2026 ICD-10-CM Diagnosis Code S76.309AUnspecified injury of muscle, fascia and tendon of the posterior muscle group at thigh level, unspecified thigh, initial encounter

ICD-10-CM Codes›S00–T88›S70-S79›S76

ICD-10-CM S76.309A
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

S76.309A is a billable ICD-10-CM diagnosis code for unspecified injury of muscle, fascia and tendon of the posterior muscle group at thigh level, unspecified thigh, 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 hamstring injury. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Injury to nerves, muscles and tendons, initial encounter.

Code Identity

ICD-10-CM Code
S76.309A
Billable Status
Yes — Valid for Submission
Code Describes
Unspecified injury of muscle, fascia and tendon of the posterior muscle group at thigh level, unspecified thigh, initial encounter
Short Description
Unsp inj msl/fasc/tnd post grp at thi lev, unsp thigh, init
Parent Code
S76.309
Unspecified injury of muscle, fascia and tendon of the posterior muscle group at thigh level, unspecified thigh

Code Classification

ChapterS00–T88Injury, poisoning and certain other consequences of external causes
SectionS70-S79Injuries to the hip and thigh
CategoryS76Injury of muscle, fascia and tendon at hip and thigh level
This CodeS76.309AUnspecified injury of muscle, fascia and tendon of the posterior muscle group at thigh level, unspecified thigh, initial encounter

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Hamstring injury

Coding GuidelinesGuidance

The appropriate 7th character is to be added to each code from block Injury of muscle, fascia and tendon at hip and thigh level (S76). 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 INJ025
Injury to nerves, muscles and tendons, initial encounter
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Leg Injuries and Disorders

Your legs are made up of bones, blood vessels, muscles, and other connective tissue. They are important for motion and standing. Playing sports, running, falling, or having an accident can damage your legs. Common leg injuries include sprains and strains, joint dislocations, and fractures (broken bones).

Read the full article at MedlinePlus

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

Convert S76.309A to ICD-9-CMHistory

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

ICD-9-CM
959.6 Hip & thigh injury 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 S76.309AOverview

Is S76.309A a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report unspecified injury of muscle, fascia and tendon of the posterior muscle group at thigh level, unspecified thigh, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What does the 7th character A in S76.309A mean?

The final character A marks the initial encounter: use it while the patient is receiving active treatment for unspecified injury of muscle, fascia and tendon of the posterior muscle group at thigh level, unspecified thigh, such as an emergency visit or first evaluation.

What MS-DRG does S76.309A group to?

When unspecified injury of muscle, fascia and tendon of the posterior muscle group at thigh level, unspecified thigh, 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 S76.309A?

Under the General Equivalence Mappings, unspecified injury of muscle, fascia and tendon of the posterior muscle group at thigh level, unspecified thigh, initial encounter converts to ICD-9-CM 959.6 (hip & thigh injury 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.