2027 ICD-10-CM Diagnosis Code K40.40Unilateral inguinal hernia, with gangrene, not specified as recurrent
ICD-10-CM Codes›K00–K95›K40-K46›K40
- Billable — Valid for Submission
- MCC — Major Complication or Comorbidity
- Not Chronic
K40.40 is a billable ICD-10-CM diagnosis code for unilateral inguinal hernia, with gangrene, not specified as recurrent. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 393 through 395, 791, 793. As a secondary diagnosis, it counts as a major complication or comorbidity (MCC) and places an inpatient stay in the highest severity level of its MS-DRG family. It does not count, however, when the principal diagnosis is one of 18 closely related codes. Coders also document this condition as inguinal hernia with gangrene. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Abdominal hernia and Gangrene.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Inguinal hernia with gangrene
- Left inguinal hernia with gangrene
- Obstructed inguinal hernia with gangrene
- Obstructed left inguinal hernia
- Obstructed left inguinal hernia with gangrene
- Obstructed right inguinal hernia
- Obstructed right inguinal hernia with gangrene
- Right inguinal hernia with gangrene
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to K40.40: its own notes plus those printed at K40, block K40-K46, and Chapter 11. A note printed at a category, block or chapter applies to every code under it.
Includes
Further defines, or gives examples of, the content of the category.
- bubonocele
- direct inguinal hernia
- double inguinal hernia
- indirect inguinal hernia
- inguinal hernia NOS
- oblique inguinal hernia
- scrotal hernia
- acquired hernia
- congenital [except diaphragmatic or hiatus] hernia
- recurrent hernia
Applicable To
Conditions this code is used for: synonyms of the title or, for "other specified" codes, the conditions assigned to it. The list is not exhaustive.
- Inguinal hernia with gangrene NOS
- Unilateral inguinal hernia with gangrene NOS
Excludes2
Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.
- certain conditions originating in the perinatal period (P04-P96)
- certain infectious and parasitic diseases (A00-B99)
- complications of pregnancy, childbirth and the puerperium (O00-O9A)
- congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
- endocrine, nutritional and metabolic diseases (E00-E88)
- injury, poisoning and certain other consequences of external causes (S00-T88)
- neoplasms (C00-D49)
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
Notes
General instructions on how these codes are used.
- Hernia with both gangrene and obstruction is classified to hernia with gangrene.
Source: CMS ICD-10-CM Tabular List. How to read instructional notes.
Referenced in Other NotesGuidance
Instructional notes printed at other codes that name K40.40, its category, or a range that includes it.
Excludes1 1
These codes carry an Excludes1 note naming K40.40: they are not reported together with it, unless the two conditions are unrelated.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Clinical InformationClinical
Hernia, Inguinal
an abdominal hernia with an external bulge in the groin region. it can be classified by the location of herniation. indirect inguinal hernias occur through the internal inguinal ring. direct inguinal hernias occur through defects in the abdominal wall (transversalis fascia) in hesselbach's triangle. the former type is commonly seen in children and young adults; the latter in adults.
Patient EducationClinical
Gangrene
Gangrene is the death of tissues in your body. It happens when a part of your body loses its blood supply. Gangrene can happen on the surface of the body, such as on the skin, or inside the body, in muscles or organs. Causes include:
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert K40.40 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About K40.40Overview
What is the ICD-10 code for unilateral inguinal hernia, with gangrene, not specified as recurrent?
The ICD-10-CM code for unilateral inguinal hernia, with gangrene, not specified as recurrent is K40.40 (sometimes written as K4040). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
Is K40.40 (Unilateral inguinal hernia, with gangrene) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report unilateral inguinal hernia, with gangrene, not specified as recurrent on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does K40.40 group to?
When unilateral inguinal hernia, with gangrene, not specified as recurrent is the principal diagnosis on an inpatient stay, it groups to MS-DRG 793, 791, 394, 395, 393, with relative weights from 0.6379 to 4.2192 depending on complications. Higher weights mean higher Medicare reimbursement.
Is K40.40 a CC or MCC?
CMS lists K40.40 as an MCC (major complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it places the inpatient stay in the highest-weighted DRG of its severity family. It does not count when the principal diagnosis is one of the 18 closely related codes in its exclusion list.
What is the ICD-9 equivalent of K40.40?
Under the General Equivalence Mappings, unilateral inguinal hernia, with gangrene, not specified as recurrent converts to ICD-9-CM 550.00 (unilat ing hernia w gang). The mapping is a direct match.
