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M26.602 ICD-10-CM Code: Left temporomandibular joint disorder, unspecified

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

Coding at a Glance

Tabular directives
2 Excludes1 · 2 Excludes2

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 011 — TRACHEOSTOMY FOR FACE, MOUTH AND NECK DIAGNOSES OR LARYNGECTOMY WITH MCC (MDC PRE)
  • MS-DRG 012 — TRACHEOSTOMY FOR FACE, MOUTH AND NECK DIAGNOSES OR LARYNGECTOMY WITH CC (MDC PRE)
  • MS-DRG 013 — TRACHEOSTOMY FOR FACE, MOUTH AND NECK DIAGNOSES OR LARYNGECTOMY WITHOUT CC/MCC (MDC PRE)
  • MS-DRG 157 — DENTAL AND ORAL DISEASES WITH MCC (MDC 03)
  • MS-DRG 158 — DENTAL AND ORAL DISEASES WITH CC (MDC 03)
  • MS-DRG 159 — DENTAL AND ORAL DISEASES WITHOUT CC/MCC (MDC 03)

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 M26.602 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 M26.602 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 M26-M27

Excludes2 — Not Included Here

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

Source: inherited from M26.6

Coder workflow for M26.602

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

Before you code M26.602

  1. Unspecified does not mean incorrect. When the record gives no greater specificity, M26.602 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).

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

  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).

    ReviewM26.601 · right, M26.603 · bilateral

    Guide: Laterality coding →

  3. Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with M26.602. 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 record document the detail a more specific sibling code needs?
    Yes → Review the specific siblings in this subcategory.
    No → Continue — M26.602 is appropriate when the documentation goes no further.
  2. Does the documentation support a condition named in M26.602’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.

    ReviewQ67.4, M27.8

  3. 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.

    ReviewM26.601 · right, M26.603 · bilateral

Consider M26.602. 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).
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 M26.602(2 notes)

    Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with M26.602: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.

    CompareQ67.4, M27.8

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

  • Excludes2 — not part of M26.602(2 notes)

    Coding workflow: The conditions named in this note are not included in M26.602. When the record documents both, both may be reported; the note is a boundary, not a prohibition.

    CompareS03.0, S03.4

    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 subcategory for a sibling that names the missing detail.

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).

Documentation: Both the condition M26.602 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).

ReviewQ67.4, M27.8

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).

ReviewM26.601 · right, M26.603 · bilateral

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 M26.602 with…

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

The codes most likely to be picked instead of M26.602 — 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.

  • Q67.4— 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 hemifacial atrophy or hypertrophy moves the case to Q67.4; the two are not reported together unless documented as unrelated.

    Full comparison: M26.602 vs Q67.4 →

  • M27.8— 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 unilateral condylar hyperplasia or hypoplasia moves the case to M27.8; the two are not reported together unless documented as unrelated.

    Full comparison: M26.602 vs M27.8 →

  • M26.601— 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 M26.601.

    Full comparison: M26.602 vs M26.601 →

  • M26.603— 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: Documentation of both sides moves the case to M26.603.

    Full comparison: M26.602 vs M26.603 →

  • S03.0— 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 current temporomandibular joint dislocation adds S03.0; it is not part of this code and both may be reported when both are documented.

    Full comparison: M26.602 vs S03.0 →

  • S03.4— 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 current temporomandibular joint sprain adds S03.4; it is not part of this code and both may be reported when both are documented.

    Full comparison: M26.602 vs S03.4 →

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.

Code Overview

Left temporomandibular joint disorder, unspecified is a billable ICD-10-CM diagnosis code (M26.602).

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. 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. 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

  • No Medicare Code Editor or MS-DRG Definitions Manual restrictions apply to this code.

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 M26.602 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 4 Excludes1 notes: Q18 — Other congenital malformations of face and neck (via M26.-), Q38 — Other congenital malformations of tongue, mouth and pharynx (via M26.-), Q67.4 — Other congenital deformities of skull, face and jaw (via M26.-), Q75 — Other congenital malformations of skull and face bones (via M26.-).

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

Referenced by 4 Excludes2 notes across 2 chapters: K08 — Other disorders of teeth and supporting structures (via M26.-), M24 — Other specific joint derangements (via M26.6.-), M25 — Other joint disorder, not elsewhere classified (via M26.6.-), M95 — Other acquired deformities of musculoskeletal system and connective tissue (via M26.-).

These codes’ tabular lists name this diagnosis as distinct — both may be reported when both are documented.

MS-DRG Grouper Relationships (FY2027)

Potential MS-DRG participation — not a DRG assignment.

FY2027 MS-DRG: not on the CMS CC/MCC list — as a secondary diagnosis this code does not change MS-DRG severity for that release.

Named in the grouper logic of 6 MS-DRGs: DRG 011 (MDC PRE), DRG 012 (MDC PRE), DRG 013 (MDC PRE), DRG 157 (MDC 03), DRG 158 (MDC 03), DRG 159 (MDC 03).

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

Clinical classification (AHRQ CCSR):MUS029 — Disorders of jaw (default); DEN001 — Any dental condition including traumatic injury; DEN002 — Nontraumatic dental conditions.

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 condition, opposite side

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

M26.601 — Right temporomandibular joint disorder, unspecified (right)Compare M26.602 vs M26.601 →, M26.603 — Bilateral temporomandibular joint disorder, unspecified (bilateral)Compare M26.602 vs M26.603 →

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical categories (Disorders of jaw, Any dental condition including traumatic injury, Nontraumatic dental conditions).

M26.51 — Abnormal jaw closure, M26.52 — Limited mandibular range of motion, M26.53 — Deviation in opening and closing of the mandible, M26.54 — Insufficient anterior guidance, M26.55 — Centric occlusion maximum intercuspation discrepancy, M26.56 — Non-working side interference, M26.57 — Lack of posterior occlusal support, M26.59 — Other dentofacial functional abnormalities, M26.60 — Temporomandibular joint disorder, unspecified, M26.601 — Right temporomandibular joint disorder, unspecified, M26.603 — Bilateral temporomandibular joint disorder, unspecified, M26.609 — Unspecified temporomandibular joint disorder, unspecified side, M26.61 — Adhesions and ankylosis of temporomandibular joint, M26.611 — Adhesions and ankylosis of right temporomandibular joint, M26.612 — Adhesions and ankylosis of left temporomandibular joint, M26.613 — Adhesions and ankylosis of bilateral temporomandibular joint, M26.619 — Adhesions and ankylosis of temporomandibular joint, unspecified side, M26.62 — Arthralgia of temporomandibular joint, M26.621 — Arthralgia of right temporomandibular joint, M26.622 — Arthralgia of left temporomandibular joint, +613 more

Same Index main term, other category

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

H57.04 — Mydriasis (pupil, function, mydriasis), H57.05 — Tonic pupil (pupil, function, tonic pupil), H57.09 — Other anomalies of pupillary function (pupil, function, specified type NEC), I42.4 — Endocardial fibroelastosis (heart, fibroelastosis cordis), I45.6 — Pre-excitation syndrome (atrioventricular, excitation), K00.2 — Abnormalities of size and form of teeth (form, teeth), K00.6 — Disturbances in tooth eruption (tooth, teeth, eruption), K00.9 — Disorder of tooth development, unspecified (tooth, teeth), K04.3 — Abnormal hard tissue formation in pulp (hard tissue formation in pulp), L81.9 — Disorder of pigmentation, unspecified (pigmentation), P83.5 — Congenital hydrocele (genitalia, genital organor system, male, hydrocele), Q00.0 — Anencephaly (hemicrania), Q02 — Microcephaly (skull, with, microcephaly), Q03.0 — Malformations of aqueduct of Sylvius (aqueduct of Sylvius), Q03.9 — Congenital hydrocephalus, unspecified (skull, with, hydrocephalus), Q04.8 — Other specified congenital malformations of brain (meninges, cerebral), Q04.9 — Congenital malformation of brain, unspecified (dura), Q05.9 — Spina bifida, unspecified (meningocele), Q06.3 — Other congenital cauda equina malformations (cauda equina), Q06.9 — Congenital malformation of spinal cord, unspecified (meninges, spinal), +204 more

Contextual Map

Every relationship of M26.602 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 M26.602 with these 8 related codes in Claim Check

Hierarchy

Referenced by Excludes1 notes

Referenced by Excludes2 notes

Clinical classification (CCSR)

MS-DRG Grouper

MDC crossing

  • Pre-MDC[MDC crossing]: “Pre-MDC — 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. 175 same-MDC procedures group here; browse them on the MDC page.”— CMS MS-DRG Definitions Manual · FY2027
  • MDC 03 — Diseases and Disorders of the Ear, Nose, Mouth and Throat[MDC crossing]: “Diseases and Disorders of the Ear, Nose, Mouth and Throat — 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. 5,151 same-MDC procedures group here; browse them on the MDC page.”— CMS MS-DRG Definitions Manual · FY2027

Nearest codes (40)

Change history

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 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. "M26.602 — Left temporomandibular joint disorder, unspecified." ICD-10-CM FY2027. https://medcoder.ai/icd10/code/m26.602-left-temporomandibular-joint-disorder-unspecified

Change history

  • FY2017 — October 1, 2016
    Added to the code set
    Left temporomandibular joint disorder, unspecified
    FY2017 changes

Nearest Codes in This Family

Official ICD-10-CM classifications closest to M26.602 in its code family, with their registry titles.

View all codes in the M26 family