TY - CHAP M1 - Book, Section TI - Hernia A1 - Ahern, Gerard A1 - Brygel, Maurice Y1 - 2014 N1 - T2 - Exploring Essential Surgery AB - A hernia is an abnormal protrusion of an anatomical structure through a normal opening (hiatus hernia), defect (herniated disk) or weakness (direct inguinal hernia). It is suspected that there is an underlying change in the collagenous tissues. SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2021/03/04 UR - accesssurgery.mhmedical.com/content.aspx?aid=1167658342 ER -