S01.359D ICD-10-CM Code: Open bite of unspecified ear, subsequent encounter

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for S01.359D 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 S01.359D 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 category S01"

• A — initial encounter
• D — subsequent encounter (this page’s code)
• 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

S01.359A, S01.359D, S01.359S

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 S01.359D

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

Before you code S01.359D

1. Unspecified does not mean incorrect. When the record gives no greater specificity, S01.359D may be the appropriate code. Check the record for detail that supports a more specific sibling — in this subcategory the siblings differ by open versus closed. 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).

   ReviewS01.351D, S01.352D

   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 “D”. “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).

   ReviewS01.351D · right, S01.352D · left

   Guide: Laterality coding →

4. Confirm the injury type, the anatomical site at the most specific level documented, laterality where the family codes it, and the encounter for the 7th character. Each injury is coded separately unless the classification provides a combination code, and a superficial injury is not coded when a more severe injury of the same site is documented. Injury chapter guidelines (Guidelines I.C.19.b, I.C.19.b.1).

   Guide: 7th characters: initial, subsequent, sequela →

5. Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with S01.359D. 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 — S01.359D is appropriate when the documentation goes no further.

   ReviewS01.351D, S01.352D

2. Does the documentation support a condition named in S01.359D’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.

   ReviewS00.46, S00.47, S02

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.

   ReviewS01.351D · right, S01.352D · left

4. 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 S01.359D. 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).

Anatomical site

At the most specific level the record states; a site the classification separates cannot be assumed from a procedure or a measurement.

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).

External cause, place and activity

For the external cause codes reported with the injury or poisoning, where documented (Guidelines I.C.20.a).

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 S01.359D(2 notes)

  Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with S01.359D: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.

  CompareS00.46, S00.47, S02

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

• Excludes2 — not part of S01.359D(11 notes)

  Coding workflow: The conditions named in this note are not included in S01.359D. When the record documents both, both may be reported; the note is a boundary, not a prohibition.

  CompareS05, S08, T16, T17.3, T18.0, T17.2

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

• Code Also — related condition(6 notes)

  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.

  ReviewS04, S09.1, S06

  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.

Don’t confuse S01.359D with…

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

The codes most likely to be picked instead of S01.359D — 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.

• S00.46— 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 superficial bite of ear moves the case to S00.46; the two are not reported together unless documented as unrelated.

  Full comparison: S01.359D vs S00.46 →

• S00.47— 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 superficial bite of ear moves the case to S00.47; the two are not reported together unless documented as unrelated.

  Full comparison: S01.359D vs S00.47 →

• S02— 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 open skull fracture moves the case to S02; the two are not reported together unless documented as unrelated.

  Full comparison: S01.359D vs S02 →

• S01.351D— 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 S01.351D.

  Full comparison: S01.359D vs S01.351D →

• S01.352D— 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 left side moves the case to S01.352D.

  Full comparison: S01.359D vs S01.352D →

• S01.359A— 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 initial encounter moves the case to S01.359A.

  Full comparison: S01.359D vs S01.359A →

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. 6 Code Also notes — a second code may apply; the guidelines leave its sequencing to the circumstances of the encounter. See the Code Also notes
3. 2 Excludes1 entries — codes named there are generally not reported together with this code (Guidelines I.A.12.a). See the Excludes1 notes
4. 11 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 S01.359D 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: S00 — Superficial injury of head (via S01.-).

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

Referenced by 1 Excludes2 note: S09.3 — Other specified and unspecified injury of middle and inner ear (via S01.3.-).

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

Referenced by 6 Code Also instructions across 2 chapters: G96.00 — Cerebrospinal fluid leak, unspecified (via S01.-), G96.08 — Other cranial cerebrospinal fluid leak (via S01.-), G96.09 — Other spinal cerebrospinal fluid leak (via S01.-), S04 — Injury of cranial nerve (via S01.-), S06 — Intracranial injury (via S01.-), S09.1 — Injury of muscle and tendon of head (via S01.-).

These codes suggest coding this condition alongside when both are present.

MS-DRG Grouper Relationships (FY2026)

Potential MS-DRG participation — not a DRG assignment.

FY2026 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 2 MS-DRGs: DRG 949 (MDC 23), DRG 950 (MDC 23).

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

Clinical classification (AHRQ CCSR):INJ048 — Open wounds of head and neck, subsequent 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 condition, opposite side

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

S01.351D — Open bite of right ear, subsequent encounter (right)Compare S01.359D vs S01.351D →, S01.352D — Open bite of left ear, subsequent encounter (left)Compare S01.359D vs S01.352D →

Same injury, other encounter phase

Same injury, coded at a different phase of treatment via the 7th character.

S01.359A — Open bite of unspecified ear, initial encounterCompare S01.359D vs S01.359A →, S01.359S — Open bite of unspecified ear, sequela

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical category (Open wounds of head and neck, subsequent encounter).

S01.322D — Laceration with foreign body of left ear, subsequent encounter, S01.329D — Laceration with foreign body of unspecified ear, subsequent encounter, S01.331D — Puncture wound without foreign body of right ear, subsequent encounter, S01.332D — Puncture wound without foreign body of left ear, subsequent encounter, S01.339D — Puncture wound without foreign body of unspecified ear, subsequent encounter, S01.341D — Puncture wound with foreign body of right ear, subsequent encounter, S01.342D — Puncture wound with foreign body of left ear, subsequent encounter, S01.349D — Puncture wound with foreign body of unspecified ear, subsequent encounter, S01.351D — Open bite of right ear, subsequent encounter, S01.352D — Open bite of left ear, subsequent encounter, S01.401D — Unspecified open wound of right cheek and temporomandibular area, subsequent encounter, S01.402D — Unspecified open wound of left cheek and temporomandibular area, subsequent encounter, S01.409D — Unspecified open wound of unspecified cheek and temporomandibular area, subsequent encounter, S01.411D — Laceration without foreign body of right cheek and temporomandibular area, subsequent encounter, S01.412D — Laceration without foreign body of left cheek and temporomandibular area, subsequent encounter, S01.419D — Laceration without foreign body of unspecified cheek and temporomandibular area, subsequent encounter, S01.421D — Laceration with foreign body of right cheek and temporomandibular area, subsequent encounter, S01.422D — Laceration with foreign body of left cheek and temporomandibular area, subsequent encounter, S01.429D — Laceration with foreign body of unspecified cheek and temporomandibular area, subsequent encounter, S01.431D — Puncture wound without foreign body of right cheek and temporomandibular area, subsequent encounter, +136 more

Same Index main term, other category

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

S00.46 — Insect bite (nonvenomous) of ear (ear, superficial NEC, insect), S00.47 — Other superficial bite of ear (ear, superficial NEC), S00.561 — Insect bite (nonvenomous) of lip (lip, superficial NEC, insect), S00.562 — Insect bite (nonvenomous) of oral cavity (oral cavity, superficial NEC, insect), S00.571 — Other superficial bite of lip (lip, superficial NEC), S00.572 — Other superficial bite of oral cavity (oral cavity, superficial NEC), S00.86 — Insect bite (nonvenomous) of other part of head (cheek, superficial NEC, insect), S00.87 — Other superficial bite of other part of head (cheek, superficial NEC), S00.96 — Insect bite (nonvenomous) of unspecified part of head (head, superficial NEC, insect), S00.97 — Other superficial bite of unspecified part of head (head, superficial NEC), S10.16 — Insect bite (nonvenomous) of throat (larynx, superficial NEC, insect), S10.17 — Other superficial bite of throat (larynx, superficial NEC), S10.86 — Insect bite of other specified part of neck (thyroid, superficial NEC, insect), S10.87 — Other superficial bite of other specified part of neck (thyroid, superficial NEC), S10.96 — Insect bite of unspecified part of neck (neck, superficial NEC, insect), S10.97 — Other superficial bite of unspecified part of neck (neck, superficial NEC), S11.015 — Open bite of larynx (larynx), S11.025 — Open bite of trachea (trachea), S11.035 — Open bite of vocal cord (vocal cords), S11.15 — Open bite of thyroid gland (thyroid), +132 more

Contextual Map

Every relationship of S01.359D 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 S01.359D with these 8 related codes in Claim Check

Hierarchy

• S00-T88 — Chapter 19: Injury, Poisoning and Certain Other Consequences of External Causes (S00-T88) (S00-T88)[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• S00-S09 — Injuries to the head[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026

Referenced by Excludes1 notes

• S00 — Superficial injury of head[Excludes1](via S01.-): “open wound of head (S01.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Referenced by Excludes2 notes

• S09.3 — Other specified and unspecified injury of middle and inner ear[Excludes2](via S01.3.-): “injury to external ear (S00.4-, S01.3-, S08.1-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Referenced by Code Also instructions

• G96.00 — Cerebrospinal fluid leak, unspecified[Code Also](via S01.-): “head injury (S00-S09)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• G96.08 — Other cranial cerebrospinal fluid leak[Code Also](via S01.-): “head injury (S00 - S09)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• G96.09 — Other spinal cerebrospinal fluid leak[Code Also](via S01.-): “head injury (S00 - S09)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• S04 — Injury of cranial nerve[Code Also](via S01.-): “open wound of head (S01.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• S06 — Intracranial injury[Code Also](via S01.-): “open wound of head (S01.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• S09.1 — Injury of muscle and tendon of head[Code Also](via S01.-): “any associated open wound (S01.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Clinical classification (CCSR)

• INJ048 — Open wounds of head and neck, subsequent encounter[CCSR]— AHRQ CCSR for ICD-10-CM Diagnoses (HCUP)

MS-DRG Grouper

• DRG 949 — AFTERCARE WITH CC/MCC[MS-DRG]: “AFTERCARE WITH CC/MCC (MDC 23)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• DRG 950 — AFTERCARE WITHOUT CC/MCC[MS-DRG]: “AFTERCARE WITHOUT CC/MCC (MDC 23)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026

MDC crossing

• MDC 23 — Factors Influencing Health Status and Other Contacts with Health Services[MDC crossing]: “Factors Influencing Health Status and Other Contacts with Health Services — 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. 1,235 same-MDC procedures group here; browse them on the MDC page.”— CMS MS-DRG Definitions Manual · FY2026

Nearest codes (40)

• S01 — Open wound of head[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• S01.341S — Puncture wound with foreign body of right ear, sequela[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• S01.342 — Puncture wound with foreign body of left ear[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• S01.342A — Puncture wound with foreign body of left ear, initial encounter[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• S01.342D — Puncture wound with foreign body of left ear, subsequent encounter[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• S01.342S — Puncture wound with foreign body of left ear, sequela[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• S01.349 — Puncture wound with foreign body of unspecified ear[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• S01.349A — Puncture wound with foreign body of unspecified ear, initial encounter[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

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

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 S01.359D in its code family, with their registry titles.

• S01.352A — Open bite of left ear, initial encounter
• S01.352D — Open bite of left ear, subsequent encounter
• S01.352S — Open bite of left ear, sequela
• S01.359 — Open bite of unspecified ear
• S01.359A — Open bite of unspecified ear, initial encounter
• S01.359S — Open bite of unspecified ear, sequela
• S01.4 — Open wound of cheek and temporomandibular area
• S01.40 — Unspecified open wound of cheek and temporomandibular area
• S01.401 — Unspecified open wound of right cheek and temporomandibular area
• S01.401A — Unspecified open wound of right cheek and temporomandibular area, initial encounter

View all codes in the S01 family