製鞋，再墊上很厚的棉花，才能稍感舒適。