2026 ICD-10-CM Diagnosis Code S43.021DPosterior subluxation of right humerus, subsequent encounter

ICD-10-CM Codes›S00–T88›S40-S49›S43

ICD-10-CM S43.021D
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

S43.021D is a billable ICD-10-CM diagnosis code for posterior subluxation of right humerus, 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. Coders also document this condition as posterior dislocation of shoulder joint. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Dislocations, subsequent encounter.

Code Identity

ICD-10-CM Code
S43.021D
Billable Status
Yes — Valid for Submission
Code Describes
Posterior subluxation of right humerus, subsequent encounter
Short Description
Posterior subluxation of right humerus, subsequent encounter
Same as the full description in the CMS dataset.
Parent Code
S43.021
Posterior subluxation of right humerus

Code Classification

ChapterS00–T88Injury, poisoning and certain other consequences of external causes
SectionS40-S49Injuries to the shoulder and upper arm
CategoryS43Dislocation and sprain of joints and ligaments of shoulder girdle
This CodeS43.021DPosterior subluxation of right humerus, subsequent encounter

Present on Admission (POA)Billing

S43.021D is exempt from POA reporting on inpatient claims to general acute care hospitals. Review other POA exempt codes.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Posterior dislocation of shoulder joint
  • Posterior subluxation of right shoulder
  • Right shoulder subluxation

Coding GuidelinesGuidance

The appropriate 7th character is to be added to each code from block Dislocation and sprain of joints and ligaments of shoulder girdle (S43). 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 INJ044
Dislocations, subsequent encounter
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Dislocated Shoulder

Your shoulder joint is made up of three bones: your collarbone, your shoulder blade, and your upper arm bone. The top of your upper arm bone is shaped like a ball. This ball fits into a cuplike socket in your shoulder blade. A shoulder dislocation is an injury that happens when the ball pops out of your socket.

The full article covers:

  • What is a dislocated shoulder?
  • What causes a dislocated shoulder?
  • Who is at risk for a dislocated shoulder?
  • What are the symptoms of a dislocated shoulder?
  • How is a dislocated shoulder diagnosed?
  • What are the treatments for a dislocated shoulder?

Read the full article at MedlinePlus

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

Convert S43.021D 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 S43.021DOverview

Is S43.021D (Posterior subluxation of right humerus) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report posterior subluxation of right humerus, subsequent encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What does the 7th character D in S43.021D mean?

The final character D marks a subsequent encounter: use it for routine care while the posterior subluxation of right humerus is healing, after active treatment has ended.

What MS-DRG does S43.021D group to?

When posterior subluxation of right humerus, 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 S43.021D 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 posterior subluxation of right humerus, subsequent encounter on inpatient claims.

What is the ICD-9 equivalent of S43.021D?

Under the General Equivalence Mappings, posterior subluxation of right humerus, 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.