Skip to content
Dx

ICD-10-CM 2027 diagnosis code

S23.162ASubluxation of T11/T12 thoracic vertebra, initial encounter

✓ Billable / specificRequires 7th character

S23.162A is a valid, billable ICD-10-CM code for subluxation of t11/t12 thoracic vertebra, initial encounter. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.

Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data

About S23.162A

S23.162A is the ICD-10-CM diagnosis code for subluxation of T11/T12 thoracic vertebra, initial encounter. It belongs to category S23 (dislocation and sprain of joints and ligaments of thorax), block S20-S29 (injuries to the thorax) and chapter 19 (injury, poisoning and certain other consequences of external causes). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

The 7th character "A" means initial encounter: use it while the patient is receiving active treatment for the condition.

It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.

In MS-DRG v44.0, it is part of the grouping logic for DRG 551 (Medical Back Problems with MCC, relative weight 1.6358), DRG 552 (Medical Back Problems without MCC, relative weight 0.9584), DRG 963 (Other Multiple Significant Trauma with MCC, relative weight 2.6363), DRG 964 (Other Multiple Significant Trauma with CC, relative weight 1.4972) and DRG 965 (Other Multiple Significant Trauma without CC/MCC, relative weight 1.0059), in MDC 08 (Diseases and Disorders of the Musculoskeletal System and Connective Tissue) and MDC 24 (Multiple Significant Trauma), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Before ICD-10, this condition was coded in ICD-9-CM as 839.21 (closed dislocation, thoracic vertebra).

7th character

Ainitial encounter

Other encounter types for S23.162:

Notes that apply from higher levels

Instructions written at a parent level also apply to S23.162A.

› From S23.1 Subluxation and dislocation of thoracic vertebra
Excludes2
  • fracture of thoracic vertebrae (S22.0-)
Code also
  • any associated:
  • open wound of thorax (S21.-)
  • spinal cord injury (S24.0-, S24.1-)
› From S23 Dislocation and sprain of joints and ligaments of thorax
Includes
  • avulsion of joint or ligament of thorax
  • laceration of cartilage, joint or ligament of thorax
  • sprain of cartilage, joint or ligament of thorax
  • traumatic hemarthrosis of joint or ligament of thorax
  • traumatic rupture of joint or ligament of thorax
  • traumatic subluxation of joint or ligament of thorax
  • traumatic tear of joint or ligament of thorax
Excludes2
  • dislocation, sprain of sternoclavicular joint (S43.2, S43.6)
  • strain of muscle or tendon of thorax (S29.01-)
Code also
  • any associated open wound

Broader instructions also apply from S20-S29 Injuries to the thorax and Chapter 19: Injury, poisoning and certain other consequences of external causes.

MS-DRG v44.0 grouping

All DRGs →

Inpatient MS-DRGs this diagnosis can group to, as the principal or a secondary diagnosis, depending on the rest of the claim.

ICD-9-CM equivalent

Converter →
  • 839.21Closed dislocation, thoracic vertebraapproximate

From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.

Code history

  1. 2016
  2. 2017
  3. 2018
  4. 2019
  5. 2020
  6. 2021
  7. 2022
  8. 2023
  9. 2024
  10. 2025
  11. 2026
  12. 2027
  • FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
  • No changes since FY2016.

Common questions about S23.162A

Is S23.162A billable?

Yes. S23.162A is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).

What does the "A" at the end of S23.162A mean?

It is the 7th character for initial encounter. Per the official guidelines, use it while the patient is receiving active treatment for the condition.

Can S23.162A be used as a principal diagnosis?

Yes. The Medicare Code Editor doesn't restrict S23.162A as a principal diagnosis.

Is S23.162A a CC or MCC?

No. S23.162A is neither a CC nor an MCC under MS-DRG v44.0.

What DRG does S23.162A group to?

S23.162A is used in the MS-DRG v44.0 logic for MS-DRG 551 (Medical Back Problems with MCC), MS-DRG 552 (Medical Back Problems without MCC), MS-DRG 963 (Other Multiple Significant Trauma with MCC), MS-DRG 964 (Other Multiple Significant Trauma with CC) and MS-DRG 965 (Other Multiple Significant Trauma without CC/MCC). Which one applies depends on whether it is the principal diagnosis and on the rest of the claim.

What is the ICD-9 code for S23.162A?

The CMS General Equivalence Mappings map S23.162A to ICD-9-CM 839.21.