S81.831A (Puncture wound without foreign body, right lower leg, initial encounter) compared with S81.831S (Puncture wound without foreign body, right lower leg, sequela), from the official CMS tabular data. S81.831A and S81.831S code the same injury at a different phase of treatment. MedCoder-derived
Same underlying diagnosis, different encounter phase.
The 7th character records the phase of care for the encounter being coded, so a single encounter takes one of these characters, not several. Review whether both phases belong on the same episode of care.
Source: ICD-10-CM Official Guidelines, Section I.C.19.a
Same injury, other encounter phase. S81.831A and S81.831S code the same injury at a different phase of treatment, set by the 7th character.
The 7th character records the type of care given at the encounter being coded (ICD-10-CM Official Guidelines, Section I.C.19.a), so one encounter takes one of these, not both.
| S81.831APuncture wound without foreign body, right lower leg, initial encounter | S81.831SPuncture wound without foreign body, right lower leg, sequela | |
|---|---|---|
| Billing status | Billable | Billable |
| Classification | S00-T88 — Injury, poisoning and certain other consequences of external causes | S00-T88 — Injury, poisoning and certain other consequences of external causes |
| Definition | Puncture wound without foreign body, right lower leg, initial encounter is a billable ICD-10-CM diagnosis code (S81.831A). | Puncture wound without foreign body, right lower leg, sequela is a billable ICD-10-CM diagnosis code (S81.831S). |
| 7th character | The appropriate 7th character is to be added to each code from category S81 | The appropriate 7th character is to be added to each code from category S81 |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources