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ICD-10-CM 2027 diagnosis code

W51.XXXAAccidental striking against or bumped into by another person, initial encounter

✓ Billable / specificRequires 7th character

W51.XXXA is a valid, billable ICD-10-CM code for accidental striking against or bumped into by another person, initial encounter. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.Short description: Accidental strike or bumped into by another person, init

Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data

About W51.XXXA

W51.XXXA is the ICD-10-CM diagnosis code for accidental striking against or bumped into by another person, initial encounter. It belongs to category W51 (accidental striking against or bumped into by another person), block W50-W64 (exposure to animate mechanical forces) and chapter 20 (external causes of morbidity). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

The 7th character "A" means initial encounter: use it while the patient is receiving active treatment for the condition.

It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Before ICD-10, this condition was coded in ICD-9-CM as E917.9 (other accident caused by striking against or being struck accidentally by objects or persons).

7th character

Ainitial encounter

Other encounter types for W51:

Notes that apply from higher levels

Instructions written at a parent level also apply to W51.XXXA.

› From W51 Accidental striking against or bumped into by another person
Excludes1
  • assault by striking against or bumping into by another person (Y04.2)
  • fall due to collision with another person (W03)

Broader instructions also apply from W50-W64 Exposure to animate mechanical forces and Chapter 20: External causes of morbidity.

ICD-9-CM equivalent

Converter →
  • E917.9Other accident caused by striking against or being struck accidentally by objects or personsapproximate

From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.

Code history

  1. 2016
  2. 2017
  3. 2018
  4. 2019
  5. 2020
  6. 2021
  7. 2022
  8. 2023
  9. 2024
  10. 2025
  11. 2026
  12. 2027
  • FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
  • No changes since FY2016.

Common questions about W51.XXXA

Is W51.XXXA billable?

Yes. W51.XXXA is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).

What does the "A" at the end of W51.XXXA mean?

It is the 7th character for initial encounter. Per the official guidelines, use it while the patient is receiving active treatment for the condition.

Can W51.XXXA be used as a principal diagnosis?

Yes. The Medicare Code Editor doesn't restrict W51.XXXA as a principal diagnosis.

Is W51.XXXA a CC or MCC?

No. W51.XXXA is neither a CC nor an MCC under MS-DRG v44.0.

What is the ICD-9 code for W51.XXXA?

The CMS General Equivalence Mappings map W51.XXXA to ICD-9-CM E917.9.