ICD-10 Code S90.416D: Abrasion, unspecified lesser toes

Key takeaways

ICD-10 Code S90.416D describes an abrasion of the unspecified lesser toe(s) coded at a subsequent encounter, under ICD-10-CM FY2026.

The 7th character D confirms the patient is in the healing phase – active treatment has ended and routine follow-up care is underway.

Wrong 7th character assignment (using A instead of D) is one of the most common reasons superficial toe injury claims are denied.

Practice management software like Pabau links diagnosis codes such as S90.416D directly to visit records, keeping the documentation trail complete.

ICD-10 Code S90.416D is a billable code for an abrasion of the unspecified lesser toe(s) at a subsequent encounter. It applies when the patient returns for follow-up wound care after active treatment has ended. Getting the 7th character right matters every time the patient comes back for a wound check or dressing change. This reference covers the full code definition, the 7th character logic, the classification hierarchy, related codes, and the billing documentation that keeps these claims clean.

ICD-10 Code S90.416D: definition and billable status

ICD-10 Code S90.416D is a billable, specific ICD-10-CM diagnosis code. It describes an abrasion of the unspecified lesser toe(s) at a subsequent encounter. The patient has already received active treatment for the injury and is now attending a follow-up visit during the healing phase. The code is valid for HIPAA-covered transactions under the FY2026 edition of ICD-10-CM, which became effective October 1, 2025. For solid healthcare billing compliance, every field on the claim needs to match the clinical documentation.

Understanding the 7th character: A, D, and S for S90.416

The parent code S90.416 (abrasion, unspecified lesser toe(s)) is not itself billable. To submit a claim, coders must append a 7th character that specifies the type of encounter. This structure applies across injury codes in the S00-T88 range.

What is a subsequent encounter?

Per the ICD-10-CM Official Guidelines (Section I.C), a subsequent encounter applies once active treatment for the injury has ended. The patient is then receiving routine care during healing. The provider no longer needs to assess or manage the original wound in an active clinical sense. They are monitoring recovery, changing dressings, or confirming the abrasion is resolving as expected.

The key distinction from an initial encounter (A): that first visit could span multiple appointments if active treatment continues. Once healing begins and care becomes routine, the encounter type shifts to D. A single patient may generate both S90.416A and S90.416D claims across the same episode of care. The two codes just never apply on the same date of service for the same injury.

What is a sequela (S)?

Sequela codes require a second diagnosis code identifying the specific late effect being treated. If a patient returns months later for scar tissue management on the same toe, S90.416S pairs with a code describing the scar condition. Sequela coding is less common for superficial abrasions, but it is accurate when the complication is clearly traceable to the original injury.

Anatomy: what are the lesser toes?

The lesser toes in ICD-10-CM terminology are toes 2 through 5. The great toe (digit 1) is coded separately throughout the S90 range. When a clinician documents an abrasion on the second, third, fourth, or fifth toe without specifying which one, the “unspecified lesser toe(s)” descriptor applies.

• Toe 1 (great toe): Coded under S90.41x (S90.411-S90.413), not under the S90.414-416 lesser-toe range
• Toes 2-5 (lesser toes): Covered under S90.414 (right), S90.415 (left), or S90.416 (unspecified laterality)
• Unspecified: Use when documentation does not specify left vs. right, or when laterality is not clinically relevant to the encounter

The “unspecified” modifier on S90.416 refers to laterality, not the severity of the abrasion. If the provider documents “left lesser toe abrasion” clearly, code S90.415 (with the appropriate 7th character) is more precise. Use S90.416D only when documentation is genuinely silent on side.

This kind of superficial toe injury is common in athletic settings, from turf toe to cleat abrasions and running injuries. Practices using sports medicine software can flag the encounter-type shift from A to D as an athlete progresses through recovery.

Code hierarchy and classification for S90.416D

Understanding where S90.416D sits in the classification tree helps coders verify they are working in the right section. The same chapter-to-digit structure applies to codes like S21.112A, and it is straightforward to trace once you know the pattern.

Synonyms and approximate terms

Medical coders working from chart notes may see several different clinical descriptions that map to this code. Coding reference tools often include an approximate synonyms section for exactly this reason. The following terms all index to S90.416D when documentation supports a subsequent encounter context.

• Abrasion of toe, subsequent encounter
• Abrasion of lesser toe, subsequent encounter
• Abrasion of toe (not great toe), subsequent encounter
• Superficial wound of lesser toe, subsequent encounter
• Skin abrasion of toe, follow-up visit
• Minor toe wound, subsequent encounter

These are not separate codes. They are natural-language entries in the ICD-10-CM Alphabetic Index that point coders toward S90.416 as the appropriate code family. The 7th character D is applied based on the encounter type documented in the chart, not the synonym used.

Related ICD-10-CM codes

S90.416D sits within a closely related family of codes. Coders need to distinguish between encounter types (A/D/S) and laterality (left, right, unspecified). The table below covers the primary sibling and parent codes that come up in toe abrasion documentation. Coders can verify the full code tree using the CDC/NCHS ICD-10-CM web tool.

Excludes notes and coding restrictions

S90.416D carries no Excludes1 note of its own. It inherits several Excludes2 notes from its chapter (S00-T88) and block (S90-S99), from the ICD-10-CM tabular list.

• Excludes2 – Burns and corrosions (T20-T32): A burn or chemical corrosion of the toe is coded from the T20-T32 range, not as an abrasion
• Excludes2 – Fracture of ankle and malleolus (S82.-): A fractured ankle or malleolus uses its own S82 code, separate from a toe abrasion
• Excludes2 – Frostbite (T33-T34): Cold-injury damage to the toe is coded as frostbite, not as a mechanical abrasion
• Excludes2 – Insect bite or sting, venomous (T63.4): A venomous insect bite or sting to the toe is coded from T63.4, not S90.416D

Because these are Excludes2 notes rather than Excludes1, S90.416D can be reported alongside a burn, fracture, frostbite, or venomous-sting code. Confirm the chart documents both conditions separately before submitting both codes.

Common CPT codes paired with S90.416D

Billing a subsequent encounter for a lesser toe abrasion typically involves one of three service categories. These are an evaluation and management (E/M) visit, a wound care procedure, or a dressing change. The CPT codes below are the most frequently paired with S90.416D in follow-up wound care billing, based on standard wound care practice. Verify payer-specific requirements using the AAPC Codify ICD-10-CM lookup and current AMA CPT guidelines. Clinics managing multiple wound care follow-ups benefit from physical therapy EMR or dedicated wound care modules that link diagnosis and procedure codes automatically.

Add-on code 11001 applies once debridement of the abrasion site extends beyond the first 20 sq cm covered by 97597.

How Pabau documents subsequent-encounter wound care visits

Practices tracking toe abrasions through multiple follow-up visits often juggle separate systems for scheduling, chart notes, and billing codes. A coder billing S90.416D weeks later has to reconstruct whether the chart actually documented a subsequent encounter.

Pabau keeps the diagnosis code, the visit note, and the CPT pairing in one record from the point of care. A note like “wound healing well, dressing changed” sits alongside the S90.416D code and the CPT code billed that day. The 7th character choice stays traceable to the clinical language that supports it.

The result is a wound care record that holds up if a payer queries the shift from an initial to a subsequent encounter. No separate reconciliation step is needed before the claim goes out.

Keep wound care documentation audit-ready with Pabau

Pabau links ICD-10 diagnosis codes to visit records automatically, so the documentation behind each subsequent-encounter claim is captured at the point of care.

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Billing and documentation tips for subsequent encounter claims

Documentation checklist before submission

Claims for S90.416D fail for predictable reasons – and most of them trace back to documentation, not the code itself. The chart must support the subsequent encounter designation before the code is ever used. Coders working on HIPAA-compliant billing workflows should verify four elements before submission.

• Active treatment status: The record must show that initial active treatment has concluded. If the provider is still assessing wound depth, ordering tests, or making treatment decisions, the encounter may still be initial (A), not subsequent (D).
• Healing phase documentation: Notes should explicitly describe the wound’s healing status. Phrases like “abrasion healing well,” “dressing changed, no signs of infection,” or “wound inspected, patient doing well” support the D character assignment.
• Laterality default: If either left or right is documented, use the laterality-specific code (S90.414D or S90.415D) rather than S90.416D. Reserve the unspecified code for genuinely undocumented cases.
• Encounter type consistency: The date of service, the CPT code, and the ICD-10-CM code must all align. A 99213 (E/M with decision-making) billed with S90.416D requires chart documentation that justifies the complexity level – not just the diagnosis.
• Excludes1 check: Confirm the wound has not evolved into an open injury (S91 range). Re-examine wound descriptors every visit; a previously superficial abrasion can progress.

A documented range of motion assessment at the subsequent visit can justify a higher E/M level, such as 99213 rather than 99212.

Using Pabau to track subsequent-encounter documentation

Practices managing high volumes of wound care follow-ups can use Pabau to attach diagnosis codes to the visit record at the point of care. This flags encounter-type mismatches before submission. Good patient care documentation at each visit also builds an auditable record of the healing timeline. That record is useful if a payer queries the transition from A to D.

For practices using digital intake forms, capturing wound status at each follow-up visit as a structured field works better than free text. It makes the billing team’s job faster and reduces the chance of a coder missing the encounter-type shift. Using HIPAA transaction requirements as a framework, every field submitted on a claim should have a corresponding entry in the patient record.

Related ICD-10 codes

• ICD-10 code S83.241 — Other Tear of Medial Meniscus, Right Knee
• ICD-10 Code S90.519A — Ankle Abrasion
• ICD-10 code S90.812D — Left foot abrasion
• ICD-10 Code S92.042G — Calcaneus Fracture

Conclusion

S90.416D is a narrow code, but it fails often when the chart does not clearly separate the initial visit from the follow-up. Confirm the encounter type, the laterality, and the CPT level before the claim goes out, not after a denial comes back.

Pabau links ICD-10-CM diagnosis codes directly to visit records and CPT pairings. The documentation that supports S90.416D is captured at the point of care instead of pieced together later. To see how it works in a wound care or outpatient setting, book a demo.

Continue your research

Coding a sequela for an old injury? S31.607S covers an abdominal wall open wound sequela, with the same late-effect documentation logic.

Need a sequela code for a vascular injury? S15.029S explains billing for a major carotid artery laceration sequela.

Billing a surgical wound preparation? 15004 covers surgical preparation for high-complexity wound sites.

Coding a skin graft on the foot? 15120 covers split-thickness autografts for the face, hands, and feet.

Need a burn injury code instead? T31.11 covers burns involving 10-19% TBSA with third-degree involvement.

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