S81.859A — Open bite, unspecified lower leg, initial encounter
Is S81.859A billable?
Yes, but S81.859A is an unspecified code. S81.859A is a valid, billable ICD-10-CM code for encounters from October 1, 2026 through September 30, 2027. However, S81.859A is an unspecified or catch-all code. Payers apply additional scrutiny to unspecified codes and many deny them when the medical record supports a more specific option, so check the documentation before selecting S81.859A — the more specific alternatives are listed below.
S81.859A at a glance
| Code | S81.859A |
|---|---|
| Description | Open bite, unspecified lower leg, initial encounter |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
| 7th character "A" | initial encounter |
What does the 7th character "A" mean in S81.859A?
In S81.859A, the 7th character A means initial encounter. The 7th character is required for S81.859A to be a valid, complete code.
Same condition, different episode of care — switch the 7th character:
Which MS-DRGs does S81.859A group to?
S81.859A sits in MDC 09 and helps define the logic of 2 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.
- 604Trauma to the Skin, Subcutaneous Tissue and Breast with MCCmedical
- 605Trauma to the Skin, Subcutaneous Tissue and Breast without MCCmedical
How is S81.859A listed in the Alphabetic Index?
The Alphabetic Index lists these routes under S81.85, the nearest indexed parent of S81.859A. Use them to find the family, then select the specific code.
- Bite › leg (s) (animal) (human)
Excludes1 — never code together — inherited from S81
The conditions below can never be reported together with S81.859A on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
Excludes1 — never code together — inherited from S81.85
The conditions below can never be reported together with S81.859A on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
Use additional code — inherited from Chapter 19
Report an additional code alongside S81.859A to fully describe the condition. S81.859A is sequenced first.
- code to identify any retained foreign body, if applicable (Z18.-)
Excludes2 — not included here — inherited from Chapter 19
The conditions below are not part of S81.859A, but a patient may have both at the same time. When documentation supports it, S81.859A and the excluded code may both be reported.
Excludes2 — not included here — inherited from S80-S89
The conditions below are not part of S81.859A, but a patient may have both at the same time. When documentation supports it, S81.859A and the excluded code may both be reported.
Excludes2 — not included here — inherited from S81
The conditions below are not part of S81.859A, but a patient may have both at the same time. When documentation supports it, S81.859A and the excluded code may both be reported.
- open wound of ankle and foot (S91.-)
Code also — inherited from S81
Two codes may be needed to describe the condition fully. Whether S81.859A is sequenced first depends on the reason for the encounter.
- any associated wound infection
How long has S81.859A existed?
S81.859A has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.