If you are OK with any translation for the moment, here is mine. Some paragraphs towards the end of the article related to the speculation of which type from the given length of rest and explanation of how the surgery is done. Plese feel free to make corrections.
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The comparatively long hospitalization and recuperation suggests Hanyu underwent a surgery to remove the urachal remnant, not just to remove pus. However, there is a question. He was complaining of a stomachache on 27th. That suggests the presence of inflammation, and in such a condition, they could not have done any kind of surgery. Because before surgery, the inflammation first needed to be managed by taking antimicrobial agents.
According to the media, he had a pain during the Grand Prix Final and after coming back to Japan, went to a doctor and was recommended a thorough examination. Considering above, we might be able to imagine this way: he had already been taking antimicrobial agents during the period. Although the pain was not completely blocked because of intense exercise at the competition, by 30th, he got ready for the surgery.
The removal of urachal remnant is not always necessary. But in his case, it can affect his performance at important competitions at any time. Therefore, it is most likely that he decided to remove it now.
Depending on the location, size, and form of the urachal remnant, the surgery sometimes cannot be done laparoscopically, and it has to be performed by opening the abdomen. If he had a choice, Hanyu must have a laparoscopic surgery which allows faster recovery.
[...] Given that he is a top athlete who will exercise very hard once leaving off the rest, he may need a longer recuperation time than ordinary people in order to be ready to go back to his hard practice. If that is the case, it is no surprise that he had a laparoscopic surgery and still needs the time to recover longer than usual. Also, since Hanyu has asthma, the damage after anesthesia might be greater than usual, which might also explain the given length of rest.
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