M25.042 ICD-10-CM Code: Hemarthrosis, left hand

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for M25.042 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 M25.042 itself; “inherited from” names the category or block whose note applies here.

Coder workflow for M25.042

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

Before you code M25.042

1. 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).

   ReviewM25.041 · right, M25.049 · unspecified

   Guide: Laterality coding →

2. Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with M25.042. 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 a condition named in M25.042’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.

   ReviewM36.2

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.

   ReviewM25.041 · right, M25.049 · unspecified

Consider M25.042. 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).

Official instructions as workflow

• Excludes1 — check before selecting M25.042(2 notes)

  Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with M25.042: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.

  CompareM36.2

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

• Excludes2 — not part of M25.042(8 notes)

  Coding workflow: The conditions named in this note are not included in M25.042. When the record documents both, both may be reported; the note is a boundary, not a prohibition.

  CompareR26, M71.4, M75.3, M65.2, R26.2, M26.6

  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

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 M25.042 with…

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

The codes most likely to be picked instead of M25.042 — 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.

• M36.2— 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 hemophilic arthropathy moves the case to M36.2; the two are not reported together unless documented as unrelated.

  Full comparison: M25.042 vs M36.2 →

• M25.049— Specificity relationship (Review)

  Overlapping diagnoses in the same category.

  Overlapping codes in the same category — the documentation decides which is the more specific fit.

  What moves you there: A record that documents no more than “Hemarthrosis, unspecified hand” takes M25.049; specificity in the record moves it back here.

  Full comparison: M25.042 vs M25.049 →

• M25.041— 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 M25.041.

  Full comparison: M25.042 vs M25.041 →

• R26— 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 abnormality of gait and mobility adds R26; it is not part of this code and both may be reported when both are documented.

  Full comparison: M25.042 vs R26 →

• M20— 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 acquired deformities of limb adds M20; it is not part of this code and both may be reported when both are documented.

  Full comparison: M25.042 vs M20 →

• M21— 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 acquired deformities of limb adds M21; it is not part of this code and both may be reported when both are documented.

  Full comparison: M25.042 vs M21 →

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. 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
2. 2 Excludes1 entries — codes named there are generally not reported together with this code (Guidelines I.A.12.a). See the Excludes1 notes
3. 8 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

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 11 clinically related codes on its CMS exclusion list.

Named in the grouper logic of 2 MS-DRGs: DRG 553 (MDC 08), DRG 554 (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):MUS007 — Other specified joint disorders (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.

M25.00 — Hemarthrosis, unspecified joint, M25.031 — Hemarthrosis, right wrist, M25.032 — Hemarthrosis, left wrist, M25.039 — Hemarthrosis, unspecified wrist, M25.041 — Hemarthrosis, right hand, M25.049 — Hemarthrosis, unspecified hand, M25.08 — Hemarthrosis, other specified site, T79.A11A — Traumatic compartment syndrome of right upper extremity, initial encounter, T79.A12A — Traumatic compartment syndrome of left upper extremity, initial encounter, T79.A19A — Traumatic compartment syndrome of unspecified upper extremity, initial encounter

Same condition, opposite side

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

M25.041 — Hemarthrosis, right hand (right)Compare M25.042 vs M25.041 →, M25.049 — Hemarthrosis, unspecified hand (unspecified)Compare M25.042 vs M25.049 →

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical category (Other specified joint disorders).

+741 more

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 M25.042 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]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• M00-M25 — Arthropathies[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• M20-M25 — Other joint disorders[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026

Clinical classification (CCSR)

• MUS007 — Other specified joint disorders[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 553 — BONE DISEASES AND ARTHROPATHIES WITH MCC[MS-DRG]: “BONE DISEASES AND ARTHROPATHIES WITH MCC (MDC 08)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• DRG 554 — BONE DISEASES AND ARTHROPATHIES WITHOUT MCC[MS-DRG]: “BONE DISEASES AND ARTHROPATHIES WITHOUT 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

Nearest codes (40)

• M25 — Other joint disorder, not elsewhere classified[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• M25.0 — Hemarthrosis[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• M25.00 — Hemarthrosis, unspecified joint[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• M25.01 — Hemarthrosis, shoulder[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• M25.011 — Hemarthrosis, right shoulder[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• M25.012 — Hemarthrosis, left shoulder[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• M25.019 — Hemarthrosis, unspecified shoulder[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• M25.02 — Hemarthrosis, elbow[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

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 M25.042 in its code family, with their registry titles.

• M25.031 — Hemarthrosis, right wrist
• M25.032 — Hemarthrosis, left wrist
• M25.039 — Hemarthrosis, unspecified wrist
• M25.04 — Hemarthrosis, hand
• M25.041 — Hemarthrosis, right hand
• M25.049 — Hemarthrosis, unspecified hand
• M25.05 — Hemarthrosis, hip
• M25.051 — Hemarthrosis, right hip
• M25.052 — Hemarthrosis, left hip
• M25.059 — Hemarthrosis, unspecified hip

View all codes in the M25 family