Skip to main content

S66.921A vs S66.921D

S66.921A (Laceration of unspecified muscle, fascia and tendon at wrist and hand level, right hand, initial encounter) compared with S66.921D (Laceration of unspecified muscle, fascia and tendon at wrist and hand level, right hand, subsequent encounter), from the official CMS tabular data. S66.921A and S66.921D code the same injury at a different phase of treatment. MedCoder-derived

Relationship

Review

Encounter relationship

S66.921A
Initial encounter
Laceration of unspecified muscle, fascia and tendon at wrist and hand level, right hand, initial encounter
S66.921D
Subsequent encounter
Laceration of unspecified muscle, fascia and tendon at wrist and hand level, right hand, subsequent encounter

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

Can these codes be reported together?

Same injury, other encounter phase. S66.921A and S66.921D 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.

Side by side

S66.921ALaceration of unspecified muscle, fascia and tendon at wrist and hand level, right hand, initial encounterS66.921DLaceration of unspecified muscle, fascia and tendon at wrist and hand level, right hand, subsequent encounter
Billing statusBillableBillable
ClassificationS00-T88 — Injury, poisoning and certain other consequences of external causesS00-T88 — Injury, poisoning and certain other consequences of external causes
DefinitionLaceration of unspecified muscle, fascia and tendon at wrist and hand level, right hand, initial encounter is a billable ICD-10-CM diagnosis code (S66.921A).Laceration of unspecified muscle, fascia and tendon at wrist and hand level, right hand, subsequent encounter is a billable ICD-10-CM diagnosis code (S66.921D).
7th characterThe appropriate 7th character is to be added to each code from category S66The appropriate 7th character is to be added to each code from category S66

Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources