2026 ICD-10-CM Diagnosis Code S59.902AUnspecified injury of left elbow, initial encounter

ICD-10-CM Codes›S00–T88›S50-S59›S59

ICD-10-CM S59.902A
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

S59.902A is a billable ICD-10-CM diagnosis code for unspecified injury of left elbow, 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 913 through 914, 963 through 965. Coders also document this condition as injury of left elbow region. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other unspecified injury.

Code Identity

ICD-10-CM Code
S59.902A
Billable Status
Yes — Valid for Submission
Code Describes
Unspecified injury of left elbow, initial encounter
Short Description
Unspecified injury of left elbow, initial encounter
Same as the full description in the CMS dataset.
Parent Code
S59.902
Unspecified injury of left elbow

Code Classification

ChapterS00–T88Injury, poisoning and certain other consequences of external causes
SectionS50-S59Injuries to the elbow and forearm
CategoryS59Other and unspecified injuries of elbow and forearm
This CodeS59.902AUnspecified injury of left elbow, initial encounter

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Injury of left elbow region

Coding GuidelinesGuidance

The appropriate 7th character is to be added to each code from block Other and unspecified injuries of elbow and forearm (S59). 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.

CCSR INJ027
Other unspecified injury
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Elbow Injuries and Disorders

Your elbow joint is made up of bone, cartilage, ligaments and fluid. Muscles and tendons help the elbow joint move. When any of these structures is hurt or diseased, you have elbow problems.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert S59.902A to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
959.3 Elb/forearm/wrst inj NOS
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About S59.902AOverview

Is S59.902A (Unspecified injury of left elbow) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report unspecified injury of left elbow, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What does the 7th character A in S59.902A mean?

The final character A marks the initial encounter: use it while the patient is receiving active treatment for unspecified injury of left elbow, such as an emergency visit or first evaluation.

What MS-DRG does S59.902A group to?

When unspecified injury of left elbow, initial encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 913, 914, 963, 964, 965, with relative weights from 0.8855 to 2.7338 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of S59.902A?

Under the General Equivalence Mappings, unspecified injury of left elbow, initial encounter converts to ICD-9-CM 959.3 (elb/forearm/wrst inj NOS). 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.