ICD-10-CM 2027 diagnosis code
S31.656AOpen bite of abdominal wall, right flank with penetration into peritoneal cavity, initial encounter
S31.656A is a valid, billable ICD-10-CM code for open bite of abdominal wall, right flank with penetration into peritoneal cavity, initial encounter. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.Short description: Open bite of abd wall, r flank with penet perit cav, init
Code last changed in FY2026 (effective October 1, 2025). Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data
About S31.656A
S31.656A is the ICD-10-CM diagnosis code for open bite of abdominal wall, right flank with penetration into peritoneal cavity, initial encounter. It belongs to category S31 (open wound of abdomen, lower back, pelvis and external genitals), block S30-S39 (injuries to the abdomen, lower back, lumbar spine, pelvis and external genitals) and chapter 19 (injury, poisoning and certain other consequences of external causes). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.
The 7th character "A" means initial encounter: use it while the patient is receiving active treatment for the condition.
As a secondary diagnosis it is an MCC (major complication or comorbidity), which can move an inpatient stay into the highest-paying "with MCC" MS-DRG of its family, unless the principal diagnosis excludes it.
In MS-DRG v44.0, it is part of the grouping logic for DRG 393 (Other Digestive System Diagnoses with MCC, relative weight 1.5881), DRG 394 (Other Digestive System Diagnoses with CC, relative weight 0.9228), DRG 395 (Other Digestive System Diagnoses without CC/MCC, relative weight 0.6382), DRG 963 (Other Multiple Significant Trauma with MCC, relative weight 2.6363), DRG 964 (Other Multiple Significant Trauma with CC, relative weight 1.4972) and DRG 965 (Other Multiple Significant Trauma without CC/MCC, relative weight 1.0059), in MDC 06 (Diseases and Disorders of the Digestive System) and MDC 24 (Multiple Significant Trauma), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
It was added in FY2026, effective October 1, 2025.
7th character
Ainitial encounter
CC/MCC status for this injury by encounter: MCC for A; Neither CC nor MCC for D, S.
Other encounter types for S31.656:
Notes that apply from higher levels
Instructions written at a parent level also apply to S31.656A.
Broader instructions also apply from S30-S39 Injuries to the abdomen, lower back, lumbar spine, pelvis and external genitals and Chapter 19: Injury, poisoning and certain other consequences of external causes.
MS-DRG v44.0 grouping
All DRGs →Inpatient MS-DRGs this diagnosis can group to, as the principal or a secondary diagnosis, depending on the rest of the claim.
MDC 06 · Diseases and Disorders of the Digestive System
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2026 (effective 10/1/2025): Added
- No changes since FY2026.
Common questions about S31.656A
Is S31.656A billable?
- Yes. S31.656A is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
What does the "A" at the end of S31.656A mean?
- It is the 7th character for initial encounter. Per the official guidelines, use it while the patient is receiving active treatment for the condition.
Can S31.656A be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict S31.656A as a principal diagnosis.
Is S31.656A a CC or MCC?
- S31.656A is an MCC (major complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.
What DRG does S31.656A group to?
- S31.656A is used in the MS-DRG v44.0 logic for MS-DRG 393 (Other Digestive System Diagnoses with MCC), MS-DRG 394 (Other Digestive System Diagnoses with CC), MS-DRG 395 (Other Digestive System Diagnoses without CC/MCC), MS-DRG 963 (Other Multiple Significant Trauma with MCC), MS-DRG 964 (Other Multiple Significant Trauma with CC) and MS-DRG 965 (Other Multiple Significant Trauma without CC/MCC). Which one applies depends on whether it is the principal diagnosis and on the rest of the claim.