S99.811A: Other specified injuries of right ankle, initial encounter
S99.811A, other specified injuries of right ankle, initial encounter, is listed as a covered diagnosis in 4 Medicare billing and coding articles that apply to 2 HCPCS Level II codes, including G0127 (Trimming of dystrophic nails, any number), G0255 (Current perception threshold/sensory nerve conduction…). The articles come from 3 Medicare contractors. A listed diagnosis supports medical necessity only; coverage still depends on the LCD's criteria and on documentation in the medical record.
HCPCS Level II codes with S99.811A as a covered diagnosis
| Code | Description | Medicare coverage | DMEPOS fee 2026 (state range) | Articles listing it |
|---|---|---|---|---|
| G0127 | Trimming of dystrophic nails, any number | Special coverage instructions apply | — | 3 |
| G0255 | Current perception threshold/sensory nerve conduction test, (snct) per limb, any nerve | Non-covered by Medicare | Not covered | 1 |
Medicare policy articles listing S99.811A
- A52996: Billing and Coding: Routine Foot Care (Novitas Solutions, Inc. (MAC - Part A, MAC - Part B); 1 Level II codes). LCD with the same title: L33941, L35138, L37643
- A56232: Billing and Coding: Foot Care (WPS Insurance Corporation (MAC - Part A, MAC - Part B); 1 Level II codes)
- A56680: Billing and Coding: Routine Foot Care (Palmetto GBA (MAC - Part A, MAC - Part B); 1 Level II codes). LCD with the same title: L33941, L35138, L37643
- A56619: Billing and Coding: Nerve Conduction Studies and Electromyography (Palmetto GBA (MAC - Part A, MAC - Part B); 1 Level II codes). LCD with the same title: L34594, L34859, L35048, L35081
A diagnosis listed as covered in a billing and coding article supports medical necessity for the article's codes; it does not guarantee payment. Coverage depends on the LCD's criteria, the contractor's jurisdiction and documentation in the medical record.
Other S99 diagnoses (Other and unspecified injuries of ankle and foot)
- S99.812A — Other specified injuries of left ankle, initial encounter
- S99.821A — Other specified injuries of right foot, initial encounter
- S99.822A — Other specified injuries of left foot, initial encounter
- S99.911A — Unspecified injury of right ankle, initial encounter
- S99.912A — Unspecified injury of left ankle, initial encounter
- S99.921A — Unspecified injury of right foot, initial encounter
- S99.922A — Unspecified injury of left foot, initial encounter
Frequently asked questions
Does Medicare cover S99.811A (Other specified injuries of right ankle, initial encounter)?
Medicare covers items and services, not diagnoses. 4 Medicare billing and coding articles list S99.811A as a covered diagnosis for 2 HCPCS Level II codes: the diagnosis can support medical necessity for those codes, but payment still depends on the LCD's coverage criteria and the medical record.
Which HCPCS codes can be billed with ICD-10 S99.811A?
The Level II codes from the policies most specific to this diagnosis are G0127 (Trimming of dystrophic nails, any number, 3 articles); G0255 (Current perception threshold/sensory nerve conduction…, 1 article). Code choice depends on the item supplied; check each code's descriptor.
Which Medicare policy articles list S99.811A?
A52996 (Billing and Coding: Routine Foot Care); A56232 (Billing and Coding: Foot Care); A56680 (Billing and Coding: Routine Foot Care), and 1 more article.
What is ICD-10-CM code S99.811A?
S99.811A is the ICD-10-CM code for other specified injuries of right ankle, initial encounter, in category S99 (Other and unspecified injuries of ankle and foot), chapter 19: Injury, poisoning and other consequences of external causes.
Next steps
- Run a reimbursement report for a device billed under G0127
- Watch G0127 for fee, coverage and descriptor changes
- Build a full Medicare revenue model for G0127
Sources: CMS Medicare Coverage Database billing and coding articles (covered ICD-10 code lists and HCPCS links); ICD-10-CM FY2026; CMS HCPCS Level II release October 2026; CMS DMEPOS fee schedule 2026 (non-rural state fees). Not billing or legal advice.
Chapter 19: Injury, poisoning and other consequences of external causes · All diagnoses · HCPCS lookup