Chapter 20 External Causes of Morbidity includes codes from V00 to Y99. They were greatly expanded in ICD-10-CM. They are intended to provide data for injury research and evaluation of injury prevention strategies. These codes capture how the injury or health condition happened (cause), the intent (unintentional or accidental; or intentional, such as suicide or assault), the place where the event occurred, the activity of the patient at the time of the event, and the person’s status (e.g. civilian, military). Therefore they don’t actually describe a condition, rather they just provide additional data.

The chapter includes codes that begin with the letters V, W, X, and Y and they are broken up into 29 blocks, such as V90-V94 Water transport accidents, W00-W19 Slipping, tripping, stumbling and falls, and W50-W64 Exposure to animate mechanical forces. There is no national requirement for mandatory external cause code reporting, but voluntary reporting is encouraged.

It may be helpful to review the chapter specific guidelines for external cause codes found in section 1.C.20. Several guidelines and definitions also appear at the beginning of Chapter 20 within the Tabular List. A review of these rules is essential for a complete understanding of external cause code reporting. If you have not ordered yours yet, you can purchase the 2016 ICD-10-CM Coding for Chiropractic book here.

Chiropractors may elect to add these codes to personal injury cases because they may allow third parties to obtain information from the claim form, without needing to review the medical records. Auto injury claims might use the codes that begin with the letter “V”, which are all transport accidents.

There are 12 groups of transport accident types, and first two characters identify the vehicle or type of transportation. For example, V4- is used for car occupants.

The next character identifies the object that was struck. The following code might be used on the claim for a passenger of a car who was injured when the car struck a pick-up truck in traffic.

V43.63xA Car passenger injured in collision with pick-up truck in traffic accident, initial encounter

If these codes are used, then all of this information must be documented in the record because the claim form is only a reflection of the documentation.

Note that these codes should never be sequenced first since they only provide additional data. The primary reason for the encounter should always be listed first. For more information common external cause codes that might be useful to chiropractors, see the Common Codes section of the  2016 ICD-10-CM Coding for Chiropractic.