ICD-10 Code S62.291B: Other fracture of first metacarpal bone
S62.291B covers an open first metacarpal fracture of the right hand at the initi...
Last Updated: August 13, 2026
Key takeaways
S72.431R covers a displaced medial condyle fracture of the right femur at a subsequent encounter, for an open type III fracture with malunion.
The 7th character R means open fracture type IIIA, IIIB, or IIIC with malunion, so it never applies to a closed fracture.
Closed fracture malunion at the same site takes 7th character P, and open type I or II malunion takes Q.
The 6th character carries displacement and laterality together, so 1 through 3 are displaced and 4 through 6 are nondisplaced.
Pabau’s claims management tools attach ICD-10 codes inside the patient record, so the code on the claim matches the clinical note.
ICD-10 Code S72.431R is a billable ICD-10-CM diagnosis code for a displaced fracture of the medial condyle of the right femur. It applies at a subsequent encounter, once an open fracture of type IIIA, IIIB, or IIIC has healed with malunion.
The open fracture requirement is where this code is most often misapplied. Coders reach for R whenever the record says malunion, but closed fracture malunion belongs to character P instead. This reference covers the code hierarchy, the full 7th character set, sibling codes, documentation requirements, and the ICD-9 crosswalk.
ICD-10 Code S72.431R: definition, billable status, and 2026 validity
ICD-10 Code S72.431R is a billable and specific ICD-10-CM diagnosis code. The CDC/NCHS ICD-10-CM web tool confirms it is valid for the 2026 code set, effective October 1, 2025. It maps to one well-defined clinical scenario, so payers accept it directly on claims.
The CMS ICD-10-CM/PCS code files maintain the official tabular list and coding guidelines for this code family. Verify current-year validity before applying any S72 code to a claim, because additions and revisions land with each October update.
Code hierarchy: parent codes for S72.431R
S72.431R sits at the bottom of a four-level hierarchy within the fracture of lower end of femur classification. The parent chain matters for correct specificity, and for choosing among sibling codes when laterality or fracture type differs.
The S72 category covers every femur fracture, from femoral neck injuries at the proximal end to the distal condylar fractures in S72.4. That subcategory groups the medial condyle, the lateral condyle, and the supracondylar regions. S72.43 narrows to the medial condyle alone.
The 6th character then carries displacement and laterality together. Characters 1, 2, and 3 are displaced right, left, and unspecified femur. Characters 4, 5, and 6 are the nondisplaced equivalents. Sibling code S72.451K shows the same pattern applied to the supracondylar region.
Understanding the 7th character R: open fracture type III with malunion
The 7th character is where most S72 coding errors originate. It encodes three clinical determinations at once. Those are the encounter type, the fracture closure status, and the healing status. All three must be documented in the record before S72.431R can be applied.
Malunion vs. nonunion: Malunion means the fracture united, but with angular, rotational, or shortening deformity. Nonunion means it failed to heal within a reasonable period. For an open type III injury, malunion takes the R character and nonunion takes the N character. The ulna guide at S52.262K works through the same distinction in the forearm.
Swapping these two characters is a documented coding error that creates audit risk. Confirm that the attending provider has recorded which healing outcome applies before assigning either one.
Clinical meaning: displaced fracture of the medial condyle of the right femur
The medial condyle is the rounded bony prominence on the inner aspect of the distal femur, forming part of the knee joint. Fractures here usually follow high-energy trauma such as motor vehicle collisions or falls from height. Orthopedic surgeons and sports medicine clinicians see this pattern most often.
- Displaced: The fracture fragments have moved out of normal anatomical position. Displacement and laterality share the 6th character, so 1 is displaced right and 4 is nondisplaced right. Displaced condylar fractures generally require surgical fixation.
- Medial condyle: The site on the inner side of the distal femur. Lateral condyle fractures are coded under S72.42x, and unspecified condyle fractures under S72.41x.
- Right femur: Right is S72.431, left is S72.432, and unspecified is S72.433. Laterality must come from the provider, not from the coder.
- Open type IIIA, IIIB, or IIIC: The original injury broke the skin and carried extensive soft tissue damage under the Gustilo-Anderson classification. Type I and type II open fractures use different 7th characters.
- Subsequent encounter: The patient is in follow-up care after active treatment of the acute fracture. The active treatment phase for this injury uses 7th character C.
Related ICD-10 codes for medial condyle femur fractures
Patients move through several sibling codes across an episode of care, as the encounter type and healing status change. The table below lists the codes most often confused with S72.431R. The initial encounter code S72.431C is where the same episode usually starts.
Use S72.433R for an unspecified femur only when the record genuinely does not state a side. Laterality must come from the provider’s documentation rather than the coder’s assumption. Coding “unspecified” when the provider documented right or left is a specificity error that can trigger a claim edit.
Documentation requirements for ICD-10 Code S72.431R
Applying this code correctly requires the medical record to support six clinical facts. If any one of them is absent, a different code or a provider query is warranted. A structured patient record system with encounter-type and fracture-status fields keeps those details in one place.
- Fracture site confirmed: The documentation names the medial condyle of the femur. If the record says only “condylar fracture” without stating medial or lateral, query the provider.
- Right side specified: The provider explicitly documents the right femur. If only “femur” appears, use S72.433R and consider a query for clarification.
- Displaced fracture type: The provider documents displacement. Nondisplaced fractures of the same condyle use S72.434, S72.435, and S72.436 instead.
- Open type III confirmed: The 7th character R applies only to open fractures graded IIIA, IIIB, or IIIC. A closed fracture takes P, and an open type I or II fracture takes Q.
- Subsequent encounter status: The visit is follow-up care after active treatment, not the initial emergency or surgical encounter.
- Malunion clinically established: The provider documents malunion, ideally with imaging that shows angular, rotational, or shortening deformity. Digital clinical documentation forms with a healing-status field help teams capture this consistently.
Pro Tip
Audit your S72 subsequent encounter codes each quarter. Pull every claim where a routine-healing character was billed more than six months after the initial encounter date. By that point the record should describe the fracture as healed, malunited, or nonunited. Routine-healing claims past the expected window are a common audit trigger.
ICD-9-CM to ICD-10-CM crosswalk: S72.431R and code 733.81
For practices holding legacy billing data or answering audits on historical claims, the ICD-9-CM equivalent of S72.431R is 733.81. The mapping is approximate. The AAPC’s ICD-10-CM code lookup and the official General Equivalence Mappings from CMS and NCHS are the authoritative references.
ICD-9-CM 733.81 was a broad malunion code that maps to many S72 malunion codes in ICD-10-CM. That one-to-many relationship means it does not convert cleanly to a single successor. Translating legacy data therefore needs the original clinical record, not just the forward-mapping file.
The site, laterality, and open fracture grade all have to come from somewhere. Always check crosswalk results against the official GEM files rather than commercial conversion tables.
Coding guidelines and common errors when using ICD-10 Code S72.431R
Reference sites list the code but rarely explain where billers go wrong. These are the errors that surface most often in orthopedic coding audits for this family. The WHO’s ICD-10 classification framework and the CMS official coding guidelines supply the underlying rules.
- Treating R as the closed fracture malunion code: This is the single most frequent error on S72.431R claims. R is reserved for open type IIIA, IIIB, and IIIC injuries. Closed fracture malunion takes P.
- Skipping the Gustilo grade: Open type I and II injuries take Q rather than the R character. Request the grade from the operative or emergency record before you assign a subsequent encounter character.
- Confusing initial and subsequent encounters: Using C at a follow-up visit is common. Once active treatment ends and the patient is in routine aftercare, an F, J, N, R, or S character applies instead.
- Confusing malunion with nonunion: N means the fracture failed to heal, while R means it healed out of alignment. These carry different corrective CPT codes, so a mismatch creates a diagnostic-procedural conflict.
- Laterality left unspecified: Choosing S72.433R when the record documents a side is a specificity deficiency. Payers may still pay the claim, but the record loses clinical accuracy and can fail an audit.
- Omitting the cause-of-injury code: ICD-10-CM guidelines expect an external cause code for traumatic fractures. S72.431R captures the site and healing status, not the mechanism, so add a code from the V00-Y99 range where payer rules require it.
Most of these errors are caught at the point of documentation rather than at submission. An EHR integration workflow that carries the diagnosis code straight into claim generation removes the transcription step where they usually appear.
Pro Tip
Record the Gustilo-Anderson grade of the original fracture at the initial encounter. If a patient transfers into your care mid-treatment and the grade is unclear, request the surgical or emergency records first. The open versus closed distinction drives every subsequent encounter character in the episode.
How Pabau supports ICD-10 coding and claim accuracy
Today the coder looks S72.431R up on a reference site, then retypes it into a separate billing system. That handoff is where a 7th character quietly turns into the wrong one, and where the claim stops matching the note behind it.
Practice management software like Pabau removes the retyping step. Practitioners search for and attach the diagnosis code inside the patient record at the point of care. The code then flows into the claim unchanged, so laterality and 7th character errors have nowhere to enter.
Orthopedic, sports medicine, and rehabilitation teams often track fracture cases across many encounters. For them, physical therapy EMR software keeps the episode record consistent from the initial encounter through discharge. Pabau’s claims management tools then surface the attached code next to the clinical note, so you can confirm it matches what the provider documented.
Keep ICD-10 codes and clinical notes in step
Pabau attaches diagnosis codes inside the patient record and carries them through to claim submission without re-keying. That keeps encounter type, laterality, and healing status consistent across every visit in a fracture episode.
Conclusion
S72.431R rewards one habit above all others: reading the 7th character definition in full before you assign it. The letter looks like a generic malunion marker, and it is not. It commits the claim to an open type III injury that the original operative record has to support.
Practices that capture the Gustilo grade, the side, and the healing status at the point of care rarely have to revisit this code. Those that treat coding as a step after documentation end up choosing between P, Q, and R from an incomplete note. The correction costs far more than the original query would have.
An integrated practice management platform keeps that decision inside the clinical record instead of a separate lookup. Book a demo to see how Pabau keeps fracture coding accurate across every encounter in an episode.
Continue your research
Coding another subsequent encounter injury? S21.439D walks through the same 7th character logic for a thoracic puncture wound.
Billing the surgical side of fracture care? CPT code 20938 covers structural autograft documentation and the modifiers that go with it.
Documenting ligament findings alongside a fracture? Eversion stress test explains how to perform the maneuver and record the findings defensibly.
Assessing limb length after malunion? Supine to long sit test shows how clinicians screen for apparent leg length discrepancy.
Frequently asked questions
What does ICD-10 Code S72.431R mean?
ICD-10 Code S72.431R is a billable ICD-10-CM diagnosis code for a displaced fracture of the medial condyle of the right femur. It applies at a subsequent encounter, once an open fracture of type IIIA, IIIB, or IIIC has healed with malunion. The bone has united out of correct anatomical alignment.
Is S72.431R a billable ICD-10-CM code?
Yes. S72.431R is a billable and specific ICD-10-CM code, valid for the 2026 code set. Payers accept it directly on claims, and no further character is needed beneath it.
Does S72.431R apply to a closed fracture?
No. The 7th character R is reserved for open fractures graded IIIA, IIIB, or IIIC. Malunion of a closed fracture at the same site takes character P instead. An open type I or II fracture with malunion takes character Q instead. Assigning R to a closed fracture is the most common error on this code.
What is the difference between S72.431C, S72.431F, and S72.431R?
All three describe a displaced open type III fracture of the medial condyle of the right femur, and only the 7th character differs. C is the initial encounter, F is a subsequent encounter with routine healing, and R is a subsequent encounter where the fracture healed with malunion. The encounter type and the documented healing status decide which applies.
What does malunion mean in fracture coding?
Malunion means the bone healed, but with angular, rotational, or length deformity instead of correct alignment. It is distinct from nonunion, where the fracture failed to unite at all. For this code family, malunion takes P, Q, or R depending on the open fracture grade, while nonunion takes K, M, or N.
What documentation is required to use ICD-10 Code S72.431R?
The record must show a displaced fracture at the medial condyle of the right femur, graded as an open type IIIA, IIIB, or IIIC injury. It must also show that the visit is a subsequent encounter, with provider-documented malunion. If any element is missing, assign a different code or query the provider first.
