An anal fissure???? That means he has a crack in his ass. It should say: Kaz Matsui expected to miss 4-5 days because he has a crack in his ass.
From Wikipedia: Most anal fissures are caused by stretching of the anal mucosa beyond its capability. Various causes of this fissure include: * Straining to defecate, especially if the stool is hard and dry * Severe and chronic constipation * Severe and chronic diarrhea * Crohn's disease and Ulcerative colitis * Tight sphincter muscles * Anal intercourse
Kaz is having surgery to fix the crack in his ass. From rotoworld: Kazuo Matsui will undergo surgery on Monday to repair an anal fissure. He needs this taken care of once and for all so we never have to think about it again. Matsui is expected to miss about two weeks, meaning he's probably not going to be ready for Opening Day. Mark Loretta and Geoff Blum could spend the first week filling in for him. Source: Astros.mlb.com http://www.rotoworld.com/content/playerpages/player_main.aspx?sport=MLB&id=3789