2026 ICD-10-CM Diagnosis Code S54.20XAInjury of radial nerve at forearm level, unspecified arm, initial encounter
S54.20XA is a billable ICD-10-CM diagnosis code for injury of radial nerve at forearm level, unspecified 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 963 through 965. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Injury to nerves, muscles and tendons, initial encounter.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Closed injury of radial nerve
- Closed injury of sensory branch of radial nerve
- Injury of branch of radial nerve
- Injury of nerve at forearm level
- Injury of radial nerve
- Injury of radial nerve at forearm level
- Lesion of sensory branch of radial nerve
- Open injury of radial nerve
- Open injury of sensory branch of radial nerve
Coding GuidelinesGuidance
The appropriate 7th character is to be added to each code from block Injury of nerves at forearm level (S54). 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
Arm Injuries and Disorders
Of the 206 bones in your body, three of them are in your arm: the humerus, radius, and ulna. Your arms are also made up of muscles, joints, tendons, and other connective tissue. Injuries to any of these parts of the arm can occur during sports, a fall, or an accident.
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Convert S54.20XA to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About S54.20XAOverview
Is S54.20XA (Injury of radial nerve at forearm level, unspecified arm) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report injury of radial nerve at forearm level, unspecified arm, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character A in S54.20XA mean?
The final character A marks the initial encounter: use it while the patient is receiving active treatment for injury of radial nerve at forearm level, unspecified arm, such as an emergency visit or first evaluation.
What MS-DRG does S54.20XA group to?
When injury of radial nerve at forearm level, unspecified arm, initial encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 963, 964, 965, with relative weights from 0.9405 to 2.7338 depending on complications. Higher weights mean higher Medicare reimbursement.
What is the ICD-9 equivalent of S54.20XA?
Under the General Equivalence Mappings, injury of radial nerve at forearm level, unspecified arm, initial encounter converts to ICD-9-CM 955.3 (injury radial nerve). 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.
