S93.409A (Sprain of unspecified ligament of unspecified ankle, initial encounter) compared with S93.409D (Sprain of unspecified ligament of unspecified ankle, subsequent encounter), from the official CMS tabular data. S93.409A and S93.409D code the same injury at a different phase of treatment.
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. S93.409A and S93.409D 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.
| S93.409ASprain of unspecified ligament of unspecified ankle, initial encounter | S93.409DSprain of unspecified ligament of unspecified ankle, subsequent encounter | |
|---|---|---|
| Billing status | Billable | Billable |
| Classification | S00-T88 — Injury, Poisoning and Certain Other Consequences of External Causes (S00-T88) | S00-T88 — Injury, Poisoning and Certain Other Consequences of External Causes (S00-T88) |
| Definition | Sprain of unspecified ligament of unspecified ankle, initial encounter is a billable ICD-10-CM diagnosis code (S93.409A). | Sprain of unspecified ligament of unspecified ankle, subsequent encounter is a billable ICD-10-CM diagnosis code (S93.409D). |
| 7th character | The appropriate 7th character is to be added to each code from category S93 | The appropriate 7th character is to be added to each code from category S93 |
| Includes | avulsion of joint or ligament of ankle, foot and toe laceration of cartilage, joint or ligament of ankle, foot and toe sprain of cartilage, joint or ligament of ankle, foot and toe traumatic hemarthrosis of joint or ligament of ankle, foot and toe | avulsion of joint or ligament of ankle, foot and toe laceration of cartilage, joint or ligament of ankle, foot and toe sprain of cartilage, joint or ligament of ankle, foot and toe traumatic hemarthrosis of joint or ligament of ankle, foot and toe |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources