M86.8X21 ICD-10-CM Code: Other osteomyelitis, right upper arm
Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.
Code Set: New for FY2027 — not valid before October 1, 2026.
Code Overview
Official Tabular Instructional Notes
Sequencing, inclusion, and exclusion notes published for M86.8X21 in the official ICD-10-CM tabular list.
Notes without a marker are published on M86.8X21 itself; “inherited from” names the category or block whose note applies here.
Excludes1 — Not Coded Here
Conditions generally not reported together with this code (Excludes1) -- an error unless the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).
- osteomyelitis due to: inherited from M86
- echinococcus (B67.2) inherited from M86Compare M86.8X21 vs B67.2 →
- gonococcus (A54.43) inherited from M86Compare M86.8X21 vs A54.43 →
- salmonella (A02.24) inherited from M86Compare M86.8X21 vs A02.24 →
- postprocedural osteopathies (M96.-) inherited from M86-M90Compare M86.8X21 vs M96 →
Excludes2 — Not Included Here
Conditions not covered by this code, but which may be reported alongside it when both are present.
- ostemyelitis of: inherited from M86
- orbit (H05.0-) inherited from M86Compare M86.8X21 vs H05.0 →
- petrous bone (H70.2-) inherited from M86Compare M86.8X21 vs H70.2 →
- vertebra (M46.2-) inherited from M86Compare M86.8X21 vs M46.2 →
Change history
- Upcoming · effective FY2027 — October 1, 2026Will be added to the code setOther osteomyelitis, right upper armFY2027 changes
Verify Before Coding
- No Medicare Code Editor or MS-DRG Definitions Manual restrictions apply to this code.
From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim in Claim Check.
Relationships & Classification
Other codes that name M86.8X21 or its code family, from the CMS ICD-10-CM tabular instructional notes. Tabular-note edges are stored at the code family level that carries each note.
Referenced by 1 Code First instruction: M89.7 — Major osseous defect (via M86.-).
These codes instruct coders to sequence this condition first when it applies.
Related Codes
Same condition, opposite side
Same category and title, differing only in which side of the body is affected.
M86.8X22 — Other osteomyelitis, left upper arm (left)Compare M86.8X21 vs M86.8X22 →, M86.8X29 — Other osteomyelitis, unspecified upper arm (unspecified)Compare M86.8X21 vs M86.8X29 →
Same Index main term, other category
The ICD-10-CM Index to Diseases and Injuries files this code under the main term “Abscess”; these codes share that main term but sit in a different category of the Tabular List.
M71.01 — Abscess of bursa, shoulder (bursa, shoulder), M71.02 — Abscess of bursa, elbow (bursa, elbow), M71.03 — Abscess of bursa, wrist (bursa, wrist), M71.04 — Abscess of bursa, hand (bursa, hand), M71.05 — Abscess of bursa, hip (bursa, hip), M71.06 — Abscess of bursa, knee (bursa, knee), M71.07 — Abscess of bursa, ankle and foot (bursa, foot), M71.08 — Abscess of bursa, other site (bursa, specified site NEC), M71.09 — Abscess of bursa, multiple sites (bursa, multiple sites), M72.8 — Other fibroblastic disorders (fascia), N13.6 — Pyonephrosis (kidney, with calculus, with hydronephrosis), N15.1 — Renal and perinephric abscess (kidney), N20.0 — Calculus of kidney (kidney, with calculus), N28.89 — Other specified disorders of kidney and ureter (periureteral), N34.0 — Urethral abscess (lacunar), N41.2 — Abscess of prostate (prostate), N45.4 — Abscess of epididymis or testis (testis), N48.21 — Abscess of corpus cavernosum and penis (penis), N49.0 — Inflammatory disorders of seminal vesicle (seminal vesicle), N49.1 — Inflammatory disorders of spermatic cord, tunica vaginalis and vas deferens (vas deferens), +173 more
Contextual Map
Every relationship of M86.8X21 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.
Hierarchy
- M00-M99 — Chapter 13: Diseases of the Musculoskeletal System and Connective Tissue (M00-M99) (M00-M99)[Hierarchy]
- M86-M90 — Other osteopathies[Hierarchy]
Referenced by Code First instructions
- M89.7 — Major osseous defect[Code First](via M86.-): “osteomyelitis (M86.-)” · Check M86.8X21 + M89.7 together
Nearest codes (40)
- M86 — Osteomyelitis[Sibling]
- M86.652 — Other chronic osteomyelitis, left thigh[Sibling]
- M86.659 — Other chronic osteomyelitis, unspecified thigh[Sibling]
- M86.66 — Other chronic osteomyelitis, tibia and fibula[Sibling]
- M86.661 — Other chronic osteomyelitis, right tibia and fibula[Sibling]
- M86.662 — Other chronic osteomyelitis, left tibia and fibula[Sibling]
- M86.669 — Other chronic osteomyelitis, unspecified tibia and fibula[Sibling]
- M86.67 — Other chronic osteomyelitis, ankle and foot[Sibling]
- and 32 more
Change history
- FY2027 — Will be added to the code set[Change history]
Nearest Codes in This Family
Official ICD-10-CM classifications closest to M86.8X21 in its code family, with their registry titles.
- M86.8X1 — Other osteomyelitis, shoulder
- M86.8X11 — Other osteomyelitis, right shoulder
- M86.8X12 — Other osteomyelitis, left shoulder
- M86.8X19 — Other osteomyelitis, unspecified shoulder
- M86.8X2 — Other osteomyelitis, upper arm
- M86.8X22 — Other osteomyelitis, left upper arm
- M86.8X29 — Other osteomyelitis, unspecified upper arm
- M86.8X3 — Other osteomyelitis, forearm
- M86.8X31 — Other osteomyelitis, right forearm
- M86.8X32 — Other osteomyelitis, left forearm