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ICD-10-CM 2027 diagnosis code

M84.331SStress fracture, right ulna, sequela

✓ Billable / specificRequires 7th character

M84.331S is a valid, billable ICD-10-CM code for stress fracture, right ulna, sequela. 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 M84.331S

M84.331S is the ICD-10-CM diagnosis code for stress fracture, right ulna, sequela. It belongs to category M84 (disorder of continuity of bone), block M80-M85 (disorders of bone density and structure) and chapter 13 (diseases of the musculoskeletal system and connective tissue). 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 "S" means sequela: use it for complications or conditions that arise as a direct result of the original 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 559 (Aftercare, Musculoskeletal System and Connective Tissue with MCC, relative weight 1.8088), DRG 560 (Aftercare, Musculoskeletal System and Connective Tissue with CC, relative weight 1.1238) and DRG 561 (Aftercare, Musculoskeletal System and Connective Tissue without CC/MCC, relative weight 0.8258), in MDC 08 (Diseases and Disorders of the Musculoskeletal System and Connective Tissue), 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 905.2 (late effect of fracture of upper extremities).

7th character

Ssequela

CC/MCC status for this injury by encounter: Neither CC nor MCC for A, D, G, S; CC for K, P.

Other encounter types for M84.331:

Notes that apply from higher levels

Instructions written at a parent level also apply to M84.331S.

› From M84.3 Stress fracture
Excludes1
Excludes2
  • personal history of (healed) stress (fatigue) fracture (Z87.312)
  • stress fracture of vertebra (M48.4-)
Use additional code
  • external cause code(s) to identify the cause of the stress fracture
› From M84 Disorder of continuity of bone
Excludes2
  • traumatic fracture of bone-see fracture, by site

Broader instructions also apply from Chapter 13: Diseases of the musculoskeletal system and connective tissue.

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 →
  • 905.2Late effect of fracture of upper extremitiesapproximate

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 M84.331S

Is M84.331S billable?

Yes. M84.331S is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).

What does the "S" at the end of M84.331S mean?

It is the 7th character for sequela. Per the official guidelines, use it for complications or conditions that arise as a direct result of the original condition.

Can M84.331S be used as a principal diagnosis?

Yes. The Medicare Code Editor doesn't restrict M84.331S as a principal diagnosis.

Is M84.331S a CC or MCC?

No. M84.331S is neither a CC nor an MCC under MS-DRG v44.0.

What DRG does M84.331S group to?

M84.331S is used in the MS-DRG v44.0 logic for MS-DRG 559 (Aftercare, Musculoskeletal System and Connective Tissue with MCC), MS-DRG 560 (Aftercare, Musculoskeletal System and Connective Tissue with CC) and MS-DRG 561 (Aftercare, Musculoskeletal System and Connective Tissue 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 M84.331S?

The CMS General Equivalence Mappings map M84.331S to ICD-9-CM 905.2.