2027 ICD-10-CM Diagnosis Code K40.31Unilateral inguinal hernia, with obstruction, without gangrene, recurrent
ICD-10-CM Codes›K00–K95›K40-K46›K40
- Billable — Valid for Submission
- CC — Complication or Comorbidity
- Not Chronic
K40.31 is a billable ICD-10-CM diagnosis code for unilateral inguinal hernia, with obstruction, without gangrene, 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. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 18 closely related codes. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Abdominal hernia and Intestinal obstruction and ileus.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Intestinal obstruction due to recurrent irreducible inguinal hernia
- Irreducible inguinal hernia
- Irreducible left inguinal hernia
- Irreducible right inguinal hernia
- Obstructed left inguinal hernia
- Obstructed recurrent hernia of anterior abdominal wall
- Obstructed recurrent inguinal hernia
- Obstructed recurrent left inguinal hernia
- Obstructed recurrent right inguinal hernia
- Obstructed right inguinal hernia
- Recurrent inguinal hernia with obstruction
- Recurrent irreducible inguinal hernia with obstruction
- Recurrent irreducible left inguinal hernia
- Recurrent irreducible right inguinal hernia
- Recurrent left inguinal hernia
- Recurrent right inguinal hernia
- Secondary hernia of abdomen
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to K40.31: 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
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 K40.31, its category, or a range that includes it.
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
Hernia
A hernia happens when part of an internal organ or tissue bulges through a weak area of muscle. Most hernias are in the abdomen.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert K40.31 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About K40.31Overview
Is K40.31 a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report unilateral inguinal hernia, with obstruction, without gangrene, recurrent on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does K40.31 group to?
When unilateral inguinal hernia, with obstruction, without gangrene, recurrent is the principal diagnosis on an inpatient stay, it groups to MS-DRG 394, 395, 393, with relative weights from 0.6379 to 1.5877 depending on complications. Higher weights mean higher Medicare reimbursement.
Is K40.31 a CC or MCC?
CMS lists K40.31 as a CC (complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within 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 K40.31?
Under the General Equivalence Mappings, unilateral inguinal hernia, with obstruction, without gangrene, recurrent converts to ICD-9-CM 550.11 (recur unil ing hern-obst). The mapping is a direct match.
