ICD-10 code S52.591S: Other fractures of lower right radius, sequela

Key takeaways

S52.591S is a billable ICD-10-CM code for other fractures of the lower end of the right radius, sequela.

The 7th character ‘S’ means the fracture has healed and the patient is being seen for a late effect.

Sequela claims carry two codes: the residual condition first, then S52.591S second.

Parent code S52.591 is not billable on its own, so a valid 7th character is required.

Practice management software like Pabau prompts providers to record the causal link that sequela coding depends on.

S52.591S is a billable ICD-10-CM diagnosis code for other fractures of lower end of right radius, sequela. Coders use it when a patient presents with a late effect of a previously treated fracture at the lower end of the right radius. The fracture itself has already healed.

The code took effect on October 1, 2025 under the FY2026 edition of ICD-10-CM, and stays valid through September 30, 2026. Per the CMS ICD-10 codes page, it is classified as billable and specific. That means it carries enough diagnostic detail for reimbursement without a more granular sub-code.

What does S52.591S mean? Breaking down each segment

Read the code in sequence and each character tells you something. The structure follows standard ICD-10-CM fracture coding conventions.

The “other” classification under S52.59x covers lower-end radius fractures that do not fit a named type. Named fractures at this site have their own codes: Colles’ fracture is S52.53x, Smith’s fracture is S52.54x, and Barton’s fracture is S52.56x. When the injury meets none of those clinical criteria, S52.591S is the right sequela code for the right side.

What the 7th character ‘S’ means for sequela encounters

The 7th character in an ICD-10-CM fracture code defines the type of encounter. In S52.591S, the “S” designates a sequela encounter. That carries clinical and documentation requirements distinct from initial or subsequent encounters.

The CDC ICD-10-CM web tool defines a sequela as a condition that arises as a direct late effect of a prior injury. The original injury has to have healed first.

In fracture coding, that means the patient’s current complaint traces back to the old fracture. Stiffness, chronic pain, malunion, and functional loss all qualify, provided the fracture is not active or re-injured.

Sequela vs. subsequent encounter: The key distinction

Coders confuse sequela encounters with subsequent encounters more often than any other 7th character pair. The distinction is clinically and financially significant.

• Subsequent encounter (7th character D, G, K, M, N, P, Q, R): the original fracture is still healing. The patient is receiving ongoing treatment for the fracture itself.
• Sequela encounter (7th character S): the original fracture has healed. The patient now has a new condition caused by that healed fracture, and the code applies to the late effect.

Applying the wrong 7th character is a common reason fracture claims get denied. Using “S” while the fracture is still healing triggers a claim edit, and so does “D” once a late effect is confirmed.

The same judgment applies to sequela codes elsewhere in the body, such as S81.009S. In physical therapy practices, post-fracture rehab visits raise the question almost daily.

How to sequence S52.591S on a claim

S52.591S goes second on the claim, never first. The ICD-10-CM Official Guidelines ask you to code the residual condition first, then add the sequela code that explains where it came from. One code on its own tells the payer half the story.

Take a patient with stiffness in the right wrist after a healed distal radius fracture. The stiffness is coded first, using a musculoskeletal code such as M25.631. S52.591S follows it, identifying the injury that produced the stiffness.

There is one exception worth knowing. Some sequela codes already name the residual condition in the code title, so no second code is needed. S52.591S is not one of those, which is why it always travels with a partner code.

All 7th character variants for S52.591

S52.591 needs a valid 7th character before it can be billed. The table below covers every valid character and what it means clinically.

The letter “I” is never used as a 7th character in ICD-10-CM fracture coding, because it reads too easily as the numeral 1.

The AAPC Codify ICD-10-CM lookup is a searchable reference for checking valid character combinations across the S52 category. G, K, and P are the ones worth building into your coding workflow, since complicated healing is where errors cluster.

Clinical scenarios for using S52.591S

Use S52.591S when a condition left behind by an old fracture is what drives the visit. The fracture has to be at the lower end of the right radius. The fracture itself is no longer active.

Common presentations that warrant the code include:

• Post-fracture wrist stiffness: reduced range of motion in the right wrist, attributed to scar tissue or joint changes after the fracture healed
• Chronic pain at the distal radius: ongoing pain at the lower end of the right radius with no sign of re-fracture or active nonunion
• Functional deficit after a healed fracture: loss of grip strength or fine motor control that traces directly back to the original injury
• Post-fracture arthritis: wrist joint degeneration that developed as a long-term consequence of the fracture

Clinicians working in occupational therapy meet these presentations weekly. The provider’s note has to establish the causal link between today’s condition and the prior fracture.

Without that language, payers reject the sequela coding and expect a different encounter type. Sequela codes in other categories carry the same requirement, including S12.14XS.

Documentation requirements for S52.591S

Accurate coding starts with the record. Before a coder assigns S52.591S, the provider’s documentation has to support every element of it.

• Confirmed prior fracture: the record shows that a fracture of the lower end of the right radius occurred and has healed
• Causal relationship language: the note states that the current condition is a consequence of that fracture, not a new injury
• Laterality confirmation: right-side specificity is documented, since left-side sequelae use S52.592S
• Current condition description: the late effect being treated is described, because the sequela code alone does not capture it
• No active fracture signs: the note confirms healing, since imaging that suggests an active fracture changes the 7th character

Structured templates make this easier to enforce. Practices using clinical documentation tools can build note templates that prompt providers for each element at the point of care. Pairing those notes with digital intake forms that capture injury history catches sequela errors before they reach billing.

Those records also have to meet HIPAA compliance standards, since an injury history is protected health information like any other part of the chart.

Related ICD-10-CM codes for distal radius fractures

S52.591S sits inside a wider family of codes for fractures of the lower end of the radius. Reading the neighboring codes helps confirm you have picked the most specific option available.

Procedure coding runs on a separate track. A wrist operation during the same episode of care is billed under its own code, such as CPT 25110.

S52.591S code history and FY2026 update status

ICD-10-CM codes are updated every year on October 1, under guidance from the National Center for Health Statistics and CMS. The CDC web tool linked above is the authoritative place to confirm a code’s status for any fiscal year.

S52.591S has stayed stable across recent fiscal years, with no description changes, deletion notices, or validity flags. Annual updates can still change several categories at once, so verify the code before each October transition.

How Pabau supports accurate ICD-10 coding workflows

Misapplied 7th characters account for a large share of preventable fracture claim denials. The trouble usually starts at the point of care. A provider writes up the findings, but never states the causal link the sequela code depends on.

Practice management software like Pabau connects clinical documentation to billing, so coding works from structured notes rather than retrospective free-text review.

Our claims management tools let you configure encounter templates that prompt for injury history, laterality, and causal language during the visit. Your coding team then has the specificity S52.591S needs.

Pabau’s compliance management features keep a timestamped record of every clinical note and coding decision. That record is what you hand over when a payer asks you to support a sequela claim.

Reduce ICD-10 coding errors across your practice

Pabau connects clinical documentation to billing, so your team captures the right encounter data, assigns accurate ICD-10 codes, and submits cleaner claims. See how it works for your specialty.

Book a demo

Conclusion

The whole S52.591S decision rests on one question. Has the fracture healed? If it has, and today’s complaint traces back to it, the sequela character is correct. If healing is still under way, a subsequent-encounter character belongs there instead.

Then get the order right. The residual condition leads, S52.591S follows, and the note carries the causal language that ties the two together. Practices that build all three into their templates catch the error while the patient is still in the room.

Sequela coding rewards the practice that writes the link down at the time of the visit. Book a demo to see how Pabau turns structured clinical notes into cleaner ICD-10 claims.

Continue your research

Need a structured approach to documentation compliance? A complete HIPAA compliance checklist for primary care covers the record-keeping standards that accurate diagnosis coding rests on.

Billing rehab visits alongside a fracture sequela? CPT code 97161 walks through the low complexity physical therapy evaluation that often opens a post-fracture episode.

Coding a sequela outside the forearm? ICD-10 code S78.922S applies the same 7th character logic to a very different injury site.

Billing for health and wellness coaching too? Coaching CPT codes sets out the 2026 billing rules for coaching services delivered alongside clinical care.

Frequently asked questions