M86.8X21 – Other osteomyelitis, right upper arm

ICD-10-CM 2027 diagnosis code · Other osteopathies

Billable code New in 2027

ICD-10-CM code M86.8X21

Code: M86.8X21 (claims format: M868X21)
Description: Other osteomyelitis, right upper arm
Billable: Yes – valid for HIPAA-covered transactions
Valid for: Dates of service October 1, 2026 – September 30, 2027 (FY2027)
Chapter: 13. Diseases of the musculoskeletal system and connective tissue (M00-M99)
Block: M86-M90 Other osteopathies
Parent codes: M86 › M86.8 › M86.8X › M86.8X2

Notes inherited from parent codes

Instructional notes at a category or block level apply to every code below it.

M86 – Osteomyelitis

Excludes1 (not coded here):

osteomyelitis due to:
echinococcus (B67.2)
gonococcus (A54.43)
salmonella (A02.24)

Excludes2 (not included here):

ostemyelitis of:
orbit (H05.0-)
petrous bone (H70.2-)
vertebra (M46.2-)

Use additional code:

code (B95-B97) to identify infectious agent
code to identify major osseous defect, if applicable (M89.7-)

M86.8 – Other osteomyelitis

Applicable to:

Brodie's abscess

Block M86-M90

Excludes1 (not coded here):

postprocedural osteopathies (M96.-)

Related codes in M86.8X2

Frequently asked questions

What is ICD-10 code M86.8X21?

M86.8X21 is the ICD-10-CM code for other osteomyelitis, right upper arm, in the block M86-M90 (Other osteopathies).

Is M86.8X21 a billable code?

Yes. M86.8X21 is a billable/specific code that can be used to indicate a diagnosis for reimbursement purposes.

What category does M86.8X21 belong to?

It belongs to category M86 – Osteomyelitis.

Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.