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M84.750A ICD-10-CM Code: Atypical femoral fracture, unspecified, initial encounter for fracture

Compare with another code for M84.750ACheck this code on a claim

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

Coding at a Glance

7th character
Required — see the character table on this page
Tabular directives
1 Excludes2

Billable · FY2027A valid, specific ICD-10-CM code, reportable for dates of service in FY2027.

What you need to know

Source: CMS/NCHS Official ICD-10-CM tabular notes, quoted. From the CMS/NCHS tabular list for the release in force. A note the category or block publishes applies to this code too, and is marked with where it comes from.

7th character:A· The appropriate 7th character is to be added to each code from M84.75:All 7th characters

Excludes2from M84Not included here; may be reported together
  • traumatic fracture of bone-see fracture, by site

Where it sits Source: CMS/NCHS

Under:Chapter 13: Diseases of the Musculoskeletal System and Connective TissueM80-M94 Osteopathies and chondropathiesM80-M85 Disorders of bone density and structureM84 Disorder of continuity of boneM84.7 Nontraumatic fracture, not elsewhere classifiedM84.75 Atypical femoral fractureM84.750 Atypical femoral fracture, unspecified

CompareCheck ClaimView Related Codes

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 v44, Appendix B.

  • MS-DRG 521 — HIP REPLACEMENT WITH PRINCIPAL DIAGNOSIS OF HIP FRACTURE WITH MCC (MDC 08)
  • MS-DRG 522 — HIP REPLACEMENT WITH PRINCIPAL DIAGNOSIS OF HIP FRACTURE WITHOUT MCC (MDC 08)
  • MS-DRG 542 — PATHOLOGICAL FRACTURES AND MUSCULOSKELETAL AND CONNECTIVE TISSUE MALIGNANCY WITH MCC (MDC 08)
  • MS-DRG 543 — PATHOLOGICAL FRACTURES AND MUSCULOSKELETAL AND CONNECTIVE TISSUE MALIGNANCY WITH CC (MDC 08)
  • MS-DRG 544 — PATHOLOGICAL FRACTURES AND MUSCULOSKELETAL AND CONNECTIVE TISSUE MALIGNANCY WITHOUT CC/MCC (MDC 08)
  • MS-DRG 791 — PREMATURITY WITH MAJOR PROBLEMS (MDC 15)
  • MS-DRG 793 — FULL TERM NEONATE WITH MAJOR PROBLEMS (MDC 15)

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.

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for M84.750A in the official ICD-10-CM tabular list, quoted as published.

Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2027Effective: October 1, 2026

Trace:FY2027 changesChange historyRelease, file and checksum

Notes without a marker are published on M84.750A itself; “inherited from” names the category or block whose note applies here.

Excludes2 — Not Included Here

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

  • traumatic fracture of bone-see fracture, by site

Source: inherited from M84

7th Character Guide

"The appropriate 7th character is to be added to each code from M84.75:"

  • 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

M84.750A, M84.750D, M84.750G, M84.750K, M84.750P, M84.750S

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 M84.750A

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

Before you code M84.750A

  1. Unspecified does not mean incorrect. When the record gives no greater specificity, M84.750A 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).

    ReviewM84.751A, M84.752A

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

  2. 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 →

  3. 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).

    See the relationships section · Guide: Laterality coding →

Choose the right path

  1. Does the record document the detail a more specific sibling code needs?
    Yes → Review the specific siblings in this subcategory.
    No → Continue — M84.750A is appropriate when the documentation goes no further.

    ReviewM84.751A, M84.752A

  2. 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.
  3. 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 M84.750A. 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 code would capture — or its absence, which itself supports the unspecified code.

Official instructions as workflow

  • Excludes2 — not part of M84.750A(1 note)

    Coding workflow: The conditions named in this note are not included in M84.750A. 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

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).

ReviewM84.751A, M84.752A

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).

Documentation: The record documents the condition on one side only.

Coding question: Which code in this family applies?

Path: Select the sibling code for the documented side.

Reason: Laterality is assigned from the documented side; the unspecified-side code is for records that state no side (Guidelines I.B.13).

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.

Don’t confuse M84.750A with…

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

The codes most likely to be picked instead of M84.750A — 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.

  • M84.750D— 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 M84.750D.

    Full comparison: M84.750A vs M84.750D →

  • M84.750G— 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 M84.750G.

    Full comparison: M84.750A vs M84.750G →

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.

Coding context

Guidelines, coding notes, decision aids, relationships (with MS-DRG and CCSR classification), hierarchy, HCC, coverage and the context map: what a coder reaches for after the core. Each section names whether it is official source data, a MedCoder-derived relationship or MedCoder editorial.

Code Overview

Atypical femoral fracture, unspecified, initial encounter for fracture is a billable ICD-10-CM diagnosis code (M84.750A).

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

Verify Before Coding

  • CC as a secondary diagnosis (FY2027). 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-derived relationships — computed from published CMS and AHRQ datasets

MS-DRG Grouper Relationships (FY2027)

Potential MS-DRG participation — not a DRG assignment.

FY2027 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 214 clinically related codes on its CMS exclusion list.

Named in the grouper logic of 7 MS-DRGs: DRG 521 (MDC 08), DRG 522 (MDC 08), 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):MUS018 — Atypical fracture, initial encounter (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.

M84.662A — Pathological fracture in other disease, left tibia, initial encounter for fracture, M84.663A — Pathological fracture in other disease, right fibula, initial encounter for fracture, M84.664A — Pathological fracture in other disease, left fibula, initial encounter for fracture, M84.669A — Pathological fracture in other disease, unspecified tibia and fibula, initial encounter for fracture, M84.671A — Pathological fracture in other disease, right ankle, initial encounter for fracture, M84.672A — Pathological fracture in other disease, left ankle, initial encounter for fracture, M84.673A — Pathological fracture in other disease, unspecified ankle, initial encounter for fracture, M84.674A — Pathological fracture in other disease, right foot, initial encounter for fracture, M84.675A — Pathological fracture in other disease, left foot, initial encounter for fracture, M84.676A — Pathological fracture in other disease, unspecified foot, initial encounter for fracture, M84.68XA — Pathological fracture in other disease, other site, initial encounter for fracture, M84.751A — Incomplete atypical femoral fracture, right leg, initial encounter for fracture, M84.752A — Incomplete atypical femoral fracture, left leg, initial encounter for fracture, M84.753A — Incomplete atypical femoral fracture, unspecified leg, initial encounter for fracture, M84.754A — Complete transverse atypical femoral fracture, right leg, initial encounter for fracture, M84.755A — Complete transverse atypical femoral fracture, left leg, initial encounter for fracture, M84.756A — Complete transverse atypical femoral fracture, unspecified leg, initial encounter for fracture, M84.757A — Complete oblique atypical femoral fracture, right leg, initial encounter for fracture, M84.758A — Complete oblique atypical femoral fracture, left leg, initial encounter for fracture, M84.759A — Complete oblique atypical femoral fracture, unspecified leg, initial encounter for fracture, +193 more

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical category (Atypical fracture, initial encounter).

M84.751A — Incomplete atypical femoral fracture, right leg, initial encounter for fracture, M84.752A — Incomplete atypical femoral fracture, left leg, initial encounter for fracture, M84.753A — Incomplete atypical femoral fracture, unspecified leg, initial encounter for fracture, M84.754A — Complete transverse atypical femoral fracture, right leg, initial encounter for fracture, M84.755A — Complete transverse atypical femoral fracture, left leg, initial encounter for fracture, M84.756A — Complete transverse atypical femoral fracture, unspecified leg, initial encounter for fracture, M84.757A — Complete oblique atypical femoral fracture, right leg, initial encounter for fracture, M84.758A — Complete oblique atypical femoral fracture, left leg, initial encounter for fracture, M84.759A — Complete oblique atypical femoral fracture, unspecified leg, initial encounter for fracture

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.

Iron Panel

Contextual Map

Every relationship of M84.750A 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

Clinical classification (CCSR)

MS-DRG Grouper

MDC crossing

Nearest codes (40)

Change history

Reference

Index terms and tables, published questions and FAQ, every source behind this page with its release and checksum, the date-of-service check and the complete change history.

Common coding questions

MedCoder editorial

Does M84.750A require a 7th character?

Yes. The appropriate 7th character is to be added to each code from M84.75:.

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 FY2027 tabular list, index and tables, effective October 1, 2026 Release, file and checksum · Publisher’s page
Claim edits Official source data
CMS Definitions of Medicare Code Edits — v44.0 (October 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 — v44 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-derived 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 editorial 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.

Current data releases:ICD-10-CM FY2027 · ICD-10-PCS FY2027 · HCPCS October 2026 · MS-DRG v44 · Medicare Code Editor v44.0 · NCCI PTP Q4 2026 · MUE Q4 2026 · NCD code lists 2026-01 · LCD export September 28, 2026 · All releases and sources

Labels on this page: Official source data · MedCoder-derived relationship · MedCoder editorial explanation. How to read the labels · All data sources and release dates · CMS coding rules

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. "M84.750A — Atypical femoral fracture, unspecified, initial encounter for fracture." ICD-10-CM FY2027. https://medcoder.ai/icd10/code/m84.750a-atypical-femoral-fracture-unspecified-initial-encounter-for-fracture

Change history

  • FY2017 — October 1, 2016
    Added to the code set
    Atypical femoral fracture, unspecified, initial encounter for fracture
    FY2017 changes

Nearest Codes in This Family

Official ICD-10-CM classifications closest to M84.750A in its code family, with their registry titles.

View all codes in the M84 family