S90.521D — Blister (nonthermal), right ankle, subsequent encounter
Is S90.521D billable?
Yes — S90.521D is billable for FY2027. S90.521D is a valid, billable ICD-10-CM code at the highest level of specificity in its branch. S90.521D may be submitted for encounters from October 1, 2026 through September 30, 2027.
S90.521D at a glance
| Code | S90.521D |
|---|---|
| Description | Blister (nonthermal), right ankle, subsequent encounter |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
| 7th character "D" | subsequent encounter |
What does the 7th character "D" mean in S90.521D?
In S90.521D, the 7th character D means subsequent encounter. The 7th character is required for S90.521D to be a valid, complete code.
Same condition, different episode of care — switch the 7th character:
Which MS-DRGs does S90.521D group to?
S90.521D sits in MDC 23 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.
- 949Aftercare with CC/MCCmedical
- 950Aftercare without CC/MCCmedical
How is S90.521D listed in the Alphabetic Index?
The Alphabetic Index lists these routes under S90.52, the nearest indexed parent of S90.521D. Use them to find the family, then select the specific code.
- Blister › ankle (nonthermal)
Use additional code — inherited from Chapter 19
Report an additional code alongside S90.521D to fully describe the condition. S90.521D 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 S90.521D, but a patient may have both at the same time. When documentation supports it, S90.521D and the excluded code may both be reported.
Excludes2 — not included here — inherited from S90-S99
The conditions below are not part of S90.521D, but a patient may have both at the same time. When documentation supports it, S90.521D and the excluded code may both be reported.
How long has S90.521D existed?
S90.521D 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.