S55.999A Other specified injury of unspecified blood vessel at forearm level, unspecified arm, initial encounter

Billable ICD-10-CM code, FY2026.

Built from S55.999 with 7th character A (initial encounter).

Applies from S55 Injury of blood vessels at forearm level

Excludes2 (not included here)

• injury of blood vessels at wrist and hand level (S65.-)
• injury of brachial vessels (S45.1-S45.2)

Code also

• any associated open wound (S51.-)

7th character note

• The appropriate 7th character is to be added to each code from category S55

7th character required

• A — initial encounter
• D — subsequent encounter
• S — sequela

Medicare Code Edits (MCE v43.1 (April 2026))

• Unspecified code (laterality): Unspecified codes for which a more specific code identifying laterality (right, left, bilateral) exists within the same code family.

Nearby codes

• S55.992 Other specified injury of unspecified blood vessel at forearm level, left arm
• S55.992A Other specified injury of unspecified blood vessel at forearm level, left arm, initial encounter
• S55.992D Other specified injury of unspecified blood vessel at forearm level, left arm, subsequent encounter
• S55.992S Other specified injury of unspecified blood vessel at forearm level, left arm, sequela
• S55.999 Other specified injury of unspecified blood vessel at forearm level, unspecified arm
• S55.999A Other specified injury of unspecified blood vessel at forearm level, unspecified arm, initial encounter (this code)
• S55.999D Other specified injury of unspecified blood vessel at forearm level, unspecified arm, subsequent encounter
• S55.999S Other specified injury of unspecified blood vessel at forearm level, unspecified arm, sequela