ICD code S82.461N – Displaced segmental fracture of shaft of right fibula

Key takeaways

S82.461N describes a displaced segmental fracture of the right fibular shaft that has failed to unite.

The 7th character N applies only when the original injury was an open fracture of Gustilo type IIIA, IIIB, or IIIC.

Character C covers the initial encounter for that same injury, while A and B belong to closed and type I or II fractures.

Nonunion needs a physician’s diagnosis in the record, not a radiology note saying that healing looks slow.

Use S82.463N when the documentation never names a side, and S82.462N for the left leg.

S82.461N is billable, specific, and current for 2026

The fields below are the ones a claim scrubber checks first, so it is worth reading them before the detail.

Every word in the S82.461N description does a job

The full description packs seven clinical facts into one line. Miss any of them and you land on a different 7th character, or a different subcategory.

• Displaced: The fragments have shifted out of normal alignment. That is what separates S82.461 from S82.464, the nondisplaced segmental fracture of the right leg. Both the note and the imaging report need to support displacement.
• Segmental: Two fracture lines have isolated a free segment of bone along the fibular shaft. It is mechanically different from a single transverse or oblique break. ICD-10-CM captures it at S82.46, separate from the other shaft patterns in S82.4.
• Shaft of fibula: The diaphysis, not the proximal or distal end. A fibular head, neck, or malleolar fracture belongs to another category entirely.
• Right leg: Laterality is mandatory here. The 6th character 1 sets the right leg. S82.462N is the left-leg equivalent, and S82.463N applies when the record never names a side.
• Subsequent encounter: The patient is under continuing care after the initial treatment episode. This is not the first visit for the injury.
• Open fracture type IIIA, IIIB, or IIIC: The original wound was high-energy, with the soft-tissue involvement the Gustilo-Anderson system grades as type III. ICD-10-CM puts all three subtypes in one character group.
• Nonunion: The fracture has failed to unite inside the expected healing window. That is a complication rather than slow recovery, and it takes its own character.

The 7th character is where S82.461N claims go wrong

N means one thing. It is a subsequent encounter for an open type IIIA, IIIB, or IIIC fracture that has not united.

Two facts pick it. The first is the Gustilo group recorded at the original injury, and the second is how the fracture has healed since. The grid below pairs them.

Here is the same set as a list, with the sequela character included.

Character N is one of three nonunion characters. K covers a closed fracture, M an open type I or II, and N an open type IIIA, IIIB, or IIIC.

So the original injury decides the character, not the visit in front of you. Reporting K on a fracture the index admission documented as open is the error auditors look for.

Gustilo type at the injury decides your character group

ICD-10-CM borrows the Gustilo-Anderson classification wholesale. The type recorded at the original injury fixes which characters stay available to you, and that decision follows the patient through every later encounter.

Notice that the 7th character does not separate IIIA, IIIB, and IIIC. All three take C at the initial encounter, then F, J, N, or R once healing declares itself.

The subtype still matters clinically and in the operative note. For the diagnosis code, though, the three behave as one group.

Nonunion is not slow healing, and payers know the difference

Three healing outcomes, three sets of characters. Mixing them up is the most common error on subsequent-encounter fracture claims, and it is easy to do when the note hedges.

Nonunion is a clinical diagnosis, not a radiology finding. The treating physician has to state that healing has stopped, with serial imaging behind the statement.

One study showing no callus will not carry it alone. Without that diagnosis in the record, S82.461N is a code the chart cannot defend.

Walk the hierarchy and the code assembles itself

S82.461N is built from the top down, one character at a time. Reading the chain in order is the quickest way to confirm you are in the right subcategory before you commit to a 7th character.

• S00-T88: injury, poisoning and certain other consequences of external causes
• S80-S89: injuries to the knee and lower leg
• S82: fracture of lower leg, including ankle
• S82.4: fracture of shaft of fibula
• S82.46: segmental fracture of shaft of fibula
• S82.461: displaced segmental fracture of shaft of fibula, right leg
• S82.461N: subsequent encounter, open fracture type IIIA, IIIB, or IIIC, nonunion

The sibling codes you will reach for next

S82.461 carries the whole encounter and healing series for one leg and one fracture pattern. The codes below are the ones coders genuinely confuse with N, either because the encounter changed or because the side was never documented.

Nondisplaced patterns run in parallel at S82.464 through S82.466, and the rest of the fibula sits outside S82.4 altogether. Our wider diagnostic code library is the place to pick up the neighboring categories.

What the record must say before you bill S82.461N

Six facts have to be in the chart. Miss one and the code can be perfectly chosen while the claim stays unsupportable.

• Laterality confirmed as right leg: the operative note, the imaging report, or the encounter note names the right fibula or the right lower leg.
• Segmental and displaced pattern: radiology and operative notes describe two fracture lines with a free fragment, and record the displacement.
• Gustilo type IIIA, IIIB, or IIIC at the original injury: the index admission note or operative report grades the wound. If it only says “open fracture”, you cannot assign character N.
• Encounter classified as subsequent: the visit is continuing management after definitive treatment. Emergency care for the original injury takes an initial character, which for this injury is C.
• Nonunion diagnosed by the treating physician: the note diagnoses nonunion rather than noting slow healing. Serial imaging findings and a statement that the fracture will not unite without intervention are what support it.
• External cause code where it applies: add a code from the V, W, X, or Y chapter to identify the mechanism. That matters most on work and transport injuries.

Templates help more than reminders do. An encounter note that prompts for Gustilo type and healing status at every visit does the work upfront. The chart is then complete before it reaches coding.

Coding rules, exclusions, and sequencing

S82.461N is a billable, specific code, valid for HIPAA-covered electronic transactions under the 2026 edition that took effect on October 1, 2025.

The CMS ICD-10 codes page is the primary reference. Five rules govern how the code behaves from there.

• Exclusion notes do apply: S82.4 carries an Excludes1 note for traumatic amputation of the lower leg (S88.-). Its Excludes2 notes cover fracture of the foot except the ankle (S92.-) and periprosthetic fracture (M97.1- and M97.2-). Read them before you pair S82.461N with a companion diagnosis.
• Use an additional code for external cause: the Official Guidelines invite an external cause code from V00-Y99 to show how the injury happened. The instruction is not mandatory, though some payer contracts require it on trauma claims.
• Sequencing: S82.461N usually sits as the principal or primary diagnosis when the encounter is about nonunion management. Companion codes for vascular complications or infection follow the sequencing rules published by CMS and the CDC ICD-10-CM web tool.
• Payer-specific coverage: local coverage determinations can limit which procedure codes a payer accepts next to a nonunion diagnosis. Check them before you bill revision surgery or bone grafting.
• Code history: S82.461N has been billable across several ICD-10-CM editions, and the 2026 cycle brought no change to it. You can confirm current validity in the AAPC code lookup.

Before you submit: Where the S82.461N claim stalls

The code is only the first stop. From the encounter note it moves onto the superbill, where it sits beside the procedure code. From there it leaves on the 837P claim file, gets screened by a clearinghouse, and meets the payer’s own edits.

Two of those stops reject on specificity rather than on medicine. A clearinghouse will catch an invalid character combination before the payer ever sees the claim. Payer edits are the harder ones, because a valid code can still fail a coverage rule attached to nonunion surgery.

Run this check before you submit

1. Open the index admission record and confirm it grades the wound as Gustilo type III.
2. Confirm the current note carries a nonunion diagnosis, not a comment about slow healing.
3. Confirm the side. Right leg is the 1 in S82.461, and an undocumented side sends you to S82.463N.
4. Confirm the encounter is subsequent, so the character is N rather than C.
5. Check the payer’s coverage rules for the procedure you are billing alongside the diagnosis.

Three mistakes that get S82.461N denied

• Reporting K because the note says nonunion and nobody checked whether the fracture was open.
• Carrying character C forward from the initial encounter into a follow-up visit.
• Sending nondisplaced S82.464N after the operative note describes displaced fragments.

Fracture codes do get rejected. A repeatable denial management workflow tells you whether the problem was the Gustilo documentation, the 7th character, or the payer’s coverage rule.

How Pabau keeps the code attached to the record behind it

A nonunion case usually crosses three systems. The note lives in the chart, the diagnosis gets keyed into a billing screen, and the claim leaves from a third tool. Every hand-off is another chance to type S82.462N when the chart says right leg.

Practice management software like Pabau keeps those steps on one record. The diagnosis code attaches to the treatment note, the invoice builds from the same record, and the claim goes out electronically through an integrated clearinghouse. Remittances and rejections land back in the same place.

The payoff for a billing team is narrow and repeatable. Nobody retypes a seven-character code, and the note supporting it sits one click from the claim. That is the point of connected claims management on cases that run across several encounters.

Keep the code and the claim on one record

Pabau links the diagnosis code to the treatment note, then sends the claim from that same record. Fewer hand-offs mean fewer retyped characters on complex fracture claims.

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Conclusion

S82.461N is a narrow code, and the narrowness is the point. It says right leg, segmental, displaced, open type III at the injury, and no union at this visit. If the chart cannot show all five, this is not the code to send.

So the habit worth building is small. Check the index admission before you pick the character, because that one look settles the closed-or-open question. It is where most nonunion claims lose their specificity.

Pabau keeps that record and the claim in one place, so the code a clinician documented is the code that goes out. Book a demo to see how a nonunion claim travels from note to payer without a retype.

Continue your research

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