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M84.479 ICD-10-CM Code: Pathological fracture, unspecified toe(s)

Billing Status: NO. This is a clinician non-billable / parent hierarchy grouping in the ICD-10-CM system.

Coding at a Glance

7th character
Required — see the character table on this page
Tabular directives
6 Excludes1 · 2 Excludes2

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for M84.479 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 M84.479 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).

Source: inherited from M84.4

Excludes2 — Not Included Here

Conditions not covered by this code, but which may be reported alongside it when both are present.

7th Character Guide

"The appropriate 7th character is to be added to each code from subcategory M84.4:"

  • A — initial encounter for fracture
  • D — subsequent encounter for fracture with routine healing
  • G — subsequent encounter for fracture with delayed healing
  • K — subsequent encounter for fracture with nonunion
  • P — subsequent encounter for fracture with malunion
  • S — sequela

How the encounter character is assigned. “Initial encounter” means the patient is receiving active treatment for the condition — it is not limited to the first visit, and a different or new provider giving active treatment still assigns it. “Subsequent encounter” covers care during the healing or recovery phase after active treatment. “Sequela” is for complications or conditions that arise as a direct result of the original condition.

ICD-10-CM Official Guidelines for Coding and Reporting, Section I.C.19.a (paraphrased by MedCoder).

Variant codes in this family

M84.479A, M84.479D, M84.479G, M84.479K, M84.479P, M84.479S

Character meanings are CMS's official 7th-character extensions for this family, as carried in each variant code's official description; variant codes are registry rows. The explanation of how the encounter character is assigned is MedCoder editorial, distinct from the official content above it.

Coder workflow for M84.479

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

Before you code M84.479

  1. M84.479 is not reportable as written. Select the more specific code beneath it that the documentation supports. Codes are reported to the highest level of specificity the classification provides (Guidelines I.B.2).

    ReviewM84.479A, M84.479D, M84.479G, M84.479K, M84.479P, M84.479S

    See the relationships section · Guide: How to choose an ICD-10-CM code →

  2. Unspecified does not mean incorrect. When the record gives no greater specificity, M84.479 may be the appropriate code. Check the record for detail that supports a more specific sibling. An unspecified code is for records that do not provide the detail a more specific code needs; a query, not an assumption, is the route to specificity (Guidelines I.A.9.b, I.B.18).

    ReviewM84.477, M84.478

    See the relationships section · Guide: Other vs unspecified (NEC vs NOS) →

  3. A 7th character is required in this family. Confirm the documented encounter: initial (active treatment), subsequent (healing or recovery phase), or sequela. M84.479 is not valid without one. “Initial” means active treatment, not the first visit (Guidelines I.C.19.a).

    See the 7th Character Guide · Guide: 7th characters: initial, subsequent, sequela →

  4. Laterality is coded in this family. Confirm the side documented — right, left, or bilateral — and select the matching code (this page’s code: unspecified). The unspecified-side code applies only when the record states no side. Laterality is assigned from the documented side; where a bilateral code exists and both sides are documented, it is used instead of two unilateral codes (Guidelines I.B.13).

    ReviewM84.477 · right, M84.478 · left

    Guide: Laterality coding →

  5. Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with M84.479. 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

  1. Does the documentation support one of the more specific codes beneath M84.479?
    Yes → Select that code and continue the checks below on its own page.
    No → M84.479 cannot be reported as written; query for the specificity its subcategory needs.

    ReviewM84.479A, M84.479D, M84.479G, M84.479K, M84.479P, M84.479S

  2. Does the record document the detail a more specific sibling code needs?
    Yes → Review the specific siblings in this subcategory.
    No → Continue — M84.479 is appropriate when the documentation goes no further.

    ReviewM84.477, M84.478

  3. Does the documentation support a condition named in M84.479’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.

    ReviewM48.5, M84.5, M80, M84.6, M84.3, S12

  4. Is the side documented?
    Yes → Select the code for the documented side (or the bilateral code when both sides are documented and one exists).
    No → Use the unspecified-side code only when the record states no side; a query is the alternative.

    ReviewM84.477 · right, M84.478 · left

  5. Is the encounter phase documented — active treatment, healing or recovery, or a sequela?
    Yes → Assign the matching 7th character; the variant codes are in the 7th Character Guide.
    No → The code is invalid without its 7th character — query for the missing element.

Consider M84.479. Then 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).
Laterality
Right, left or bilateral as documented; unspecified only when the record states no side (Guidelines I.B.13).
Encounter type
Active treatment, healing or recovery phase, or sequela — the basis of the 7th character (Guidelines I.C.19.a).
Open or closed; displaced or nondisplaced
Defaults apply when the record is silent: closed, and displaced (Guidelines I.C.19.c).
Any detail beyond this code’s title
What the record states that a more specific sibling code would capture — or its absence, which itself supports the unspecified code.

Official instructions as workflow

  • Excludes1 — check before selecting M84.479(6 notes)

    Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with M84.479: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.

    CompareM48.5, M84.5, M80, M84.6, M84.3, S12

    See the official tabular notes · Guidelines I.A.12.a

  • Excludes2 — not part of M84.479(2 notes)

    Coding workflow: The conditions named in this note are not included in M84.479. When the record documents both, both may be reported; the note is a boundary, not a prohibition.

    CompareZ87.311

    See the official tabular notes · Guidelines I.A.12.b

Coding decision scenarios

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

Documentation: The provider documents the condition in the terms of this code’s title and records no further detail.

Coding question: Is a more specific sibling code supportable?

Path: Review the specific siblings in this subcategory and what each requires the record to state.

Reason: A more specific code needs documentation of the distinguishing element; without it the unspecified code is appropriate, and a provider query is the route to specificity (Guidelines I.A.9.b, I.B.18).

ReviewM84.477, M84.478

Documentation: Both the condition M84.479 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).

ReviewM48.5, M84.5, M80, M84.6, M84.3, S12

Documentation: The patient returns during the healing or recovery phase after active treatment of the same condition.

Coding question: Which 7th character applies?

Path: Review the official 7th-character definitions for this family in the 7th Character Guide.

Reason: “Initial encounter” means active treatment, not the first visit; care during recovery takes “subsequent encounter”, and a complication arising from the original condition takes “sequela” (Guidelines I.C.19.a).

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

Pathological fracture, unspecified toe(s) is a non-billable ICD-10-CM category code (M84.479). A more specific billable subcode must be selected for claims submission.

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

Decision Points

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

  1. A 7th character applies in this family. Confirm the documented encounter matches the character assigned. See the official 7th-character definitions and this code’s variants
  2. 6 Excludes1 entries — codes named there are generally not reported together with this code (Guidelines I.A.12.a). See the Excludes1 notes
  3. 2 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

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 M84.479 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 2 Excludes1 notes: M48.4 — Fatigue fracture of vertebra (via M84.4.-), M48.5 — Collapsed vertebra, not elsewhere classified (via M84.4.-).

These codes’ tabular lists mark this diagnosis as mutually exclusive — not reported together unless the conditions are documented as unrelated.

Related Codes

Same condition, opposite side

Same category and title, differing only in which side of the body is affected.

M84.477 — Pathological fracture, right toe(s) (right)Compare M84.479 vs M84.477 →, M84.478 — Pathological fracture, left toe(s) (left)Compare M84.479 vs M84.478 →

Same Index main term, other category

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

K08.530 — Fractured dental restorative material without loss of material (restorative material, without loss of material), K08.531 — Fractured dental restorative material with loss of material (restorative material, with loss of material), K08.539 — Fractured dental restorative material, unspecified (restorative material), M27.63 — Post-osseointegration mechanical failure of dental implant (dental implant), M48.50 — Collapsed vertebra, not elsewhere classified, site unspecified (compression), M80.00 — Age-related osteoporosis with current pathological fracture, unspecified site (due to, osteoporosis), M97.0 — Periprosthetic fracture around internal prosthetic hip joint (periprosthetic, hip), M97.1 — Periprosthetic fracture around internal prosthetic knee joint (periprosthetic, knee), M97.2 — Periprosthetic fracture around internal prosthetic ankle joint (periprosthetic, ankle), M97.3 — Periprosthetic fracture around internal prosthetic shoulder joint (periprosthetic, shoulder), M97.4 — Periprosthetic fracture around internal prosthetic elbow joint (periprosthetic, elbow), M97.8 — Periprosthetic fracture around other internal prosthetic joint (periprosthetic, finger), M97.9 — Periprosthetic fracture around unspecified internal prosthetic joint (periprosthetic)

Contextual Map

Every relationship of M84.479 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 M84.479 with these 2 related codes in Claim Check

Hierarchy

Referenced by Excludes1 notes

Nearest codes (40)

Change history

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

Common coding questions

Can M84.479 be billed directly?

No. M84.479 (Pathological fracture, unspecified toe(s)) is a non-billable ICD-10-CM category code. A more specific billable subcode must be selected based on clinical documentation.

Does M84.479 require a 7th character?

Yes. The appropriate 7th character is to be added to each code from subcategory M84.4:.

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
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. "M84.479 — Pathological fracture, unspecified toe(s)." ICD-10-CM FY2026. https://medcoder.ai/icd10/code/m84.479-pathological-fracture-unspecified-toes

Change history

  • FY2016 — October 1, 2015
    In the code set at ICD-10-CM adoption
    Pathological fracture, unspecified toe(s)

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 M84.479 in its code family, with their registry titles.

View all codes in the M84 family