S55
Injury of blood vessels at forearm level
S55 is a non-billable ICD-10-CM code category for injury of blood vessels at forearm level. Report a more specific code from it instead. It is part of the FY2027 code set, effective October 1, 2026. The more specific codes under it are S55.0 Injury of ulnar artery at forearm level, S55.1 Injury of radial artery at forearm level, S55.2 Injury of vein at forearm level, S55.8 Injury of other blood vessels at forearm level and 1 more. Its coding notes include a Use additional code instruction, a Code also instruction and 8 Excludes2 entries.
7th characters
Every code below needs one of these.
The appropriate 7th character is to be added to each code from category S55
- Ainitial encounter
- Dsubsequent encounter
- Ssequela
Guidelines tips
From the FY2027 Official Guidelines. ICD10Ref adds no rules of its own.
The 7th character depends on whether the patient is in active treatment, not on who sees the patient. An aftercare Z code is not used for injury aftercare.
Each injury gets its own code unless a combination code exists, with the most serious injury first. Superficial injuries at the same site as a more severe injury are not coded. Injuries during medical care are coded as complications.
Use additional code
Add the listed code as a secondary code, if known.
Also from chapter/block level (1 note)
- code to identify any retained foreign body, if applicable (Z18.-)
Code also
Two codes may be needed to describe the condition. This note gives no sequencing order.
- any associated open wound (S51.-)
Excludes2
Not included here. Both codes may be reported if the patient has both conditions.
Also from chapter/block level (6 notes)
- birth trauma (P10-P15)
- obstetric trauma (O70-O71)
Notes
Also from chapter/block level (2 notes)
- Use secondary code(s) from Chapter 20, External causes of morbidity, to indicate cause of injury. Codes within the T section that include the external cause do not require an additional external cause code
- The chapter uses the S-section for coding different types of injuries related to single body regions and the T-section to cover injuries to unspecified body regions as well as poisoning and certain other consequences of external causes.