Name: Chronic multifocal osteomyelitis, multiple sites
Creator: MedCoder.ai

Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.

Coding at a Glance

Tabular directives: 5 Excludes1 · 4 Excludes2 · 2 use-additional codes
Risk adjustment: CMS-HCC V28: 1 category · CMS-HCC V22 category 39

Inpatient Payment Groups (MS-DRG)

Potential MS-DRG participation — not a DRG assignment.

MS-DRGs this diagnosis helps define, as principal or secondary, per the CMS ICD-10-CM/PCS MS-DRG Definitions Manual v43, Appendix B.

MS-DRG 456 — SPINAL FUSION EXCEPT CERVICAL WITH SPINAL CURVATURE, MALIGNANCY, INFECTION OR EXTENSIVE FUSIONS WITH MCC (MDC 08)
MS-DRG 457 — SPINAL FUSION EXCEPT CERVICAL WITH SPINAL CURVATURE, MALIGNANCY, INFECTION OR EXTENSIVE FUSIONS WITH CC (MDC 08)
MS-DRG 458 — SPINAL FUSION EXCEPT CERVICAL WITH SPINAL CURVATURE, MALIGNANCY, INFECTION OR EXTENSIVE FUSIONS WITHOUT CC/MCC (MDC 08)
MS-DRG 539 — OSTEOMYELITIS WITH MCC (MDC 08)
MS-DRG 540 — OSTEOMYELITIS WITH CC (MDC 08)
MS-DRG 541 — OSTEOMYELITIS WITHOUT CC/MCC (MDC 08)

A diagnosis appearing in a group's logic does not by itself determine the DRG assigned to a stay; the grouper uses the full claim.

Risk Adjustment (CMS-HCC)

Payment categories this diagnosis maps to under CMS-HCC V28, payment year 2026.

HCC 92 — Bone/Joint/Muscle/Severe Soft Tissue Infections/Necrosis

Other models: CMS-HCC V22 HCC 39

Risk scores depend on the enrollee's full accepted diagnosis set and segment; a category mapping alone does not determine payment.

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for M86.39 in the official ICD-10-CM tabular list, quoted as published.

Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2026Effective: October 1, 2025

Notes without a marker are published on M86.39 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:
echinococcus (B67.2) inherited from M86Compare M86.39 vs B67.2 →
gonococcus (A54.43) inherited from M86Compare M86.39 vs A54.43 →
salmonella (A02.24) inherited from M86Compare M86.39 vs A02.24 →
postprocedural osteopathies (M96.-) inherited from M86-M90Compare M86.39 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:
orbit (H05.0-) Compare M86.39 vs H05.0 →
petrous bone (H70.2-) Compare M86.39 vs H70.2 →
vertebra (M46.2-) Compare M86.39 vs M46.2 →

Source: inherited from M86

Use Additional Code

Supplementary codes the tabular list directs you to add.

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

Source: inherited from M86

Coder workflow for M86.39

MedCoder structured workflow — derived from this code’s own official record

Before you code M86.39

Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with M86.39. Excludes1 conditions are not reported together with this code unless the record shows they are unrelated (Guidelines I.A.12.a).
See the official tabular notes

Choose the right path

Does the documentation support a condition named in M86.39’s Excludes1 note?
Yes → Do not simply proceed: review the excluded code. Both are reported only when the record shows the two conditions are unrelated.
No → Continue.
ReviewB67.2, A54.43, A02.24, M96

Consider M86.39. Then work the Use Additional Code note, and confirm the code is valid for the date of service in the Verify section.

Documentation check

The provider’s diagnostic statement: Codes are assigned from the provider’s documented diagnosis, not from clinical criteria, test values or a medication list (Guidelines I.A.19).
Acuity: Acute or chronic as documented; when both are documented and separate codes exist, both are reported with the acute code first (Guidelines I.B.8).
The conditions the Use Additional Code note names: Reported with this code when documented; a conditional instruction (“if applicable”, “if known”) applies only when the record supports it.

Official instructions as workflow

Excludes1 — check before selecting M86.39(5 notes)
Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with M86.39: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.
CompareB67.2, A54.43, A02.24, M96
See the official tabular notes · Guidelines I.A.12.a
Excludes2 — not part of M86.39(4 notes)
Coding workflow: The conditions named in this note are not included in M86.39. When the record documents both, both may be reported; the note is a boundary, not a prohibition.
CompareH05.0, H70.2, M46.2
See the official tabular notes · Guidelines I.A.12.b
Use Additional Code — after identifying M86.39(2 notes)
Coding workflow: Check whether the documentation supports the additional code(s) the note names, and report them with M86.39 when it does. Where the instruction is conditional (“if applicable”, “if known”), it applies only when the record documents the condition.
ReviewM89.7
See the official tabular notes · Guidelines I.A.13

Coding decision scenarios

Pattern scenarios for this code’s structure — decision rules, not clinical cases

Documentation: Both the condition M86.39 describes and a condition named in its Excludes1 note are documented for the same encounter.

Coding question: Can both codes be reported?

Path: Review the Excludes1 note and the excluded code, and look for a provider statement on whether the two conditions are related.

Reason: Excludes1 means the two are not coded together; the exception is when the record shows the conditions are unrelated to each other (Guidelines I.A.12.a).

ReviewB67.2, A54.43, A02.24, M96

Documentation: A condition the Use Additional Code note names is documented.

Coding question: Is a second code reported with M86.39?

Path: Review the Use Additional Code note and the code it names.

Reason: The additional code is reported when the record documents the condition; a conditional instruction applies only when its condition is met (Guidelines I.A.13).

ReviewM89.7

Every row is derived from this code’s own record — its title, tabular notes, 7th-character family and same-category siblings — with fixed MedCoder wording; nothing is inferred about a patient. The official notes and guideline text are in the sections each row links to, and they control.

Code Overview

Chronic multifocal osteomyelitis, multiple sites is a billable ICD-10-CM diagnosis code (M86.39).

MedCoder summary Summary composed by MedCoder from this code's official ICD-10-CM record. The tabular instructional notes themselves appear verbatim below.

Indexed Clinical Terms (1)

Official source data — entries quoted as published, in the Index’s own lookup phrasing

Clinical term phrases from the official ICD-10-CM Index to Diseases and Injuries that map to this code. These are alphabetic-index entries shown as the Index writes them — lookup phrasing, not necessarily the wording of a final diagnosis.

Osteomyelitis (general) (infective) (localized) (neonatal) (purulent) (septic) (staphylococcal) (streptococcal) (suppurative) (with periostitis), chronic (or old), hematogenous NEC, multifocal, multiple sites

Don’t confuse M86.39 with…

MedCoder analysis — pairs from this code’s official notes, distinctions written by MedCoder

The codes most likely to be picked instead of M86.39 — named in its own official notes, or sharing its laterality or encounter family — with what separates them and which documentation moves the case. Each links to the full comparison.

B67.2— Excludes1 conflict (Excludes1 — generally not reported together)
Not coded here — the tabular list excludes this pair for the same encounter.
Not reported together with this code, except where the two conditions are documented as unrelated.
What moves you there: Documentation of echinococcus moves the case to B67.2; the two are not reported together unless documented as unrelated.
Full comparison: M86.39 vs B67.2 →
A54.43— Excludes1 conflict (Excludes1 — generally not reported together)
Not coded here — the tabular list excludes this pair for the same encounter.
Not reported together with this code, except where the two conditions are documented as unrelated.
What moves you there: Documentation of gonococcus moves the case to A54.43; the two are not reported together unless documented as unrelated.
Full comparison: M86.39 vs A54.43 →
A02.24— Excludes1 conflict (Excludes1 — generally not reported together)
Not coded here — the tabular list excludes this pair for the same encounter.
Not reported together with this code, except where the two conditions are documented as unrelated.
What moves you there: Documentation of salmonella moves the case to A02.24; the two are not reported together unless documented as unrelated.
Full comparison: M86.39 vs A02.24 →
M96— Excludes1 conflict (Excludes1 — generally not reported together)
Not coded here — the tabular list excludes this pair for the same encounter.
Not reported together with this code, except where the two conditions are documented as unrelated.
What moves you there: Documentation of postprocedural osteopathies moves the case to M96; the two are not reported together unless documented as unrelated.
Full comparison: M86.39 vs M96 →
H05.0— Excludes2 relationship (Informational)
Distinct conditions — both may be reported.
A distinct condition — both may be reported when both are documented.
What moves you there: Documentation of orbit adds H05.0; it is not part of this code and both may be reported when both are documented.
Full comparison: M86.39 vs H05.0 →
H70.2— Excludes2 relationship (Informational)
Distinct conditions — both may be reported.
A distinct condition — both may be reported when both are documented.
What moves you there: Documentation of petrous bone adds H70.2; it is not part of this code and both may be reported when both are documented.
Full comparison: M86.39 vs H70.2 →

Relationships are read from this code's own official notes, its laterality siblings and its encounter family; the wording of each distinction is MedCoder editorial, and the documentation named in each “what moves you there” line is the official note phrase or sibling title itself. Source: CMS ICD-10-CM tabular instructional notes; ICD-10-CM Official Guidelines, Section I.A.12.a.

Decision Points

The directives on this code's own record, as a pre-claim checklist.

2 Use Additional Code instructions — report the named additional code(s) when the documentation supports them. See the Use Additional Code notes
5 Excludes1 entries — codes named there are generally not reported together with this code (Guidelines I.A.12.a). See the Excludes1 notes
4 Excludes2 entries — those conditions are not part of this code and may be reported additionally when documented. See the Excludes2 notes

Checklist rows are derived from this code's own official directives; the wording of each check is MedCoder editorial. The official notes themselves are in the sections each row links to.

Verify Before Coding

CC as a secondary diagnosis (FY2026). Can raise the stay's MS-DRG severity tier.

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

MedCoder structured relationships — computed from published CMS and AHRQ datasets

Other codes that name M86.39 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.-).

Each of these codes carries a Code First note naming this condition — when that code is reported, THIS code is sequenced first, ahead of it.

MS-DRG Grouper Relationships (FY2026)

Potential MS-DRG participation — not a DRG assignment.

FY2026 MS-DRG: CC — Complication or Comorbidity. Reported as a secondary diagnosis, this code raises the stay's MS-DRG severity tier — except when the principal diagnosis is one of 205 clinically related codes on its CMS exclusion list.

Named in the grouper logic of 6 MS-DRGs: DRG 456 (MDC 08), DRG 457 (MDC 08), DRG 458 (MDC 08), DRG 539 (MDC 08), DRG 540 (MDC 08), DRG 541 (MDC 08).

From the CMS MS-DRG Definitions Manual (Appendices B and C). Actual DRG assignment depends on the complete claim.

Clinical classification (AHRQ CCSR):MUS002 — Osteomyelitis (default).

Clinical Classifications Software Refined (CCSR) for ICD-10-CM Diagnoses. Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality.

Related Codes

Same clinical process (MS-DRG)

Acts as CC — raises the severity of other admissions. CMS groups these diagnoses into one MS-DRG principal-diagnosis exclusion process — a CC/MCC on this list never raises severity when the principal diagnosis is also on it.

Same CMS-HCC risk category (V28)

CMS maps these diagnoses to the same Hierarchical Condition Category (Bone/Joint/Muscle/Severe Soft Tissue Infections/Necrosis) for risk-adjusted payment.

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical category (Osteomyelitis).

Same Index main term, other category

The ICD-10-CM Index to Diseases and Injuries files this code under the main term “Osteomyelitis”; these codes share that main term but sit in a different category of the Tabular List.

Contextual Map

Every relationship of M86.39 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.

Run M86.39 with this related code in Claim Check

Hierarchy

M00-M99 — Chapter 13: Diseases of the Musculoskeletal System and Connective Tissue (M00-M99) (M00-M99)[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
M86-M90 — Other osteopathies[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026

Referenced by Code First instructions

M89.7 — Major osseous defect[Code First](via M86.-): “osteomyelitis (M86.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Clinical classification (CCSR)

MUS002 — Osteomyelitis[CCSR]— AHRQ CCSR for ICD-10-CM Diagnoses (HCUP)

Risk adjustment (CMS-HCC)

HCC 92 — Bone/Joint/Muscle/Severe Soft Tissue Infections/Necrosis [CMS-HCC]— CMS-HCC V28 · 2026

MS-DRG Grouper

CC — Complication or Comorbidity [MS-DRG severity]: “As a secondary diagnosis this code can raise the stay's MS-DRG severity tier (CC).”— CMS MS-DRG Definitions Manual (Appendix C) · FY2026
DRG 456 — SPINAL FUSION EXCEPT CERVICAL WITH SPINAL CURVATURE, MALIGNANCY, INFECTION OR EXTENSIVE FUSIONS WITH MCC[MS-DRG]: “SPINAL FUSION EXCEPT CERVICAL WITH SPINAL CURVATURE, MALIGNANCY, INFECTION OR EXTENSIVE FUSIONS WITH MCC (MDC 08)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
DRG 457 — SPINAL FUSION EXCEPT CERVICAL WITH SPINAL CURVATURE, MALIGNANCY, INFECTION OR EXTENSIVE FUSIONS WITH CC[MS-DRG]: “SPINAL FUSION EXCEPT CERVICAL WITH SPINAL CURVATURE, MALIGNANCY, INFECTION OR EXTENSIVE FUSIONS WITH CC (MDC 08)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
DRG 458 — SPINAL FUSION EXCEPT CERVICAL WITH SPINAL CURVATURE, MALIGNANCY, INFECTION OR EXTENSIVE FUSIONS WITHOUT CC/MCC[MS-DRG]: “SPINAL FUSION EXCEPT CERVICAL WITH SPINAL CURVATURE, MALIGNANCY, INFECTION OR EXTENSIVE FUSIONS WITHOUT CC/MCC (MDC 08)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
DRG 539 — OSTEOMYELITIS WITH MCC[MS-DRG]: “OSTEOMYELITIS WITH MCC (MDC 08)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
DRG 540 — OSTEOMYELITIS WITH CC[MS-DRG]: “OSTEOMYELITIS WITH CC (MDC 08)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
DRG 541 — OSTEOMYELITIS WITHOUT CC/MCC[MS-DRG]: “OSTEOMYELITIS WITHOUT CC/MCC (MDC 08)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026

MDC crossing

MDC 08 — Diseases and Disorders of the Musculoskeletal System and Connective Tissue[MDC crossing]: “Diseases and Disorders of the Musculoskeletal System and Connective Tissue — the grouper's crossing between diagnoses and procedures: a principal diagnosis sets the MDC, and same-MDC procedures move the stay to its surgical DRGs. 18,508 same-MDC procedures group here; browse them on the MDC page.”— CMS MS-DRG Definitions Manual · FY2026

Index entries

Osteomyelitis (general) (infective) (localized) (neonatal) (purulent) (septic) (staphylococcal) (streptococcal) (suppurative) (with periostitis), chronic (or old), hematogenous NEC, multifocal, multiple sites[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026

Nearest codes (40)

M86 — Osteomyelitis[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
M86.331 — Chronic multifocal osteomyelitis, right radius and ulna[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
M86.332 — Chronic multifocal osteomyelitis, left radius and ulna[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
M86.339 — Chronic multifocal osteomyelitis, unspecified radius and ulna[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
M86.34 — Chronic multifocal osteomyelitis, hand[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
M86.341 — Chronic multifocal osteomyelitis, right hand[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
M86.342 — Chronic multifocal osteomyelitis, left hand[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
M86.349 — Chronic multifocal osteomyelitis, unspecified hand[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
and 32 more

Change history

FY2016 — In the code set at ICD-10-CM adoption [Change history]— CMS release files (code change ledger) · icd10cm-fy2016

Sources for this page

Codes, titles, notes, index terms and mappings on this page are transcribed from the datasets below. Relationships MedCoder computed and text MedCoder wrote are labelled where they appear.

Code, title, tabular notes and index terms Official source data: CMS/CDC ICD-10-CM FY2026 tabular list, index and tables, effective October 1, 2025 Release, file and checksum · Publisher’s page
Claim edits Official source data: CMS Definitions of Medicare Code Edits — v43.1 (April 2026) Release, file and checksum · Publisher’s page
Inpatient payment groups Official source data: CMS MS-DRG Definitions Manual (incl. Appendix B diagnosis index, Appendix C CC/MCC list, Appendix E procedure index) and IPPS Final Rule tables — v43 Release, file and checksum · Publisher’s page
Risk adjustment Official source data: 2026 Mid-Year Final ICD-10 Mappings + Model Software (cms.gov/files/zip/2026-midyear-final-icd-10-mappings.zip, 2026-midyear-final-model-software.zip) — CMS-HCC V28, PY2026 mid-year final release Release, file and checksum · Publisher’s page
Change history and date-of-service validity Official source data: CMS ICD-10-CM release addenda, ingested release by release into the change ledger Release, file and checksum · Publisher’s page
Comparisons, relationships and the contextual map MedCoder structured relationship: Computed by MedCoder from the tabular notes and tables above; every derived relationship is marked as derived where it appears
Summary and FAQ answers MedCoder explanation: Written by MedCoder to explain the sources above: drafted with AI assistance, checked by a person against the release files, and labelled as MedCoder text where it appears. Not official text.

Labels on this page: Official source data · MedCoder structured relationship · MedCoder explanation. How to read the labels · All data sources and release dates

Cite this page

Reference this page in a research guide, syllabus or article. The release is included because code content changes each year.

MedCoder.ai. "M86.39 — Chronic multifocal osteomyelitis, multiple sites." ICD-10-CM FY2026. https://medcoder.ai/icd10/code/m86.39-chronic-multifocal-osteomyelitis-multiple-sites

Change history

FY2016 — October 1, 2015
In the code set at ICD-10-CM adoption
Chronic multifocal osteomyelitis, multiple sites

No changes since FY2016 — additions, deletions, description changes and billable-status changes are tracked through FY2027 (effective October 1, 2026), and none are recorded for this code. Note changes are tracked from FY2027 only.

Nearest Codes in This Family

Official ICD-10-CM classifications closest to M86.39 in its code family, with their registry titles.

View all codes in the M86 family

M86.39 ICD-10-CM Code: Chronic multifocal osteomyelitis, multiple sites

Coding at a Glance

Inpatient Payment Groups (MS-DRG)

Risk Adjustment (CMS-HCC)

Coding instructions

Excludes1 — Not Coded Here

Excludes2 — Not Included Here

Use Additional Code

Coder workflow for M86.39

Before you code M86.39

Choose the right path

Documentation check

Official instructions as workflow

Coding decision scenarios

Code Overview

Indexed Clinical Terms (1)

Don’t confuse M86.39 with…

Decision Points

Verify Before Coding

Relationships & Classification

MS-DRG Grouper Relationships (FY2026)

Related Codes

Same clinical process (MS-DRG)

Same CMS-HCC risk category (V28)

Same clinical category (CCSR)

Same Index main term, other category

Contextual Map

Hierarchy

Referenced by Code First instructions

Clinical classification (CCSR)

Risk adjustment (CMS-HCC)

MS-DRG Grouper

MDC crossing

Index entries

Nearest codes (40)

Change history

Sources for this page

Cite this page

Change history

Nearest Codes in This Family