Complex sentence: An occasional side-effect of the operation is the formation and tangling of fibrous bands from near the site of the operation with other parts of the bowel-these can lead to bowel infarction if not operated on.
Split into simpler sentences: An occasional side-effect of the operation is the formation and tangling of fibrous bands from near the site of the operation with other parts of the bowel. These can lead to bowel infarction if not operated on.