ICD-10 Coding for Traumatic Skin Tear on Leg
For a skin tear on the leg resulting from trauma (hitting the leg against something), the appropriate ICD-10-CM code is S81.801A (Unspecified open wound, right lower leg, initial encounter) or S81.802A (left lower leg), with an external cause code from the W series to specify the mechanism of injury.
Primary Diagnosis Code Structure
The ICD-10-CM system requires specific documentation of several key elements for traumatic leg injuries 1:
- Anatomical location: Lower leg (between knee and ankle)
- Laterality: Right or left side
- Encounter type: Initial encounter (A), subsequent encounter (D), or sequela (S)
- Degree of healing: For wounds, whether acute or healing
Specific Code Selection for Skin Tears
Nature of Injury Code (Primary Diagnosis):
- S81.801A - Unspecified open wound, right lower leg, initial encounter
- S81.802A - Unspecified open wound, left lower leg, initial encounter
- S81.809A - Unspecified open wound, unspecified lower leg, initial encounter (if laterality unknown)
These codes from the S81 series are appropriate for skin tears as they represent open wounds of the lower leg 1.
External Cause Codes (Secondary)
You must also assign an external cause code to document the mechanism and intent 2, 3:
- W22.8XXA - Striking against or struck by other objects, initial encounter (most appropriate for hitting leg against something)
- W50-W64 series - Other accidental threats to breathing or striking injuries
- Y93 series - Activity codes (optional but recommended to specify what activity was being performed)
- Y92 series - Place of occurrence codes (to document where injury occurred)
Documentation Requirements
The ICD-10-CM structure for this injury requires 1:
- Principal diagnosis: The nature-of-injury code (S81.8XXA series)
- Secondary diagnosis: External cause code (W22.8XXA or similar)
- Optional modifiers: Activity and place codes for enhanced specificity
Clinical Context for Coding
While the provided guidelines focus primarily on diabetic foot ulcers and complex wounds 4, a simple traumatic skin tear requires straightforward trauma coding. The key distinction is that this is an acute traumatic injury, not a chronic wound or ulcer 5.
Subsequent Encounters
For follow-up visits, modify the seventh character 1:
- "D" for subsequent encounter during healing phase
- "S" for sequela if long-term complications develop
Important Coding Caveats
- Avoid using unspecified codes when specific information is available - document right versus left leg 1
- The external cause code is mandatory for injury surveillance and should always accompany the nature-of-injury code 2, 3
- If the skin tear becomes infected or develops complications, additional codes for infection (L08.9 for local skin infection) may be required 4
- For elderly patients or those with fragile skin, consider adding codes for risk factors if clinically relevant 5