ICD-10 Code S92.145K: nondisplaced dome fracture of left talus

Key takeaways

ICD-10 Code S92.145K describes a nondisplaced dome fracture of the left talus at a subsequent encounter with confirmed nonunion.

The 7th character K designates fractures that have failed to heal within the expected timeframe. It is distinct from G for delayed healing and S for sequela.

Documentation must confirm laterality, displacement status, dome morphology, and nonunion in the clinical notes before this code can be assigned.

S92 codes use a short seven-character set, so nonunion always takes K whether the original fracture was open or closed.

Practice management software like Pabau keeps the physician note, imaging, and diagnosis code on one patient record, then submits and tracks the claim.

ICD-10 Code S92.145K is a billable code for a nondisplaced dome fracture of the left talus at a subsequent encounter with nonunion. It applies once the treating physician documents that the fracture has failed to heal.

This reference covers the official description, the 7th character set for talus fractures, the full S92.145 family, documentation requirements, and billing guidance. All code details follow the ICD-10-CM classification maintained by the National Center for Health Statistics at the CDC. Claim submission rules follow CMS coding guidance.

ICD-10 Code S92.145K: definition and billable status

Full description: Nondisplaced dome fracture of left talus, subsequent encounter for fracture with nonunion.

The code is billable and claim-specific, so it can be submitted on CMS-1500 and UB-04 claim forms. It sits in category S92 for fractures of the foot and toe, inside block S90-S99 for ankle and foot injuries. That block belongs to the S00-T88 injury chapter of ICD-10-CM.

What is a nondisplaced dome fracture of the talus?

A dome fracture is a break in the upper articular surface of the talus, the part that meets the tibia. Nondisplaced means the fragments have stayed in alignment.

The talus is the ankle’s load-bearing keystone. It sits where the tibia, fibula, and calcaneus meet, and it carries body weight across the foot. Dome fractures usually come from axial loading plus rotational force, most often in ankle sprains, falls from height, or sports impacts.

• Nondisplaced: the fragments stay anatomically aligned. The bone has cracked but the edges have not separated. That changes both treatment planning and code selection.
• Displaced: the fragments have shifted out of position. Displaced dome fractures take a different S92 subcategory.
• Laterality: S92.145K specifies the left talus, and the right-side equivalent is S92.144K. Confirm the side in the clinical documentation first.

Coders and clinicians often check the Ottawa ankle rules to see when imaging is indicated. Nonunion is where the coding gets decided. Orthopedic literature generally puts the threshold at 6 to 9 months with no radiographic sign of bridging callus.

Past that point, and with physician confirmation, the 7th character K becomes correct. Clinicians working in sports medicine and musculoskeletal rehabilitation see talar nonunion most often in athletes whose fracture was missed or diagnosed late.

What the 7th character K means

The 7th character K marks a subsequent encounter where the fracture has failed to heal. Every fracture code in category S92 needs a 7th character, and that character carries two pieces of information at once. It records the encounter type and, for subsequent encounters, the healing status.

Parent code S92.145 covers nondisplaced dome fracture of the left talus across all encounter types. Choosing the 7th character is the step coders most often get wrong, especially between delayed healing and confirmed nonunion.

S92 fractures take a short set of seven characters. The set runs A, B, D, G, K, P, and S, and B is the only open-fracture character. Unlike lower-leg codes such as S82.291J, S92 codes do not split subsequent encounters by open-fracture type. So a talar dome nonunion always takes K, whether the original injury was open or closed.

K versus G is the distinction that matters. G applies when the fracture is healing, only slower than expected. K applies when the physician has documented that healing has failed. A coder cannot assign K on elapsed time alone, so the physician must state nonunion in the notes. ResDAC ICD code guidance explains how these distinctions show up in claims data.

Related codes in the S92.145 family

The table below shows the full S92.145 family, plus the right-side and unspecified equivalents and the displaced counterpart. The rest of the tarsal fracture codes follow the same encounter pattern, as S92.209K shows.

Check every code against the CDC ICD-10-CM tool for the current fiscal year before you submit. Code validity and descriptions are updated annually.

Documentation requirements for S92.145K

Nonunion is a physician-determined diagnosis. A coder cannot assign S92.145K from elapsed time or clinical inference. The physician note must state that nonunion is present. Structured patient records that capture this level of detail protect the practice during payer audits.

Physical therapy practice compliance requirements set the same bar: documentation has to match what payers expect to see. The checklist below covers the minimum elements needed before S92.145K can be applied.

• Laterality confirmed: clinical notes, imaging reports, or operative notes must specify the left foot or left talus. A bare “talus fracture” forces the unspecified code.
• Displacement status documented: the physician must state that the fracture is nondisplaced. Displacement cannot be assumed from an imaging description without physician interpretation.
• Fracture morphology specified: a dome fracture, not the neck, body, or head of the talus. Each location within the talus has its own S92 subcode.
• Nonunion explicitly documented: the treating physician must record nonunion, failed healing, or absent consolidation. Radiology findings alone are not enough without that interpretation.
• Encounter type is subsequent: the patient must be past the initial active treatment phase. S92.145K cannot be used for the visit where active treatment begins.
• Imaging evidence referenced: cite the X-ray or CT report supporting the nonunion diagnosis in the clinical note to establish medical necessity.

Practices coding across several families often work from a medical coding cheat sheet. Building the same checks into the clinical workflow cuts coding errors and audit risk.

Billing and claim submission

S92.145K is accepted for submission on CMS-1500 professional claims and UB-04 facility claims. It applies across Medicare, Medicaid, and commercial payer claims wherever the diagnostic criteria are met. Orthopedic and physical therapy practices use it to establish medical necessity for continued treatment of talar nonunion.

A valid code is only half of a clean claim. The diagnosis has to match the procedure codes billed at that encounter, and the note has to support both. AAPC Codify lists crosswalk references for pairing S92.145K with related procedure codes.

Commonly paired CPT codes

The diagnosis code establishes medical necessity, and CPT codes describe what was done. For talar dome nonunion, CPT selection depends on what the clinician performs at the encounter. A practice running a return-to-running protocol after talar injury bills differently from a surgical team repairing the nonunion.

CPT pairings must reflect the procedures documented for that specific encounter. Never assign a CPT code for a procedure that was not performed or planned at the visit. Check payer medical necessity policies before submitting surgical nonunion repair codes, because some require prior authorization.

How Pabau keeps nonunion documentation and claims in step

Most practices track a nonunion across three places. The dictated physician note sits in one system, the radiology report in another, and the claim in a third. When a payer questions the fourth follow-up visit billed with S92.145K, someone has to reassemble that trail by hand.

Pabau holds the physician note, the imaging it references, and the assigned diagnosis code on one patient record. Its claims management software then pulls that existing record data into a pre-filled claim and tracks the response. Nothing gets retyped between the chart and the payer.

The result is a shorter trail to assemble when an audit arrives, and fewer denials caused by a diagnosis the note never supported. Your coders spend their time on the ambiguous cases instead of chasing paperwork.

Keep fracture documentation and claims in one place

Pabau keeps physician notes, imaging, and diagnosis codes on a single patient record, then submits and tracks the claim from the same place. Your team spends less time rebuilding an audit trail.

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Conclusion

S92.145K rests entirely on one line in the physician note. Query that note when it hedges, because a query costs minutes and a denied claim costs weeks.

Coders who treat the 7th character as a documentation question rather than a timing question get this code right. The same habit carries across the rest of the S92 family. Book a demo to see how Pabau keeps fracture notes, imaging, and diagnosis codes on one record.

Continue your research

Coding a nonunion in a neighboring tarsal bone? S92.209K walks through the unspecified tarsal fracture code and its documentation requirements.

Working on pediatric foot fractures? S99.101D covers physeal fracture coding and the routine-healing follow-up character.

Ruling out midfoot pain after an ankle injury? Cuboid syndrome test explains how to perform the test and read the result.

Assessing hindfoot alignment before treatment? Coleman block test sets out the technique, the interpretation, and the common variants.

Sending patients home with rehab work? Home exercise program gives you a structured plan to hand over after a fracture.

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