ICD-10 code S32.462B: Open left acetabular fracture coding

Key takeaways

ICD-10 code S32.462B is a billable code for a displaced associated transverse-posterior fracture of the left acetabulum, initial encounter for open fracture.

The parent code S32.462 cannot be billed on its own, because every S32.4 code needs a 7th character.

The 7th character B applies for the whole active treatment period, not only the first visit.

The only Excludes1 under S32 is transection of abdomen, so a documented hip fracture can share the claim.

Practice management software like Pabau keeps laterality, wound status, and treatment phase in the record the coder reads.

ICD-10 code S32.462B is a billable code for a displaced associated transverse-posterior fracture of the left acetabulum, initial encounter for open fracture. It sits in subcategory S32.46, which covers combined transverse and posterior acetabular patterns. The 7th character B marks the fracture as open while active treatment continues.

This reference covers the code description, the 7th character options, the sibling codes worth ruling out, the Excludes notes, and the documentation each element needs.

ICD-10 code S32.462B: Definition, billable status, and effective date

S32.462B is a billable and specific ICD-10-CM code. It is valid for FY2026, effective October 1, 2025. Coders can use it directly on claims, because no more specific child code exists below it.

The classification itself is maintained by the National Center for Health Statistics at the CDC. You can confirm the annual code set through the CMS ICD-10 code files. HIPAA requires covered entities to use ICD-10-CM for all diagnosis reporting.

Code description breakdown: What each component means

Every word in the S32.462B description carries coding weight. Misreading any one component sends you to the wrong code.

• Displaced: The fracture fragments have moved out of normal alignment. Displacement is an explicit coded attribute here, not an assumption. Nondisplaced left-side patterns take S32.465 instead.
• Associated: The injury combines two patterns rather than one. A transverse element and a posterior column or wall component occur together.
• Transverse-posterior: A fracture morphology in the Letournel classification. A transverse line crosses the acetabulum, and a posterior column or wall component sits alongside it. Femoral head dislocation often accompanies the injury, although the official code title does not name it.
• Acetabulum: The cup-shaped socket that holds the femoral head and forms the hip joint. These fractures are high-energy injuries, usually from motor vehicle collisions or falls from height.
• Left: Laterality is explicit in S32.462. Left is S32.462x, right is S32.461x, and unspecified is S32.463x.
• Initial encounter: The patient is receiving active treatment. This covers the first visit and every visit after it while active treatment continues.
• Open fracture: A wound connects the fracture site to the outside environment. The closed equivalent is S32.462A.

Clinical anatomy of the acetabulum and transverse-posterior fractures

The acetabulum forms the hip socket, where the ilium, ischium, and pubis meet at the triradiate cartilage. It is divided into an anterior and a posterior column. Together those columns form an inverted Y that supports the femoral head.

Transverse-posterior fractures are among the more complex Letournel patterns. The transverse component cuts across both columns, splitting the acetabulum into superior and inferior segments. A posterior wall or column fracture then sits on top of that split.

The combined pattern is what separates S32.46 from its neighbors. A pure transverse fracture codes to S32.45x. An isolated posterior wall fracture codes to S32.42x, not S32.41x, which covers the anterior wall.

Rehab notes decide when the encounter type changes. Practices running physical therapy documentation or occupational therapy software should record the date the surgeon signs off on active treatment.

7th character extensions for S32.462: Choosing the right suffix

S32.462 needs a 7th character before it can be billed. Category S32 offers six, and there is no malunion character in this family. Picking the wrong one is the most common reason these claims fail.

The same K character marks nonunion across other fracture families. S82.232M applies the equivalent logic to a tibial shaft.

When to use S32.462B: Open fracture at initial encounter

Use S32.462B when the operative or emergency report documents an open fracture. Under the ICD-10-CM Official Guidelines, Section I.C.19, the 7th character B applies when bone or fracture hematoma communicates with the outside environment through a wound.

The initial encounter designation runs for the whole active treatment period, which may span several visits. Picture a patient seen in the ED, taken for open reduction internal fixation, then back a week later for a wound check. If the surgeon is still managing the fracture, the encounter is still initial.

Move to D, G, or K only once active treatment has ended and the patient enters the healing or monitoring phase.

S32.462A vs S32.462B vs S32.462D: Key differences

These three codes cause most of the confusion. A and B differ on wound status. B and D differ on encounter phase.

• S32.462A, closed and initial: Use when no wound communicates with the fracture. This is the usual presentation for fractures managed without an open approach.
• S32.462B, open and initial: Use when the operative or ER record confirms an open or compound wound. It affects DRG assignment and signals higher-acuity inpatient management.
• S32.462D, routine healing and subsequent: Use for follow-up visits after active treatment ends and the fracture is healing normally. Switching here too early is a compliance risk.

Code hierarchy: S32.4 to S32.462B

Knowing where S32.462B sits explains why S32.462 cannot stand on its own. Each level adds clinical specificity. S32 also sits beside S33, which covers dislocations and sprains of the lumbar spine and pelvis, including S33.140A.

Sibling and parent codes worth ruling out

Choosing S32.462B correctly means ruling out its neighbors first. The differentiators are laterality, displacement status, and fracture pattern.

Descriptions and billable status change with each annual update. Check the current entry in an ICD-10-CM code lookup before you submit.

Excludes1 and Excludes2 notes for S32.462B

Excludes notes decide what can share a claim with S32.462B. Category S32 carries one note of each type, and coders routinely swap them around.

Excludes1, never coded together. An Excludes1 note means the two conditions cannot coexist in the same patient. Category S32 lists a single entry:

• Transection of abdomen, coded to S38.3

Excludes2, may be coded together. An Excludes2 note means the condition is not part of S32, but both may be reported when both are documented. Category S32 again lists a single entry:

• Fracture of hip NOS, coded to S72.0-

That second note matters more than it looks. A documented femoral neck fracture does not block S32.462B. Report both codes when the record supports each injury separately.

The Excludes1 and Excludes2 conventions themselves are set in the ICD-10-CM Official Guidelines, Section I.A.12. The AHA Coding Clinic adds quarterly case-specific guidance on the harder pairings.

Sequencing and encounter rules for fracture codes

Section I.C.19 of the ICD-10-CM Official Guidelines governs fracture coding. It defines the encounter types behind characters A and B, D, G and K, and S. Those definitions are stricter than their plain-English meanings suggest.

The CDC ICD-10-CM web tool is the official US lookup source for the current code set.

• Initial encounter, A or B: The patient is receiving active treatment. That covers emergency care, surgery, evaluation by a new physician, and post-operative care while the surgeon still manages the fracture. For complex open acetabular fractures, this phase can run for months.
• Subsequent encounter, D, G, or K: Active treatment has finished and the patient is in the healing, monitoring, or complication phase. Routine follow-up after ORIF belongs here, once the surgical team has signed off.
• Sequela, S: The acute injury has resolved but left a residual condition, such as post-traumatic hip arthritis. Report the residual condition first and S32.462S second.
• External cause codes: Sequence S32.462B first. Codes from V00-Y99 are added afterwards to capture the mechanism and place of occurrence. An external cause code is never sequenced first.

When more than one fracture is present, the UHDDS principal diagnosis rules decide which injury leads the claim.

Documentation requirements for a clean S32.462B claim

S32.462B cannot be coded from a thin record. Every component of the description needs support from physician or operative documentation. Miss one and the coder has to drop to a less specific code, which can change the DRG.

That has a direct effect on payment, which is where Medicare billing rules bite hardest. Keeping HIPAA-compliant documentation in orthopedic trauma means capturing every element the code requires, not just the diagnosis name.

Structured operative note templates and digital intake forms close those holes at the source, before a claim is ever generated. Building the same prompts into your clinical documentation workflows keeps trauma intake consistent across the team.

Common coding errors and how to avoid them

Most S32.462B claim errors trace back to one of five mistakes. Knowing where coders go wrong is the fastest way to stop repeating it.

• Submitting the parent code S32.462: It has no 7th character, so payers reject it as incomplete. Always add the suffix before billing.
• Using A when B is required: If the note describes an open fracture, the code is S32.462B. The same applies when it documents debridement of a wound communicating with the fracture site. Choosing A understates acuity and creates a compliance risk.
• Switching to a subsequent character too early: Many coders move to D after the first post-operative visit. The Guidelines do not support that. The patient stays in the initial phase while the surgeon actively manages the fracture.
• Getting laterality wrong: S32.462B is left-side specific. A right-side injury codes to S32.461B. When laterality is missing, use S32.463B and query the physician. There is no S32.469 code.
• Confusing the combined pattern with isolated ones: S32.462B needs the associated pattern. A pure transverse fracture codes to S32.45x, and an isolated posterior wall fracture codes to S32.42x. Documentation has to name the pattern.

The AAPC Codify lookup lets you confirm that the code you picked is the most specific one available for what the record says.

How Pabau keeps fracture documentation coder-ready

In most orthopedic practices the coder has to go hunting. Laterality sits in the operative note, wound status in the ER chart, and the treatment plan somewhere else again. By the time all three are found, the claim is already late.

Pabau keeps that detail in one place. Structured treatment notes and digital consent forms capture displacement, laterality, and wound status at the point of care. Pabau’s patient records then hold those notes against the same file your biller opens.

From there, claims management pulls what is already on the record into a pre-filled claim, then submits and tracks it. Nothing gets retyped, so a documented open left acetabular fracture stays that way all the way to the payer.

The outcome is fewer physician queries, fewer denials caused by a missing word, and a record that still reads clearly two years later at audit.

Keep trauma documentation coder-ready from day one

Pabau’s structured treatment notes and digital forms capture laterality, wound status, and treatment phase at the point of care. Book a demo to see how the record reaches your biller intact.

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Conclusion

S32.462B is not a difficult code to assign. It is a difficult code to defend when the record is thin. The five elements it depends on are all things a surgeon says out loud in theater and then forgets to dictate.

So query before the claim goes out, not after the denial arrives. And read the Excludes notes in the right direction. A concurrent hip fracture is an Excludes2, which means it belongs on the claim rather than off it.

For practices handling high-acuity orthopedic work, Pabau’s practice management software keeps the documentation structured enough to survive an audit. Book a demo to see how it fits your coding process.

Continue your research

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Want your trauma records to hold up at audit? HIPAA compliance for medical offices sets out the data security and record-keeping standards.

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