2026 ICD-10-CM Diagnosis Code S96.129ALaceration of muscle and tendon of long extensor muscle of toe at ankle and foot level, unspecified foot, initial encounter

ICD-10-CM Codes›S00–T88›S90-S99›S96

ICD-10-CM S96.129A
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

S96.129A is a billable ICD-10-CM diagnosis code for laceration of muscle and tendon of long extensor muscle of toe at ankle and foot level, unspecified foot, 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 564 through 566, 963 through 965. The code is flagged as an unspecified code, since codes identifying laterality exist in the same family. Coders also document this condition as laceration of extensor tendon of foot. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Open wounds to limbs, initial encounter.

Code Identity

ICD-10-CM Code
S96.129A
Billable Status
Yes — Valid for Submission
Code Describes
Laceration of muscle and tendon of long extensor muscle of toe at ankle and foot level, unspecified foot, initial encounter
Short Description
Lacerat msl/tnd lng extn msl toe at ank/ft lev,unsp ft, init
Parent Code
S96.129
Laceration of muscle and tendon of long extensor muscle of toe at ankle and foot level, unspecified foot

Code Classification

ChapterS00–T88Injury, poisoning and certain other consequences of external causes
SectionS90-S99Injuries to the ankle and foot
CategoryS96Injury of muscle and tendon at ankle and foot level
This CodeS96.129ALaceration of muscle and tendon of long extensor muscle of toe at ankle and foot level, unspecified foot, initial encounter

Code EditsBilling

Medicare Code Editor checks that affect claim validity for S96.129A.

Unspecified codes
Unspecified codes exist in the ICD-10-CM classification for circumstances when documentation in the medical record does not provide the level of detail needed to support reporting a more specific code. However, in the inpatient setting, there should generally be very limited and rare circumstances for which the laterality (right, left, bilateral) of a condition is unable to be documented and reported. The following pages contain the list of unspecified ICD-10-CM diagnosis codes for which there is a more specific code to identify laterality (right, left, bilateral) within that code family.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Laceration of extensor tendon of foot
  • Laceration of tendon of foot

Coding GuidelinesGuidance

The appropriate 7th character is to be added to each code from block Injury of muscle and tendon at ankle and foot level (S96). 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 INJ012
Open wounds to limbs, initial encounter
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Foot Injuries and Disorders

Each of your feet has 26 bones, 33 joints, and more than 100 tendons, muscles, and ligaments. No wonder a lot of things can go wrong. Here are a few common problems:

Read the full article at MedlinePlus

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

Convert S96.129A to ICD-9-CMHistory

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

ICD-9-CM
891.2 Opn wnd knee/leg w tendn
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 S96.129AOverview

Is S96.129A a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report laceration of muscle and tendon of long extensor muscle of toe at ankle and foot level, unspecified foot, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What does the 7th character A in S96.129A mean?

The final character A marks the initial encounter: use it while the patient is receiving active treatment for laceration of muscle and tendon of long extensor muscle of toe at ankle and foot level, unspecified foot, such as an emergency visit or first evaluation.

What MS-DRG does S96.129A group to?

When laceration of muscle and tendon of long extensor muscle of toe at ankle and foot level, unspecified foot, initial encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 564, 565, 566, 963, 964, 965, with relative weights from 0.7493 to 2.7338 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of S96.129A?

Under the General Equivalence Mappings, laceration of muscle and tendon of long extensor muscle of toe at ankle and foot level, unspecified foot, initial encounter converts to ICD-9-CM 891.2 (opn wnd knee/leg w tendn). 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.