W51.XXXA

Accidental striking against or bumped into by another person, initial encounter

FY2027Chapter 20: External causes of morbidity/W50–W64 Exposure to animate mechanical forces

BillableComplete code, valid to report

W51.XXXA (also written W51XXXA) is a billable ICD-10-CM diagnosis code for accidental striking against or bumped into by another person, initial encounter. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 3 codes in category W51 (Accidental striking against or bumped into by another person). Its 7th character, A, means initial encounter. Its coding notes include 3 Excludes1 entries.

7th character

Category W51 requires a 7th character. W51 has only 3 characters, so a placeholder X fills the empty positions.

Assembled code W51.XXXA Open code

Guidelines tip

From the FY2027 Official Guidelines. ICD10Ref adds no rules of its own.

An external cause code is never a principal or first-listed diagnosis. Its 7th character is assigned for each encounter and should match the injury or condition code.

Guidelines I.C.20.a.2; I.C.20.a.6External cause codesRead the official text

Excludes1

Not coded here. The listed conditions generally should not be reported together.

Inherited from W51 Accidental striking against or bumped into by another person
  • assault by striking against or bumping into by another person (Y04.2)
  • fall due to collision with another person (W03)
Also from chapter/block level (1 note)
Inherited from W50–W64 Exposure to animate mechanical forces
  • Toxic effect of contact with venomous animals and plants (T63.-)

Notes

Also from chapter/block level (1 note)
Inherited from Chapter 20 External causes of morbidity
  • This chapter permits the classification of environmental events and circumstances as the cause of injury, and other adverse effects. Where a code from this section is applicable, it is intended that it shall be used secondary to a code from another chapter of the Classification indicating the nature of the condition. Most often, the condition will be classifiable to Chapter 19, Injury, poisoning and certain other consequences of external causes (S00-T88). Other conditions that may be stated to be due to external causes are classified in Chapters I to XVIII. For these conditions, codes from Chapter 20 should be used to provide additional information as to the cause of the condition.