The imagery that is used in the opening description that the narrator gives us of Ethan Frome is very notable for the way that it presents him as a man who has suffered greatly and has become curiously detached from his community and almost imprisoned in life. Consider the following quote:
...it was the careless powerful look he had, in spite of a lameness checking each step like the jerk of a chain. There was something bleak and unapproachable in his face, and he was so stiffened and grizzled that I took him for an old man and was surprised to hear that he was not more than fifty-two.
What is notable in this quote is the reference to the lameness which makes it look as if Ethan Frome is walking around with a ball and chain attached to his leg. This image is of course very apposite when we remember how his marriage to his wife acts as just such a ball and chain, as it prevents him from achieving his dreams and living his life as he wants to. He is literally inhibited and restricted by this ball and chain, just as he is restricted by his lameness. The reference to his appearance and "bleak and unapproachable" nature likewise shows how he has been prematurely aged by his experience of life. All of this causes Ethan Frome to be the kind of character that made the narrator stop and take note of him when he first saw him.