ICD-10 code S82.863D: Maisonneuve fracture, subsequent encounter

Key takeaways

ICD-10 code S82.863D describes a displaced Maisonneuve’s fracture of unspecified leg at a subsequent encounter for a closed fracture with routine healing.

The 7th character ‘D’ is required for every follow-up visit after initial treatment, and using ‘A’ on a return visit triggers claim denials.

S82.863 without a 7th character is not billable, so append the correct encounter suffix before you submit the claim.

Malunion of a closed Maisonneuve fracture takes the 7th character ‘P’, not ‘M’, which belongs to open fractures with nonunion.

Practice management software like Pabau keeps displacement status, laterality, and encounter type in the note at the point of care.

ICD-10 code S82.863D specifies a displaced Maisonneuve’s fracture of unspecified leg, at a subsequent encounter for a closed fracture with routine healing. This guide covers the code breakdown, every 7th character variant, the documentation payers expect, and the errors that get S82.863D claims denied.

S82.863D is valid for FY2026, effective October 1, 2025, per the CMS ICD-10-CM annual update. It sits within the S82 category, fracture of lower leg. The claim needs documented displacement status, laterality, and healing progression behind it.

ICD-10 code S82.863D: Quick reference

Use this reference card to confirm the code before attaching it to a claim. The S82 fracture category requires all seven characters before the code becomes billable, so a six-character version will not pass a payer’s edits.

What is a Maisonneuve fracture?

A Maisonneuve fracture is a proximal fibula fracture caused by an external rotation force at the ankle. Three structures are involved in the injury pattern:

• The proximal fibula, which carries the fracture itself
• The interosseous membrane, which tears longitudinally
• The medial ankle, with a deltoid ligament rupture or a medial malleolus fracture

That combination makes it an unstable ankle injury, even though the fracture sits well away from the ankle joint.

Clinically, the fracture is easy to miss. Patients present with ankle pain and swelling, but ankle-focused X-rays look normal because the fibula fracture sits at the proximal end. Full-length leg X-rays or MRI are needed for diagnosis.

That anatomy has a direct consequence for coders. The code must state displacement status and laterality, not simply “fibula fracture.”

• Displaced: fracture fragments are separated or angulated (S82.861, S82.862, S82.863)
• Non-displaced: fragments remain aligned (S82.864, S82.865, S82.866)
• Laterality: right leg (S82.861x), left leg (S82.862x), unspecified (S82.863x)
• Encounter type: determined by the 7th character (A, D, G, K, P, S)

According to the CDC/NCHS ICD-10-CM official tool, Maisonneuve fractures are indexed under S82.8, other fractures of lower leg. They do not sit with the ankle-specific codes, so searching “ankle fracture” in a lookup rarely surfaces S82.86x.

Full code description and classification

Each segment of ICD-10 code S82.863D carries clinical meaning. Understanding the hierarchy helps coders select the correct variant quickly and avoid non-specific parent codes.

S82.863 without a 7th character is not a billable code. The AAPC ICD-10-CM code reference flags the non-extended code as non-specific, and payers will reject claims submitted with it. Every claim must include the full seven-character code.

Understanding the 7th character: Fracture encounter types

The 7th character in S82.863x is where most coding errors occur. Payers use this character to verify that the services billed match the expected stage of fracture care. Mismatching the encounter type is the single most common reason ICD-10 code S82.863D claims are rejected.

The distinction between D (routine healing) and G (delayed healing) matters for reimbursement and clinical documentation. Routine healing means the fracture is progressing as expected for a closed Maisonneuve fracture. If healing is slower than the expected timeline without reaching nonunion criteria, G is correct.

Switching from D to G mid-treatment requires updated clinical notes reflecting the change in healing status. Every character above assumes a closed fracture. An open Maisonneuve fracture draws from a separate set, so the letter depends on healing status and on whether the skin was broken.

Related codes: S82.863 variants and laterality

When laterality is documented in the clinical note, coders should use the laterality-specific codes rather than the unspecified leg code. Using an unspecified code when the chart states right or left leg is an inaccuracy that can trigger audits. Our ICD-10-CM code reference carries the rest of the S82 family if you need to cross-check a variant.

The rule is the same across every diagnostic category. The most specific code the clinical documentation supports is the correct one. Defaulting to unspecified leg when the note names a side is inaccurate, and it invites an audit.

When to use S82.863D: Subsequent encounter for closed fracture with routine healing

ICD-10 code S82.863D applies to follow-up care during normal fracture healing. Knowing when to use it, and when not to, prevents the most common billing errors on Maisonneuve fracture claims. Practices treating musculoskeletal injuries need a documented healing status at every encounter, or the D character is unsupported.

Use S82.863D when:

• The patient is returning after initial treatment of a closed displaced Maisonneuve fracture
• The visit involves cast changes, wound checks, or splint adjustments
• The patient is being referred to physical therapy during the healing phase
• Radiographic or clinical assessment confirms healing is progressing as expected
• The fracture was treated non-operatively and healing is on track

Do NOT use S82.863D when:

• This is the first treatment encounter – use S82.863A instead
• Healing is delayed beyond the expected timeline – use S82.863G
• The fracture has failed to heal (nonunion) – use S82.863K
• The fracture healed in a malposition – use S82.863P
• The patient is presenting for a late effect of the healed fracture – use S82.863S
• Laterality is documented – use S82.861D (right) or S82.862D (left)
• The fracture is non-displaced – use S82.864D, S82.865D, or S82.866D as appropriate

Documentation requirements for S82.863D

The clinical note must support every element of ICD-10 code S82.863D. Auditors and payers check for specificity. If the note leaves out displacement status or healing progression, the code cannot be defended on review.

Coding guidelines and compliance notes

The ICD-10-CM Official Guidelines for Coding and Reporting govern how fracture codes in the S category are assigned. Applying them at the point of coding is cheaper than denial management after the fact, especially on musculoskeletal codes that carry audit risk.

• Subsequent encounter applies after the patient receives active treatment elsewhere. If another provider treated the fracture initially, D is still correct for your follow-up visit. That holds even when it is the patient’s first visit to your practice.
• Active treatment ends when the fracture reaches healed status. Once the patient has a healed fracture with residual effects, the sequela suffix (S) applies, not D.
• The 7th character must match the fracture type. S82.863D is specific to closed fractures. An open Maisonneuve fracture takes B or C at the initial encounter. Later encounters use E/F for routine healing, H/J for delayed healing, M/N for nonunion, and Q/R for malunion. Which letter of each pair applies depends on the Gustilo type. So M never applies to a closed fracture, where malunion is P.
• Multiple codes may be required. Maisonneuve fractures often involve concurrent medial ankle injuries. A separate code for a medial malleolus fracture or deltoid ligament rupture may be needed alongside S82.863D, per ICD-10-CM guidelines for multiple traumatic injuries.
• Laterality defaulting is not acceptable when documented. The ICD-10-CM guideline states that the most specific code supported by documentation must be used. Using S82.863D when the note says “right leg” is a coding inaccuracy.

Remittance advice is where 7th character errors show up first. Fracture-claim denials commonly cite an incorrect encounter type, so reviewing the remit codes each month catches a systematic mistake before it becomes a pattern.

How Pabau simplifies ICD-10 code management

Selecting the right ICD-10 code at the point of care is harder than it sounds when a clinician is working a full appointment schedule. The correct Maisonneuve code depends on displacement status, laterality, encounter type, and healing status. All four have to be in the clinical note before a coder ever sees it.

Practice management software like Pabau puts ICD-10 search inside the patient record. Clinicians attach the diagnosis code while the encounter is still in front of them. That removes the lag between documentation and coding that produces most 7th character errors.

Pabau’s automated claims management validates ICD-10 codes against the current FY2026 code set before submission. A claim carrying a non-billable parent code, like S82.863 without its 7th character, is flagged before it reaches the payer.

Claims then go out electronically through Claim.MD, Pabau’s US clearinghouse partner, which reaches more than 4,000 US payers. Each submission carries real-time eligibility checks and electronic remittance advice. A coder can also pull up the patient’s encounter history from the record, so the initial visit is easy to identify.

See how Pabau handles ICD-10 code management

Pabau embeds ICD-10 code search in the clinical workflow, validates codes before submission, and processes claims through Claim.MD across 4,000+ US payers. See it working in a live demo.

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Conclusion

Three checks settle S82.863D on almost every claim. Confirm the fracture is displaced, then confirm the encounter is a follow-up during routine healing. Use a laterality-specific code whenever the chart names a side.

The 7th character carries the payer’s signal that active treatment has ended and routine follow-up has begun. Treat it as a clinical statement, and the D-versus-P question answers itself from the healing status in the note.

If your team keeps seeing S82.86x denials, the cause is almost always a 7th character mismatch. The fix sits at the point of documentation. Book a demo to see how Pabau ties ICD-10 selection to the clinical note and validates the code before the claim goes out.

Continue your research

Need a reference for related musculoskeletal billing codes? Denial codes in medical billing explains the most common payer rejection reasons and how to resolve them.

Want to understand how clearinghouses process fracture claims? Claim.MD clearinghouse guide covers how electronic claim submissions work across major US payers.

Looking for broader ICD-10 documentation guidance? Medical billing compliance covers audit-readiness requirements for diagnosis coding across specialties.

Frequently asked questions