M84.532A ICD-10-CM Code: Pathological fracture in neoplastic disease, left ulna, initial encounter for fracture

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for M84.532A in the official ICD-10-CM tabular list, quoted as published.

Notes without a marker are published on M84.532A itself; “inherited from” names the category or block whose note applies here.

7th Character Guide

"The appropriate 7th character is to be added to each code from subcategory M84.5:"

• A — initial encounter for fracture (this page’s code)
• 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

M84.532A, M84.532D, M84.532G, M84.532K, M84.532P, M84.532S

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 M84.532A

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

Before you code M84.532A

1. A 7th character is required in this family. Confirm the documented encounter: initial (active treatment), subsequent (healing or recovery phase), or sequela. This page’s code carries “A”. “Initial” means active treatment, not the first visit (Guidelines I.C.19.a).

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

2. Laterality is coded in this family. Confirm the side documented — right, left, or bilateral — and select the matching code (this page’s code: left). 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).

   ReviewM84.531A · right

   Guide: Laterality coding →

Choose the right path

1. 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.

   ReviewM84.531A · right

2. 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 M84.532A. Then review the Code Also 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).

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).

Official instructions as workflow

• Excludes2 — not part of M84.532A(1 note)

  Coding workflow: The conditions named in this note are not included in M84.532A. When the record documents both, both may be reported; the note is a boundary, not a prohibition.

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

• Code Also — related condition(1 note)

  Coding workflow: Review the related condition when both are documented and the instruction applies. A Code Also note does not fix sequencing; the order follows the circumstances of the encounter.

  See the official tabular notes · Guidelines I.A.17

Coding decision scenarios

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

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.

Official Coding Guidelines

Official source data — quoted verbatim from the CMS/NCHS Official Guidelines

Official source data — quoted verbatim from the CMS/NCHS Official Guidelines

Verbatim excerpts from the ICD-10-CM Official Guidelines for Coding and Reporting (CMS/NCHS) that govern this code.

Don’t confuse M84.532A with…

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

The codes most likely to be picked instead of M84.532A — 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.

• M84.531A— Laterality relationship (Review)

  Same condition; these differ only in which side is documented.

  The same condition on the other side; the documented side decides, and a bilateral code, where one exists, replaces the pair when both sides are documented.

  What moves you there: A documented right side moves the case to M84.531A.

  Full comparison: M84.532A vs M84.531A →

• M84.532D— Encounter relationship (Review)

  Same underlying diagnosis, different encounter phase.

  The same diagnosis at a different phase of care; one encounter takes one 7th character.

  What moves you there: Documentation of a subsequent encounter for fracture with routine healing moves the case to M84.532D.

  Full comparison: M84.532A vs M84.532D →

• M84.532G— Encounter relationship (Review)

  Same underlying diagnosis, different encounter phase.

  The same diagnosis at a different phase of care; one encounter takes one 7th character.

  What moves you there: Documentation of a subsequent encounter for fracture with delayed healing moves the case to M84.532G.

  Full comparison: M84.532A vs M84.532G →

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.

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. Laterality is coded in this family. Confirm the documented side matches the code — the opposite-side siblings are in the relationships section. See the opposite-side sibling codes
3. 1 Code Also note — a second code may apply; the guidelines leave its sequencing to the circumstances of the encounter. See the Code Also notes
4. 1 Excludes2 entry — 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 M84.532A 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 Excludes1 note: M84.4 — Pathological fracture, not elsewhere classified (via M84.5.-).

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

MS-DRG Grouper Relationships (FY2026)

Potential MS-DRG participation — not a DRG assignment.

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 214 clinically related codes on its CMS exclusion list.

Named in the grouper logic of 5 MS-DRGs: DRG 542 (MDC 08), DRG 543 (MDC 08), DRG 544 (MDC 08), DRG 791 (MDC 15), DRG 793 (MDC 15).

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

Clinical classification (AHRQ CCSR):MUS014 — Pathological fracture, initial encounter (default); NEO074 — Conditions due to neoplasm or the treatment of neoplasm.

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.

M84.479A — Pathological fracture, unspecified toe(s), initial encounter for fracture, M84.48XA — Pathological fracture, other site, initial encounter for fracture, M84.50XA — Pathological fracture in neoplastic disease, unspecified site, initial encounter for fracture, M84.511A — Pathological fracture in neoplastic disease, right shoulder, initial encounter for fracture, M84.512A — Pathological fracture in neoplastic disease, left shoulder, initial encounter for fracture, M84.519A — Pathological fracture in neoplastic disease, unspecified shoulder, initial encounter for fracture, M84.521A — Pathological fracture in neoplastic disease, right humerus, initial encounter for fracture, M84.522A — Pathological fracture in neoplastic disease, left humerus, initial encounter for fracture, M84.529A — Pathological fracture in neoplastic disease, unspecified humerus, initial encounter for fracture, M84.531A — Pathological fracture in neoplastic disease, right ulna, initial encounter for fracture, M84.533A — Pathological fracture in neoplastic disease, right radius, initial encounter for fracture, M84.534A — Pathological fracture in neoplastic disease, left radius, initial encounter for fracture, M84.539A — Pathological fracture in neoplastic disease, unspecified ulna and radius, initial encounter for fracture, M84.541A — Pathological fracture in neoplastic disease, right hand, initial encounter for fracture, M84.542A — Pathological fracture in neoplastic disease, left hand, initial encounter for fracture, M84.549A — Pathological fracture in neoplastic disease, unspecified hand, initial encounter for fracture, M84.550A — Pathological fracture in neoplastic disease, pelvis, initial encounter for fracture, M84.551A — Pathological fracture in neoplastic disease, right femur, initial encounter for fracture, M84.552A — Pathological fracture in neoplastic disease, left femur, initial encounter for fracture, M84.553A — Pathological fracture in neoplastic disease, unspecified femur, initial encounter for fracture, +193 more

Same condition, opposite side

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

M84.531A — Pathological fracture in neoplastic disease, right ulna, initial encounter for fractureCompare M84.532A vs M84.531A →

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical categories (Pathological fracture, initial encounter, Conditions due to neoplasm or the treatment of neoplasm).

M84.479A — Pathological fracture, unspecified toe(s), initial encounter for fracture, M84.48XA — Pathological fracture, other site, initial encounter for fracture, M84.50XA — Pathological fracture in neoplastic disease, unspecified site, initial encounter for fracture, M84.511A — Pathological fracture in neoplastic disease, right shoulder, initial encounter for fracture, M84.512A — Pathological fracture in neoplastic disease, left shoulder, initial encounter for fracture, M84.519A — Pathological fracture in neoplastic disease, unspecified shoulder, initial encounter for fracture, M84.521A — Pathological fracture in neoplastic disease, right humerus, initial encounter for fracture, M84.522A — Pathological fracture in neoplastic disease, left humerus, initial encounter for fracture, M84.529A — Pathological fracture in neoplastic disease, unspecified humerus, initial encounter for fracture, M84.531A — Pathological fracture in neoplastic disease, right ulna, initial encounter for fracture, M84.533A — Pathological fracture in neoplastic disease, right radius, initial encounter for fracture, M84.534A — Pathological fracture in neoplastic disease, left radius, initial encounter for fracture, M84.539A — Pathological fracture in neoplastic disease, unspecified ulna and radius, initial encounter for fracture, M84.541A — Pathological fracture in neoplastic disease, right hand, initial encounter for fracture, M84.542A — Pathological fracture in neoplastic disease, left hand, initial encounter for fracture, M84.549A — Pathological fracture in neoplastic disease, unspecified hand, initial encounter for fracture, M84.550A — Pathological fracture in neoplastic disease, pelvis, initial encounter for fracture, M84.551A — Pathological fracture in neoplastic disease, right femur, initial encounter for fracture, M84.552A — Pathological fracture in neoplastic disease, left femur, initial encounter for fracture, M84.553A — Pathological fracture in neoplastic disease, unspecified femur, initial encounter for fracture, +160 more

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)

Lab tests where this diagnosis supports Medicare coverage (NCD)

Medicare's National Coverage Determination (NCD) program lists this diagnosis as medical justification for these lab tests.

Partial Thromboplastin Time (PTT) Test

Contextual Map

Every relationship of M84.532A 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 M84.532A 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
• M80-M85 — Disorders of bone density and structure[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026

Referenced by Excludes1 notes

• M84.4 — Pathological fracture, not elsewhere classified[Excludes1](via M84.5.-): “pathological fracture in neoplastic disease (M84.5-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Clinical classification (CCSR)

• MUS014 — Pathological fracture, initial encounter[CCSR]— AHRQ CCSR for ICD-10-CM Diagnoses (HCUP)
• NEO074 — Conditions due to neoplasm or the treatment of neoplasm[CCSR]— AHRQ CCSR for ICD-10-CM Diagnoses (HCUP)

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 542 — PATHOLOGICAL FRACTURES AND MUSCULOSKELETAL AND CONNECTIVE TISSUE MALIGNANCY WITH MCC[MS-DRG]: “PATHOLOGICAL FRACTURES AND MUSCULOSKELETAL AND CONNECTIVE TISSUE MALIGNANCY WITH MCC (MDC 08)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• DRG 543 — PATHOLOGICAL FRACTURES AND MUSCULOSKELETAL AND CONNECTIVE TISSUE MALIGNANCY WITH CC[MS-DRG]: “PATHOLOGICAL FRACTURES AND MUSCULOSKELETAL AND CONNECTIVE TISSUE MALIGNANCY WITH CC (MDC 08)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• DRG 544 — PATHOLOGICAL FRACTURES AND MUSCULOSKELETAL AND CONNECTIVE TISSUE MALIGNANCY WITHOUT CC/MCC[MS-DRG]: “PATHOLOGICAL FRACTURES AND MUSCULOSKELETAL AND CONNECTIVE TISSUE MALIGNANCY WITHOUT CC/MCC (MDC 08)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• DRG 791 — PREMATURITY WITH MAJOR PROBLEMS[MS-DRG]: “PREMATURITY WITH MAJOR PROBLEMS (MDC 15)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• DRG 793 — FULL TERM NEONATE WITH MAJOR PROBLEMS[MS-DRG]: “FULL TERM NEONATE WITH MAJOR PROBLEMS (MDC 15)”— 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
• MDC 15 — Newborns and Other Neonates with Conditions Originating in Perinatal Period[MDC crossing]: “Newborns and Other Neonates with Conditions Originating in Perinatal Period — 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.”— CMS MS-DRG Definitions Manual · FY2026

Nearest codes (40)

• M84 — Disorder of continuity of bone[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• M84.522G — Pathological fracture in neoplastic disease, left humerus, subsequent encounter for fracture with delayed healing[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• M84.522K — Pathological fracture in neoplastic disease, left humerus, subsequent encounter for fracture with nonunion[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• M84.522P — Pathological fracture in neoplastic disease, left humerus, subsequent encounter for fracture with malunion[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• M84.522S — Pathological fracture in neoplastic disease, left humerus, sequela[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• M84.529 — Pathological fracture in neoplastic disease, unspecified humerus[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• M84.529A — Pathological fracture in neoplastic disease, unspecified humerus, initial encounter for fracture[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• M84.529D — Pathological fracture in neoplastic disease, unspecified humerus, subsequent encounter for fracture with routine healing[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

Relevant guides

• Traumatic, Pathological, or Stress Fracture: Which Family, and the Osteoporosis Rule →

Common coding questions

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

Coding guidelines Official source data

ICD-10-CM Official Guidelines for Coding and Reporting (FY2026), quoted by section 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

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

Nearest Codes in This Family

Official ICD-10-CM classifications closest to M84.532A in its code family, with their registry titles.

• M84.531G — Pathological fracture in neoplastic disease, right ulna, subsequent encounter for fracture with delayed healing
• M84.531K — Pathological fracture in neoplastic disease, right ulna, subsequent encounter for fracture with nonunion
• M84.531P — Pathological fracture in neoplastic disease, right ulna, subsequent encounter for fracture with malunion
• M84.531S — Pathological fracture in neoplastic disease, right ulna, sequela
• M84.532 — Pathological fracture in neoplastic disease, left ulna
• M84.532D — Pathological fracture in neoplastic disease, left ulna, subsequent encounter for fracture with routine healing
• M84.532G — Pathological fracture in neoplastic disease, left ulna, subsequent encounter for fracture with delayed healing
• M84.532K — Pathological fracture in neoplastic disease, left ulna, subsequent encounter for fracture with nonunion
• M84.532P — Pathological fracture in neoplastic disease, left ulna, subsequent encounter for fracture with malunion
• M84.532S — Pathological fracture in neoplastic disease, left ulna, sequela

View all codes in the M84 family