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S90.559D ICD-10-CM Code: Superficial foreign body, unspecified ankle, subsequent encounter

Compare with another codeCheck 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
4 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; the Instructions section marks which is which.

Excludes2Not included here; may be reported together
  • burns and corrosions (T20-T32)
  • fracture of ankle and malleolus (S82.-)
  • frostbite (T33-T34)
  • insect bite or sting, venomous (T63.4)

Most relevant related codes MedCoder-derived

Read off the official notes above and this code’s own position in the tabular list. Which to report is a documentation question; Compare shows the two side by side.

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.

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 S90.559D 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 S90.559D 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.

Source: inherited from S90-S99

7th Character Guide

"The appropriate 7th character is to be added to each code from category S90"

  • 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

S90.559A, S90.559D, S90.559S

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 S90.559D

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

Before you code S90.559D

  1. Unspecified does not mean incorrect. When the record gives no greater specificity, S90.559D 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).

    ReviewS90.551D, S90.552D

    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).

    ReviewS90.551D · right, S90.552D · 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 →

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 — S90.559D is appropriate when the documentation goes no further.

    ReviewS90.551D, S90.552D

  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.

    ReviewS90.551D · right, S90.552D · left

  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 S90.559D. 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).
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).
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

  • Excludes2 — not part of S90.559D(4 notes)

    Coding workflow: The conditions named in this note are not included in S90.559D. When the record documents both, both may be reported; the note is a boundary, not a prohibition.

    CompareS82, T63.4

    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 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).

ReviewS90.551D, S90.552D

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).

ReviewS90.551D · right, S90.552D · left

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 S90.559D with…

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

The codes most likely to be picked instead of S90.559D — 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.

  • S90.551D— 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 S90.551D.

    Full comparison: S90.559D vs S90.551D →

  • S90.552D— 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 S90.552D.

    Full comparison: S90.559D vs S90.552D →

  • S90.559A— 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 S90.559A.

    Full comparison: S90.559D vs S90.559A →

  • S90.559S— 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 sequela moves the case to S90.559S.

    Full comparison: S90.559D vs S90.559S →

  • T20— 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 burns and corrosions adds T20; it is not part of this code and both may be reported when both are documented.

    Full comparison: S90.559D vs T20 →

  • T32— 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 burns and corrosions adds T32; it is not part of this code and both may be reported when both are documented.

    Full comparison: S90.559D vs T32 →

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

Superficial foreign body, unspecified ankle, subsequent encounter is a billable ICD-10-CM diagnosis code (S90.559D).

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

  • 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-derived relationships — computed from published CMS and AHRQ datasets

Other codes that name S90.559D 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 11 Excludes2 notes: S80 — Superficial injury of knee and lower leg (via S90.-), S80-S89 — Injuries to the knee and lower leg (S80-S89) (via S90.-), S81 — Open wound of knee and lower leg (via S90.-), S82 — Fracture of lower leg, including ankle (via S90.-), S83 — Dislocation and sprain of joints and ligaments of knee (via S90.-), S84 — Injury of nerves at lower leg level (via S90.-), S85 — Injury of blood vessels at lower leg level (via S90.-), S86 — Injury of muscle, fascia and tendon at lower leg level (via S90.-), S87 — Crushing injury of lower leg (via S90.-), S88 — Traumatic amputation of lower leg (via S90.-), S89 — Other and unspecified injuries of lower leg (via S90.-).

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 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):INJ054 — Superficial injury; contusion, 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.

S90.551D — Superficial foreign body, right ankle, subsequent encounter (right)Compare S90.559D vs S90.551D →, S90.552D — Superficial foreign body, left ankle, subsequent encounter (left)Compare S90.559D vs S90.552D →

Same injury, other encounter phase

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

S90.559A — Superficial foreign body, unspecified ankle, initial encounterCompare S90.559D vs S90.559A →, S90.559S — Superficial foreign body, unspecified ankle, sequela

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical category (Superficial injury; contusion, subsequent encounter).

+763 more

Same Index main term, other category

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

S50.85 — Superficial foreign body of forearm (superficial, without open wound, forearm), S60.35 — Superficial foreign body of thumb (superficial, without open wound, thumb), S60.45 — Superficial foreign body of fingers (superficial, without open wound, finger, ring), S60.459 — Superficial foreign body of unspecified finger (superficial, without open wound, finger), S60.55 — Superficial foreign body of hand (superficial, without open wound, hand), S60.85 — Superficial foreign body of wrist (superficial, without open wound, wrist), S70.25 — Superficial foreign body of hip (superficial, without open wound, hip), S70.35 — Superficial foreign body of thigh (superficial, without open wound, thigh), S80.25 — Superficial foreign body of knee (superficial, without open wound, knee), S80.85 — Superficial foreign body of lower leg (superficial, without open wound, leg), T15.0 — Foreign body in cornea (cornea), T15.1 — Foreign body in conjunctival sac (conjunctival sac), T15.8 — Foreign body in other and multiple parts of external eye (entering through orifice, eye NOS, specified part NEC), T15.9 — Foreign body on external eye, part unspecified (entering through orifice, eye NOS), T17.0 — Foreign body in nasal sinus (respiratory tract, nasal sinus), T17.1 — Foreign body in nostril (respiratory tract, nose), T17.200 — Unspecified foreign body in pharynx causing asphyxiation (pharynx, causing, asphyxiation), T17.208 — Unspecified foreign body in pharynx causing other injury (pharynx), T17.210 — Gastric contents in pharynx causing asphyxiation (pharynx, causing, asphyxiation, gastric contents), T17.218 — Gastric contents in pharynx causing other injury (pharynx, causing, injury NEC, gastric contents), +176 more

Contextual Map

Every relationship of S90.559D 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 S90.559D with these 8 related codes in Claim Check

Hierarchy

Referenced by Excludes2 notes (11)

Clinical classification (CCSR)

MS-DRG Grouper

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. 1,258 same-MDC procedures group here; browse them on the MDC page.”— CMS MS-DRG Definitions Manual · FY2027

Nearest codes (40)

Change history

  • FY2016 — In the code set at ICD-10-CM adoption [Change history]— CMS release files (code change ledger) · icd10cm-fy2016

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 S90.559D require a 7th character?

Yes. The appropriate 7th character is to be added to each code from category S90.

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 20, 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. "S90.559D — Superficial foreign body, unspecified ankle, subsequent encounter." ICD-10-CM FY2027. https://medcoder.ai/icd10/code/s90.559d-superficial-foreign-body-unspecified-ankle-subsequent-encounter

Change history

  • FY2016 — October 1, 2015
    In the code set at ICD-10-CM adoption
    Superficial foreign body, unspecified ankle, subsequent encounter

No changes since FY2016 — additions, deletions, description changes and billable-status changes are tracked through FY2027, and none are recorded for this code. Note changes are tracked from FY2027 only.

Nearest Codes in This Family

Official ICD-10-CM classifications closest to S90.559D in its code family, with their registry titles.

View all codes in the S90 family