2026 ICD-10-CM Diagnosis Code S44.21XDInjury of radial nerve at upper arm level, right arm, subsequent encounter

ICD-10-CM Codes›S00–T88›S40-S49›S44

ICD-10-CM S44.21XD
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

S44.21XD is a billable ICD-10-CM diagnosis code for injury of radial nerve at upper arm level, right arm, subsequent encounter. The 7th character D marks it as a subsequent encounter code, used during routine care in the healing or recovery phase. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 949 through 950. The code is exempt from POA reporting. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Injury to nerves, muscles and tendons, subsequent encounter.

Code Identity

ICD-10-CM Code
S44.21XD
Billable Status
Yes — Valid for Submission
Code Describes
Injury of radial nerve at upper arm level, right arm, subsequent encounter
Short Description
Injury of radial nerve at upper arm level, right arm, subs
Parent Code
S44.21
Injury of radial nerve at upper arm level, right arm

Code Classification

ChapterS00–T88Injury, poisoning and certain other consequences of external causes
SectionS40-S49Injuries to the shoulder and upper arm
CategoryS44Injury of nerves at shoulder and upper arm level
This CodeS44.21XDInjury of radial nerve at upper arm level, right arm, subsequent encounter

Present on Admission (POA)Billing

S44.21XD is exempt from POA reporting on inpatient claims to general acute care hospitals. Review other POA exempt codes.

Coding GuidelinesGuidance

The appropriate 7th character is to be added to each code from block Injury of nerves at shoulder and upper arm level (S44). 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 INJ062
Injury to nerves, muscles and tendons, subsequent encounter
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Peripheral Nerve Disorders

Nerves are like wires that carry messages back and forth between your brain and your body. Your peripheral nerves branch off from your brain and spinal cord and connect to all parts of your body, including your muscles and organs.

The full article covers:

  • What are peripheral nerves?
  • What are peripheral nerve disorders?
  • What causes peripheral nerve disorders?
  • What are the symptoms of peripheral nerve disorders?
  • How are peripheral nerve disorders diagnosed?
  • What are the treatments for peripheral nerve disorders?
  • Can peripheral nerve disorders be prevented?

Read the full article at MedlinePlus

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

Convert S44.21XD to ICD-9-CMHistory

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

ICD-9-CM
V58.89 Other specfied aftercare
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 S44.21XDOverview

Is S44.21XD (Injury of radial nerve at upper arm level, right arm) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report injury of radial nerve at upper arm level, right arm, subsequent encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What does the 7th character D in S44.21XD mean?

The final character D marks a subsequent encounter: use it for routine care while the injury of radial nerve at upper arm level, right arm is healing, after active treatment has ended.

What MS-DRG does S44.21XD group to?

When injury of radial nerve at upper arm level, right arm, subsequent encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 949, 950, with relative weights from 0.6277 to 1.1897 depending on complications. Higher weights mean higher Medicare reimbursement.

Is S44.21XD exempt from POA reporting?

Yes. CMS lists this code among those exempt from present on admission reporting, so hospitals do not assign a POA indicator for injury of radial nerve at upper arm level, right arm, subsequent encounter on inpatient claims.

What is the ICD-9 equivalent of S44.21XD?

Under the General Equivalence Mappings, injury of radial nerve at upper arm level, right arm, subsequent encounter converts to ICD-9-CM V58.89 (other specfied aftercare). 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.