2008 ICD-9-CM Volume 1 Diagnosis Codes Home > Diseases Of The Digestive System 520-579 > Hernia Of Abdominal Cavity 550-553 > Inguinal Hernia 550.* > 2008 ICD-9-CM Diagnosis 550.90 Unilateral or unspecified inguinal hernia without obstruction or gangrene  On October 1, 2008 the 2009 ICD-9-CM codes came into effect. Therefore, this code may be out of date. The 2009 version of ICD-9-CM 550.90 can be accessed here. 550.90 is a specific code that can be used to specify a diagnosis View the ICD-9-CM Volume 1 550.* hierarchy ICD9Data's sister site ProcedureCodes.com launches with the 2008/09 CPT® codes - read more on the ICD9Data.com blog.