2027 ICD-10-CM Diagnosis Code S83.123DPosterior subluxation of proximal end of tibia, unspecified knee, subsequent encounter
S83.123D is a billable ICD-10-CM diagnosis code for posterior subluxation of proximal end of tibia, unspecified knee, 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 2027 (October 1, 2026 through September 30, 2027) 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 Dislocations, subsequent encounter.
Code Identity
Code Classification
Present on Admission (POA)Billing
S83.123D is exempt from POA reporting on inpatient claims to general acute care hospitals. Review the other POA exempt codes in Injuries to the knee and lower leg (S80-S89).
Coding GuidelinesGuidance
The appropriate 7th character is to be added to each code from block Dislocation and sprain of joints and ligaments of knee (S83). 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 2027, published by CMS and the National Center for Health Statistics.
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to S83.123D: its own notes plus those printed at S83.1, S83, block S80-S89, and Chapter 19. A note printed at a category, block or chapter applies to every code under it.
Includes
Further defines, or gives examples of, the content of the category.
- avulsion of joint or ligament of knee
- laceration of cartilage, joint or ligament of knee
- sprain of cartilage, joint or ligament of knee
- traumatic hemarthrosis of joint or ligament of knee
- traumatic rupture of joint or ligament of knee
- traumatic subluxation of joint or ligament of knee
- traumatic tear of joint or ligament of knee
Excludes2
Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.
Use Additional Code
Add a second code, after this one, to fully describe the condition.
- code to identify any retained foreign body, if applicable (Z18.-)
Code Also
A second code may be needed to fully describe the condition; the note gives no sequencing direction.
- any associated open wound
Notes
General instructions on how these codes are used.
- Use secondary code(s) from Chapter 20, External causes of morbidity, to indicate cause of injury. Codes within the T section that include the external cause do not require an additional external cause code
- The chapter uses the S-section for coding different types of injuries related to single body regions and the T-section to cover injuries to unspecified body regions as well as poisoning and certain other consequences of external causes.
7th Character
Every code in the category takes a 7th character from the listed values, with the placeholder X filling any empty positions before it.
- The appropriate 7th character is to be added to each code from category S83
- Ainitial encounter
- Dsubsequent encounter this code
- Ssequela
Source: CMS ICD-10-CM Tabular List. How to read instructional notes.
Referenced in Other NotesGuidance
Instructional notes printed at other codes that name S83.123D, its category, or a range that includes it.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Dislocations
Dislocations are joint injuries that force the ends of your bones out of position. The cause is often a fall or a blow, sometimes from playing a contact sport. You can dislocate your ankles, knees, shoulders, hips, elbows and jaw. You can also dislocate your finger and toe joints.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert S83.123D to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About S83.123DOverview
Is S83.123D a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report posterior subluxation of proximal end of tibia, unspecified knee, subsequent encounter on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What does the 7th character D in S83.123D mean?
The final character D marks a subsequent encounter: use it for routine care while the posterior subluxation of proximal end of tibia, unspecified knee is healing, after active treatment has ended.
What MS-DRG does S83.123D group to?
When posterior subluxation of proximal end of tibia, unspecified knee, subsequent encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 950, 949, with relative weights from 0.7661 to 1.1231 depending on complications. Higher weights mean higher Medicare reimbursement.
Is S83.123D 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 proximal end of tibia, unspecified knee, subsequent encounter on inpatient claims. The code appears in the Injuries to the knee and lower leg (S80-S89) range of the CMS exempt list.
What is the ICD-9 equivalent of S83.123D?
Under the General Equivalence Mappings, posterior subluxation of proximal end of tibia, unspecified knee, subsequent encounter converts to ICD-9-CM V58.89 (other specfied aftercare). The mapping is approximate, so confirm the match fits the documentation.
