Skip to main content

S33.131 vs T63.4

S33.131 (Dislocation of L3/L4 lumbar vertebra) compared with T63.4 (Toxic effect of venom of other arthropods), from the official CMS tabular data.

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

Summary

These codes can be reported together when both conditions are documented, because S33.131 lists T63.4 under Excludes2, which marks them as distinct conditions.

Official rule
What is different?

The conditions named.S33.131 is “Dislocation of L3/L4 lumbar vertebra”; T63.4 is “Toxic effect of venom of other arthropods”.

Registry fact

Can these codes be reported together?

Yes, when both are documented.S33.131 lists T63.4 under Excludes2: “insect bite or sting, venomous (T63.4)”. Excludes2 marks distinct conditions that may both be reported when both are documented.

Official ruleGuide: Excludes1 vs Excludes2

Is there an Excludes1 relationship?

None.Neither entry carries an Excludes1 note that names the other code. S33.131 carries 2 Excludes1 notes and T63.4 carries 1 Excludes1 note covering other codes; the side-by-side table quotes them.

Official rule

Is there an Excludes2 relationship?

Yes.S33.131’s tabular entry: “insect bite or sting, venomous (T63.4)”. The note covers T63.4.

Official ruleGuide: Excludes1 vs Excludes2

Is one more specific?

Not comparable.The codes sit in different categories; specificity is only comparable within one category.

Is one a parent or header code?

Both are headers.Both are non-billable headers, and neither contains the other.

Registry fact

Are there sequencing instructions?

None.Neither entry carries a Code First or Use Additional Code note that names the other.

Official rule

Are there other coding relationships?

None found.No laterality, encounter-phase, Table of Neoplasms, Table of Drugs and Chemicals, or history-versus-active-disease relationship links these codes.

MedCoder-derived

Official rule: a tabular instructional note or a section of the ICD-10-CM Official Guidelines, quoted as published. Registry fact: the codes’ own published attributes (titles, billable status, position in the hierarchy, code set). MedCoder-derived: a reading MedCoder computes from those facts; it is not itself a rule. How to read the labels

Can these codes be reported together?

Informational

Excludes2 relationship

S33.131
Dislocation of L3/L4 lumbar vertebra
↔
T63.4
Toxic effect of venom of other arthropods

What we found

Yes, when both are documented.S33.131 carries an Excludes2 note covering T63.4: “insect bite or sting, venomous (T63.4)”

Excludes2 marks distinct conditions — both may be reported when both are documented.

What to review

Report both only when the documentation supports both conditions; otherwise report the one documented.

Guide: Excludes1 vs Excludes2Check these on a claim

Why it matters

An Excludes2 note means the excluded condition is not part of the code above it, but a patient can have both. Report both when both are documented.

Source / rule

CMS ICD-10-CM tabular instructional notes

Official guidance behind these answers

  • Section I.A.12.b — Excludes2 · applies to: Excludes2

    A type 2 Excludes note represents “Not included here.” An excludes2 note indicates that the condition excluded is not part of the condition represented by the code, but a patient may have both conditions at the same time. When an Excludes2 note appears under a code, it is acceptable to use both the code and the excluded code together, when appropriate.

    ICD-10-CM Official Guidelines FY2027

Quoted from the ICD-10-CM Official Guidelines for Coding and Reporting in effect for the release shown. The tabular notes above are the code-level instruction; these sections are the convention that says how such a note is applied. Source document (CMS PDF) · Release and checksum

Side by side

Similar descriptions do not make codes interchangeable. The documentation and the official instructions decide which code applies.

Official descriptionDiffers
S33.131

Dislocation of L3/L4 lumbar vertebra

T63.4

Toxic effect of venom of other arthropods

StatusDiffers
S33.131
Non-billable header

A header is not reported on a claim; a code beneath it is.

Report instead: S33.131A, S33.131D, S33.131S

T63.4
Non-billable header

A header is not reported on a claim; a code beneath it is.

Report instead: T63.411A, T63.411D, T63.411S, T63.412A, T63.412D

Excludes1Differs
S33.131
  • nontraumatic rupture or displacement of lumbar intervertebral disc NOS (M51.-)
  • obstetric damage to pelvic joints and ligaments (O71.6)
T63.4
  • contact with and (suspected) exposure to toxic substances (Z77.-)
Excludes2Differs
S33.131
  • fracture of lumbar vertebrae (S32.0-)
  • dislocation and sprain of joints and ligaments of hip (S73.-)
  • strain of muscle of lower back and pelvis (S39.01-)
  • burns and corrosions (T20-T32)
  • effects of foreign body in anus and rectum (T18.5)
  • effects of foreign body in genitourinary tract (T19.-)
  • effects of foreign body in stomach, small intestine and colon (T18.2-T18.4)
  • frostbite (T33-T34)
  • insect bite or sting, venomous (T63.4)
T63.4
  • ingestion of toxic animal or plant (T61.-, T62.-)
Use additional codeDiffers
S33.131

None at this code

T63.4
  • code, if applicable, for anaphylactic shock (T78.2)
  • code(s):
  • for all associated manifestations of toxic effect, such as: respiratory conditions due to external agents (J60-J70)
Code alsoDiffers
S33.131
  • any associated:
  • open wound of abdomen, lower back and pelvis (S31)
  • spinal cord injury (S24.0, S24.1-, S34.0-, S34.1-)
  • any associated open wound
T63.4

None at this code

CategoryDiffers
S33.131

S33 Dislocation and sprain of joints and ligaments of lumbar spine and pelvis

T63.4

T63 Toxic effect of contact with venomous animals and plants

ChapterSame for both

S00-T88 — Injury, Poisoning and Certain Other Consequences of External Causes (S00-T88)

IncludesDiffers
S33.131
  • avulsion of joint or ligament of lumbar spine and pelvis
  • laceration of cartilage, joint or ligament of lumbar spine and pelvis
  • sprain of cartilage, joint or ligament of lumbar spine and pelvis
  • traumatic hemarthrosis of joint or ligament of lumbar spine and pelvis
T63.4
  • bite or touch of venomous animal
  • pricked or stuck by thorn or leaf
7th characterDiffers
S33.131
  • The appropriate 7th character is to be added to each code from category S33
T63.4
  • The appropriate 7th character is to be added to each code from category T63

No Code first note at either code.

Notes are the code’s own tabular entry, quoted as published. A note that names the other code is the one the verdict above rests on. In a row that differs, notes every code shares are dimmed.

Edit this comparisonCheck a whole claim

Derived from the official CMS ICD-10-CM tabular data (FY2027). A coding-rule comparison, not billing advice: payer-specific edits and medical-necessity policy are outside its scope. All data sources