ICD-10-CM 2027
ICD-10 code for flank tenderness
From the official ICD-10-CM alphabetic index entry “Tenderness, abdominal › flank”. Page updated September 29, 2026.
About coding flank tenderness
The ICD-10-CM code for flank tenderness is R10.8A9 (Flank tenderness, unspecified). The official index lists 2 more specific codes, so check the documentation for details such as type, cause, site or severity before settling on R10.8A9.
Within R10.8A, choose R10.8A9 (unspecified) only when documentation doesn't support a more specific option: right flank tenderness (R10.8A1), left flank tenderness (R10.8A2) and suprapubic tenderness (R10.8A3).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 391 (Esophagitis, Gastroenteritis and Miscellaneous Digestive Disorders with MCC, relative weight 1.2392) and DRG 392 (Esophagitis, Gastroenteritis and Miscellaneous Digestive Disorders without MCC, relative weight 0.7645), in MDC 06 (Diseases and Disorders of the Digestive System), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
More specific flank tenderness codes (official index)
Common questions about flank tenderness ICD-10 codes
What is the ICD-10 code for flank tenderness?
- R10.8A9 — Flank tenderness, unspecified. More specific codes apply when the documentation supports them: R10.8A2, R10.8A1.
What is the ICD-10 code for left flank tenderness?
- R10.8A2 — Left flank tenderness.
What is the ICD-10 code for right flank tenderness?
- R10.8A1 — Right flank tenderness.
Is R10.8A9 billable?
- Yes. R10.8A9 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can R10.8A9 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict R10.8A9 as a principal diagnosis.
Is R10.8A9 a CC or MCC?
- No. R10.8A9 is neither a CC nor an MCC under MS-DRG v44.0.