2026 ICD-10-CM Diagnosis Code S40.811AAbrasion of right upper arm, initial encounter
S40.811A is a billable ICD-10-CM diagnosis code for abrasion of right upper arm, initial encounter. The 7th character A marks it as an initial encounter code, used while the patient is receiving active treatment. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 604 through 605, 963 through 965. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Superficial injury; contusion, initial encounter.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Abrasion and/or friction burn of shoulder and/or upper arm, infected
- Abrasion and/or friction burn of upper arm with infection
- Abrasion of skin of axilla
- Abrasion of skin of right axilla
- Abrasion of skin of right upper arm
- Abrasion of skin of upper arm
- Infected abrasion of skin of right upper arm
- Infected abrasion of skin of upper arm
- Open wound of right axillary region
- Superficial injury of right upper arm
Coding GuidelinesGuidance
The appropriate 7th character is to be added to each code from block Superficial injury of shoulder and upper arm (S40). Use the following options for the applicable episode of care:
- A - initial encounter
- D - subsequent encounter
- S - sequela
Source: ICD-10-CM Official Guidelines for Coding and Reporting, FY 2026, published by CMS and the National Center for Health Statistics.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Wounds and Injuries
An injury is damage to your body. It is a general term that refers to harm caused by accidents, falls, hits, weapons, and more. In the U.S., millions of people injure themselves every year. These injuries range from minor to life-threatening.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert S40.811A to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About S40.811AOverview
Is S40.811A (Abrasion of right upper arm) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report abrasion of right upper arm, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character A in S40.811A mean?
The final character A marks the initial encounter: use it while the patient is receiving active treatment for abrasion of right upper arm, such as an emergency visit or first evaluation.
What MS-DRG does S40.811A group to?
When abrasion of right upper arm, initial encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 604, 605, 963, 964, 965, with relative weights from 0.9160 to 2.7338 depending on complications. Higher weights mean higher Medicare reimbursement.
What is the ICD-9 equivalent of S40.811A?
Under the General Equivalence Mappings, abrasion of right upper arm, initial encounter converts to ICD-9-CM 912.0 (abrasion shoulder/arm). The mapping is approximate, so confirm the match fits the documentation.
Footnotes
[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.
