2027 ICD-10-CM Diagnosis Code M89.8X2Other specified disorders of bone, upper arm

ICD-10-CM Codes›M00–M99›M86-M90›M89

ICD-10-CM M89.8X2
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

M89.8X2 is a billable ICD-10-CM diagnosis code for other specified disorders of bone, upper arm. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 564 through 566. Coders also document this condition as enostosis of humerus. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified bone disease and musculoskeletal deformities.

Code Identity

ICD-10-CM Code
M89.8X2
Billable Status
Yes — Valid for Submission
Code Describes
Other specified disorders of bone, upper arm
Short Description
Other specified disorders of bone, upper arm
Same as the full description in the CMS dataset.
Parent Code
M89.8X
Other specified disorders of bone

Code Classification

ChapterM00–M99Diseases of the musculoskeletal system and connective tissue
SectionM86-M90Other osteopathies
CategoryM89Other disorders of bone
This CodeM89.8X2Other specified disorders of bone, upper arm

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Enostosis of humerus
  • Exostosis of bilateral humeri
  • Exostosis of elbow
  • Exostosis of humerus
  • Exostosis of left humerus
  • Exostosis of right humerus
  • Lesion of left upper arm bone
  • Lesion of right upper arm bone

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to M89.8X2: its own notes plus those printed at block M86-M90 and Chapter 13. A note printed at a category, block or chapter applies to every code under it.

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

From Block M86-M90 Other osteopathies applies to 732 codes
  • postprocedural osteopathies (M96.-)

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.

From Chapter 13 (M00-M99) Diseases of the musculoskeletal system and connective tissue applies to 6,687 codes
  • arthropathic psoriasis (L40.5-)
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • compartment syndrome (traumatic) (T79.A-)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)

Notes

General instructions on how these codes are used.

From Chapter 13 (M00-M99) Diseases of the musculoskeletal system and connective tissue applies to 6,687 codes
  • Use an external cause code following the code for the musculoskeletal condition, if applicable, to identify the cause of the musculoskeletal condition

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR MUS028
Other specified bone disease and musculoskeletal deformities
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Bone Diseases

Your bones help you move, give you shape and support your body. They are living tissues that rebuild constantly throughout your life. During childhood and your teens, your body adds new bone faster than it removes old bone. After about age 20, you can lose bone faster than you make bone.

Read the full article at MedlinePlus

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

Convert M89.8X2 to ICD-9-CMHistory

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

ICD-9-CM
733.99 Bone & cartilage dis NEC
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 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About M89.8X2Overview

What is the ICD-10 code for other specified disorders of bone, upper arm?

The ICD-10-CM code for other specified disorders of bone, upper arm is M89.8X2 (sometimes written as M898X2). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is M89.8X2 (Other specified disorders of bone) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report other specified disorders of bone, upper arm on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does M89.8X2 group to?

When other specified disorders of bone, upper arm is the principal diagnosis on an inpatient stay, it groups to MS-DRG 564, 566, 565, with relative weights from 0.7374 to 1.4909 depending on complications. Higher weights mean higher Medicare reimbursement.

Can M89.8X2 be reported with a code from M96?

Not as a rule. The Excludes1 note at block M86-M90, which applies to M89.8X2, lists "postprocedural osteopathies (M96.-)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).

What is the ICD-9 equivalent of M89.8X2?

Under the General Equivalence Mappings, other specified disorders of bone, upper arm converts to ICD-9-CM 733.99 (bone & cartilage dis NEC). The mapping is approximate, so confirm the match fits the documentation.