ICD-10 Code S02.11CS: Type II occipital condyle fracture, right side, sequela

Key takeaways

ICD-10 code S02.11CS is a billable ICD-10-CM diagnosis code for a Type II occipital condyle fracture, right side, sequela

The code is valid in the FY2026 ICD-10-CM code set, which took effect on October 1, 2025

The 7th character S marks a sequela, meaning a residual effect that remains after the acute fracture phase has finished

Documentation must confirm Anderson-Montesano Type II, right-side laterality, and a residual condition caused by the original fracture

Code the residual condition first and list S02.11CS second, or the claim risks a denial on sequencing

ICD-10 code S02.11CS is a billable ICD-10-CM diagnosis code for a Type II occipital condyle fracture on the right side, reported as a sequela. You use it once the acute fracture has resolved and the patient still has a residual condition caused by that injury.

Occipital condyle fractures are rare, so the S02.11 family comes up less often than the rest of the skull chapter. This page covers the code structure, the full 7th character set, the sibling codes, and the documentation a coder needs.

S02.11CS at a glance

S02.11CS is valid in the FY2026 ICD-10-CM code set, which took effect on October 1, 2025. The table below has the essentials.

What S02.11CS means, character by character

Each character in S02.11CS carries a distinct clinical meaning. Coders who read the code as segments make fewer selection errors.

The occipital condyles are two bony projections at the base of the skull. They articulate with the first cervical vertebra, so a fracture here can compromise craniocervical stability. The AAPC code lookup lists S02.11CS as billable and valid, with no exclusion note that blocks its use in a sequela encounter.

Where S02.11CS sits in the ICD-10-CM hierarchy

The hierarchy tells you whether you have reached the most specific billable code. The CDC ICD-10-CM web tool shows the full tabular structure.

• S00-S09 – Injuries to the head (ICD-10-CM chapter)
• S02 – Fracture of skull and facial bones
• S02.1 – Fracture of base of skull
• S02.11 – Fracture of occiput
• S02.11C – Type II occipital condyle fracture, right side (base code, needs a 7th character)
• S02.11CS – Type II occipital condyle fracture, right side, sequela (billable)

S02.11C is not billable on its own. It has to carry a 7th character before it goes on a claim, and a submission without one gets rejected. The same parent-child structure runs through the rest of the S02 block, as with S02.121B.

The 7th character: which encounter type to use

The 7th character is mandatory on S02 fracture codes. It tells the payer which phase of care the encounter belongs to, and the wrong choice is a common first-pass denial.

Six 7th characters are valid on this code family, which is more than many lookup tools display. Check the tabular list before you rule one out. The delayed-healing extension works the same way on neighboring skull codes such as S02.81XG.

Malunion has its own extension, P, but skull fracture codes do not use it. You will find P further down the injury chapter instead, as with S49.029P.

Sequela vs. subsequent encounter

A sequela encounter is one where the acute injury phase is entirely over. The patient now presents with a residual condition caused by the original injury. That definition sits in Section I.C.19 of the FY2026 ICD-10-CM guidelines. The sequela code is sequenced after the code for the residual condition.

The 7th character always comes from the clinical note, not from the billing screen. Practice management software like Pabau helps at the next step instead. Its claims management software submits and tracks each claim, and it flags missing administrative details such as member IDs or authorization numbers.

Related occipital condyle fracture codes

The S02.11 family splits by fracture type (I, II, III) and by side (right, left, unspecified). Pick the sibling code from confirmed radiologic documentation of type and side. The CMS ICD-10-CM tabular list is the authoritative source for what is valid.

There is no bilateral occipital condyle fracture code in ICD-10-CM. Where both condyles are fractured, report the right-side and left-side codes separately. The 6th characters G and H are not bilateral codes either. They cover other fractures of the occiput outside the condyle.

Laterality errors are a documented audit risk, so cross-reference the imaging report before you assign a side. Where the record genuinely does not state a side, S02.111S is the honest choice for a Type II sequela. Encounter-type errors follow the same pattern across the injury chapter, as with S43.014D.

Anderson-Montesano classification and Type II fractures

The Anderson-Montesano classification (1988) is the framework behind fracture types I, II, and III. The type has to come from the clinical record, not from the coder’s reading of the imaging.

Type II fractures run from a basilar skull fracture line into the condyle, usually after blunt craniofacial trauma. They are generally stable, though they can involve the hypoglossal canal. Craniocervical injuries often carry a companion cord-injury code such as S14.119S.

The treating clinician or radiologist has to state the type explicitly. Coders should not infer it from the mechanism of injury alone.

Documentation requirements for a sequela claim

Four elements have to appear in the record before S02.11CS is supportable. Miss one and the code is exposed at audit.

• Fracture type confirmed as Type II: the clinician or radiologist documents Type II by name. Wording that clearly maps to it also works, such as a basilar fracture extending into the right occipital condyle.
• Right-side laterality documented: the record names the right occipital condyle. An unspecified side sends you to S02.111S instead.
• Acute phase completion confirmed: the note shows the fracture has healed, or that the fracture itself no longer needs active treatment.
• Residual condition identified: a specific sequela is documented, such as chronic pain, a neurological deficit, or reduced cervical range of motion.

On the claim, the residual condition code comes first and S02.11CS follows as the cause. Accurate patient record documentation from the first visit cuts down on retrospective queries at payer review.

The residual condition is usually managed well away from the trauma unit. Teams working in sports medicine and physical therapy practices are frequently the ones documenting the deficit that makes S02.11CS reportable.

Approximate synonyms and index terms

These terms show up in the ICD-10-CM alphabetic index and in clinical documentation, and they all lead to S02.11CS. Confirm the final selection against the tabular list rather than the index alone.

• Type II occipital condyle fracture, right, late effect
• Fracture of occiput, Type II, right side, sequela
• Occipital condyle fracture, Anderson-Montesano Type II, right, residual
• Skull base fracture extending to right occipital condyle, sequela
• S02.11C sequela, right occipital condyle
• Right occipital condyle fracture, sequela encounter

EHR search tools surface these synonyms during code lookup. Standardizing the wording inside your note templates cuts down on lookup errors at the point of coding.

How Pabau supports documentation for fracture sequela coding

Most practices code a sequela claim from notes that were written for a different purpose. The fracture type sits in an imaging letter and the side is in a triage note. The residual symptom turns up somewhere in a free-text follow-up.

Pabau brings the clinical record, treatment notes, and billing into one system. You can build the sequela details into a consultation note template. Fracture type, side, and the residual condition then get captured as structured fields at the visit.

Every Pabau subscription includes the full platform, so records, notes, claims, and reporting all come as standard. Practice management software that keeps them together is what stops the coder chasing the clinician a week after the appointment.

Sequela coding built on a complete record

Pabau keeps fracture type, side, and the residual condition in one structured note. Your coder reads what they need from the record instead of chasing the clinician.

Book a demo

Conclusion

S02.11CS is a narrow code, and that is the point of it. Type, side, and phase of care are all baked into the seven characters. The code only holds up when the record states all three.

Get the documentation right at the visit and sequencing becomes the only thing left to watch. Get it wrong and you are rebuilding the story from memory when the denial lands, months later.

Book a demo to see how Pabau captures fracture type, side, and residual conditions in the note your coder works from.

Continue your research

Coding a skull fracture that is healing slowly? S02.81XG covers the delayed-healing extension on a base-of-skull fracture.

Need the cord-injury code that pairs with a craniocervical fracture? S14.119S covers a cervical spinal cord injury reported as a sequela.

Reporting an open fracture on the first encounter? S02.121B shows how the B extension works on an orbital fracture.

Working through subsequent-encounter rules? S43.014D applies the D extension to a shoulder dislocation follow-up.

Coding a fracture that healed in the wrong position? S49.029P covers the malunion extension, which the skull codes do not use.

Frequently asked questions