2026 ICD-10-CM Diagnosis Code R10.8A9Flank tenderness, unspecified
R10.8A9 is a billable ICD-10-CM diagnosis code for flank tenderness, unspecified. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 391 through 392. As a symptom code, it should not be used as a principal diagnosis once a related definitive diagnosis has been established.
Code Identity
Code Classification
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Inclusion Terms
- Flank tenderness NOS
These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
- Tenderness, abdominal - R10.819
- flank - R10.8A9
External Cause of Injuries IndexGuidance
References for this code in the External Cause of Injuries Index.
- Tenderness, abdominal
- flank
Code History & ChangesHistory
New Code R10.8A9 was added to the ICD-10-CM code set for FY 2026, effective October 1, 2025.
Replacement R10.8A9 replaces the following previously assigned code(s):
- R10.84 - Generalized abdominal pain
Questions About R10.8A9Overview
Is R10.8A9 (Flank tenderness) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report flank tenderness, unspecified on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does R10.8A9 group to?
When flank tenderness, unspecified is the principal diagnosis on an inpatient stay, it groups to MS-DRG 391, 392, with relative weights from 0.7796 to 1.2683 depending on complications. Higher weights mean higher Medicare reimbursement.
Can R10.8A9 be a principal diagnosis?
Use it with care. This is a symptom code, so once a definitive diagnosis explaining the flank tenderness, unspecified is established, that condition takes the principal position instead.
