2026 ICD-10-CM Diagnosis Code S99.031GSalter-Harris Type III physeal fracture of right calcaneus, subsequent encounter for fracture with delayed healing

ICD-10-CM CodesS00–T88S90-S99S99

ICD-10-CM S99.031G
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

S99.031G is a billable ICD-10-CM diagnosis code for Salter-Harris Type III physeal fracture of right calcaneus, subsequent encounter for fracture with delayed healing. The 7th character G reports a subsequent encounter for a fracture that is healing more slowly than expected. 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 Fracture of lower limb (except hip), subsequent encounter.

Code Identity

ICD-10-CM Code
S99.031G
Billable Status
Yes — Valid for Submission
Code Describes
Salter-Harris Type III physeal fracture of right calcaneus, subsequent encounter for fracture with delayed healing
Short Description
Salter-Harris Type III physeal fracture of r calcaneus, 7thG
Parent Code
Salter-Harris Type III physeal fracture of right calcaneus

Code Classification

ChapterS00–T88Injury, poisoning and certain other consequences of external causes
SectionS90-S99Injuries to the ankle and foot
CategoryS99Other and unspecified injuries of ankle and foot
This CodeS99.031GSalter-Harris Type III physeal fracture of right calcaneus, subsequent encounter for fracture with delayed healing

Present on Admission (POA)Billing

S99.031G is exempt from POA reporting on inpatient claims to general acute care hospitals. Review other POA exempt codes.

Coding GuidelinesGuidance

The principles of multiple coding of injuries should be followed in coding fractures. Fractures of specified sites are coded individually by site, to the level of detail furnished by medical record content.

A fracture not indicated as open or closed should be coded to closed. A fracture not indicated whether displaced or not displaced should be coded to displaced.

Initial vs. Subsequent Encounter for Fractures

Traumatic fractures are coded using the appropriate 7th character for initial encounter (A, B, C) while the patient is receiving active treatment for the fracture. The appropriate 7th character for initial encounter should also be assigned for a patient who delayed seeking treatment for the fracture or nonunion.

Fractures are coded using the appropriate 7th character for subsequent care for encounters after the patient has completed active treatment of the fracture and is receiving routine care for the fracture during the healing or recovery phase.

Care for complications of surgical treatment for fracture repairs during the healing or recovery phase should be coded with the appropriate complication codes.

Care of complications of fractures, such as malunion and nonunion, should be reported with the appropriate 7th character for subsequent care with nonunion (K, M, N) or subsequent care with malunion (P, Q, R).

The open fracture designations in the assignment of the 7th character for fractures of the forearm, femur and lower leg, including ankle are based on the Gustilo open fracture classification. When the Gustilo classification type is not specified for an open fracture, the 7th character for open fracture type I or II should be assigned (B, E, H, M, Q).

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 INJ042
Fracture of lower limb (except hip), subsequent encounter
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Fractures

A fracture is a break in a bone. Fractures are usually caused by injuries. Since they can sometimes be serious, it's important to get medical care right away if you think you have a fracture.

The full article covers:

  • What is a fracture?
  • What are the different types of fractures?
  • What causes fractures?
  • What are the symptoms of a fracture?
  • How are fractures diagnosed?
  • What are the treatments for fractures?
  • Can fractures be prevented?

Read the full article at MedlinePlus

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

Convert S99.031G to ICD-9-CMHistory

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

ICD-9-CM
V54.16 Aftrcre traum fx low leg
Approximate The match is approximate rather than exact.

Code History & ChangesHistory

Replacement S99.031G replaces the following previously assigned code(s):

  • S92.009G - Unsp fracture of unsp calcaneus, subs for fx w delay heal
FY 2018AddedAdded to the ICD-10-CM code setEffective October 1, 2017.
FY 2019–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About S99.031GOverview

Is S99.031G (Salter-Harris Type III physeal fracture of right calcaneus) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report Salter-Harris Type III physeal fracture of right calcaneus, subsequent encounter for fracture with delayed healing on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What does the 7th character G in S99.031G mean?

The final character G reports a subsequent encounter where the Salter-Harris Type III physeal fracture of right calcaneus is healing more slowly than expected.

What MS-DRG does S99.031G group to?

When Salter-Harris Type III physeal fracture of right calcaneus, subsequent encounter for fracture with delayed healing 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 S99.031G 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 Salter-Harris Type III physeal fracture of right calcaneus, subsequent encounter for fracture with delayed healing on inpatient claims.

What is the ICD-9 equivalent of S99.031G?

Under the General Equivalence Mappings, Salter-Harris Type III physeal fracture of right calcaneus, subsequent encounter for fracture with delayed healing converts to ICD-9-CM V54.16 (aftrcre traum fx low leg). 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.