Coding a subsequent fracture encounter means you must specify malunion or nonunion.

Cracking the code of a fracture: why healing status matters in a subsequent encounter

Fractures come with a lot of moving parts—bone fragments, healing timelines, imaging results, and a patient who’s navigating recovery. For those who translate medical scenes into codes, there’s a single line that often carries more weight than others when a patient returns for a follow-up visit: is the fracture healing as expected, or has it run into trouble? In ICD-10-CM coding, the primary requirement for a subsequent encounter focused on a fracture is to specify whether it is a malunion or a nonunion. Let me explain why this distinction is so pivotal and how it shows up in real-world coding.

What does “subsequent encounter” really mean?

Think of the care journey after the bone is first set. The initial encounter covers the moment of injury and the first treatment. The follow-up visit—when the patient returns for healing checks, hardware adjustments, cast changes, or additional imaging—falls into what coders call a subsequent encounter. At this stage, the emphasis shifts from “what happened” to “how the bone is healing.” That shift isn't just clinical; it’s financial and administrative too. It shapes the record, guides treatment decisions, and finally informs billing and continuity of care.

Malunion vs. nonunion: what your notes must capture

Here’s the core distinction in plain language:

• Malunion: the fracture has healed, but not in the correct position or alignment. The bone may be fused in a way that could cause ongoing weakness, deformity, or functional limitation. Recovery has occurred, but not in the ideal alignment.

• Nonunion: the fracture has not healed—there’s a persistent gap or movement in the bone, despite time and treatment. This status signals ongoing pathology and often calls for adjusted treatment plans, such as additional surgery or alternative immobilization.

Why this matters beyond the chart

You might wonder, “Sure, but why not just record the fracture site and call it a day?” The answer is simple: the healing status drives the next steps. If a fracture is malunited, surgeons and therapists may focus on restoring function and preventing future problems. If it’s nonunited, the care team might explore surgical revision, bone grafts, or hardware adjustments. Billing follows this logic too. Payers want to know whether the patient is in a stable healing phase or dealing with a complication that requires additional procedures, imaging, or longer care. In short, malunion and nonunion aren’t just medical terms; they’re decision-making signals that align medical necessity with reimbursement realities.

What to document to get it right

While all the usual fracture details (site, laterality, mechanism, exact fracture pattern) matter, the essential piece for a subsequent encounter is the healing status. A clean, explicit note like this supports precise coding:

• “Fracture of [bone and site], malunited, with subsequent encounter for fracture healing and planned follow-up imaging.”

• “Fracture of [bone and site], nonunion, with subsequent encounter for nonunion management and planned surgical consultation.”

A few practical tips to keep the documentation tight and useful:

• Use unmistakable terms: malunion and nonunion should be present in the encounter note. If a clinician uses different words (delayed union, nonhealing fracture, malpositioned healing), ask for clarifications or an addendum that anchors the terminology to healing status.

• Tie the status to observations: imaging results, clinical findings (pain levels, range of motion, weight-bearing status), and functional impact help justify the coding choice.

• Connect to the encounter type: note that this is a subsequent encounter, and briefly describe what was done at this visit (e.g., immobilization adjustments, imaging, or consults) to paint a complete picture for readers of the chart.

• Maintain consistency: once you identify malunion or nonunion, keep that status consistent across related encounters unless the healing trajectory changes and a new status is documented.

A quick mental model you can use

• Step 1: Identify the healing status. Is it on a healing track, or has healing stalled or gone wrong? The answer points you to malunion or nonunion.

• Step 2: Confirm this is a subsequent encounter. The patient is returning, not the initial injury event.

• Step 3: Document precisely. State the fracture site, the healing status, and the reason for the follow-up (assessment, treatment adjustment, planning, etc.).

• Step 4: Add any relevant follow-up actions. Will there be imaging, physical therapy, or a surgical consultation? This helps the care team stay coordinated and the record complete.

A few common-sense pitfalls to avoid

• Skipping the healing-status note: You’re tempting fate when you code for a subsequent encounter without stating whether the fracture is malunited or nonunited.

• Making assumptions: If the chart only says “fracture of [site], follow-up,” don’t infer healing status. Ask for confirmation and use precise terms.

• Inconsistent terminology: If one visit says malunion while another uses delayed union without clear linkage, seek clarification to keep the record coherent.

• Overlooking imaging results: The radiology report often seals the healing status. Don’t omit this essential clue from the coding narrative.

• Forgetting the continuity cue: The 7th-digit convention or another system cue that marks “subsequent encounter” should be reflected in the coding note so the record aligns with billing guidelines.

How this approach plays out in real life settings

Consider a patient who had a tibia fracture repaired with a plate. At a three-month follow-up, imaging shows the bone is healing, but the alignment isn’t perfect. The clinician classifies the case as a malunited fracture with a plan for continued follow-up and possible corrective surgery. In the chart, the coder documents: malunion, subsequent encounter for fracture healing, with plan for imaging in six weeks and surgical consultation as needed. That sentence neatly captures the key healing status, the encounter type, and the path forward. It’s a compact, accurate snapshot that supports clinical decisions and clean billing.

On the flip side, imagine a different patient with the same site and initial management, but imaging reveals no signs of healing after a period of treatment. The plan calls for a revision surgery. In the note, nonunion is stated clearly, followed by the plan for surgical intervention and follow-up imaging. Here again, the healing status is the star of the show, guiding both care and claims.

Why this approach isn’t just a rule, but a practice you can own

The world of coding isn’t about memorizing codes in isolation. It’s about communicating a patient’s story in a way that supports safe, effective care and fair reimbursement. The focus on whether a fracture is malunited or nonunited at a subsequent encounter reflects that broader aim: the status of healing directly influences what comes next. When you document clearly, you reduce ambiguity, improve care coordination, and help ensure that every bill matches the patient’s true clinical needs.

A friendly nudge toward sharper habits

If you’re new to this territory, here are a few easy routines that pay off:

• Create a standard note template that includes: fracture site, healing status (malunion/nonunion), encounter type (subsequent), imaging results, and agreed next steps.

• When in doubt, ask for a targeted clarification from the clinician—short notes that explain “why we’re seeing malunion” or “why nonunion is suspected” save everyone time.

• Review a few chart examples periodically. Seeing how different teams phrase healing status helps you spot nuances and keep your own notes precise.

A practical way to internalize the rule

Next time you review a fracture chart, practice this mental checklist:

• Is this a subsequent encounter? Yes? Then the healing status matters most.

• Have the terms malunion or nonunion been used? If not, how can you capture the status clearly from imaging or clinician notes?

• Is there a plan for follow-up actions? Could future visits hinge on adjusting the treatment path? Note that too.

• Does the record connect the clinical status to the patient’s ongoing care? If yes, you’ve captured the spirit of the encounter.

In the end, the rule is straightforward, but its impact is real. Specifying malunion or nonunion in a subsequent encounter creates a bridge between what happened, what’s happening now, and what comes next for the patient. It aligns clinical needs with the realities of care management and billing, and it keeps the patient’s journey coherent and safe.

If you’re curious about how this plays out in different bones or how other healing statuses are captured, you’ll find more examples in clinical notes and coding guidance. The key is to stay curious, ask precise questions, and let the healing status guide the sequence of documentation. When you do, you’ll find that the codes tell a story that’s accurate, actionable, and patient-centered.

So the next time a patient returns with a fracture, remember: the critical note to lock in is whether the fracture has malunited or nonunited. It’s the detail that makes the rest of the chart sing in harmony, and it’s the detail that helps everyone—from clinicians to coders to the people who handle claims—make the right path forward.