ICD-10-CM Code for Subungual Hematoma
The ICD-10-CM code for subungual hematoma is S60.10 (for finger) or S90.10 (for toe), with additional specificity required for laterality and encounter type.
Code Structure and Specificity
The complete ICD-10-CM coding for subungual hematoma requires:
S60.1 - Contusion of finger with damage to nail
- S60.10XA - Initial encounter (unspecified finger)
- S60.11XA - Thumb (with laterality: 1 for right, 2 for left)
- S60.12XA through S60.19XA - Individual fingers with laterality
S90.1 - Contusion of toe with damage to nail
- S90.11XA through S90.12XA - Great toe (with laterality)
- S90.21XA through S90.22XA - Other toes (with laterality)
The seventh character extension is mandatory:
- A = Initial encounter
- D = Subsequent encounter
- S = Sequela
Clinical Context
While the provided evidence focuses primarily on onychomycosis (fungal nail infections) 1 and melanoma evaluation 2, the research literature confirms subungual hematoma as a distinct traumatic entity requiring drainage/trephination 3, 4, 5, 6, 7.
Key coding considerations:
- Document the specific digit involved (thumb vs finger, great toe vs other toe)
- Specify laterality (right vs left)
- Note encounter type (initial, subsequent, or sequela)
- Consider adding external cause codes (Chapter 20) to identify mechanism of injury
Common Coding Pitfalls
- Avoid unspecified codes when documentation allows for greater specificity - medical coders often default to unspecified codes due to time pressure or incomplete documentation 8
- Do not confuse with nail bed laceration codes (S61.3xx for finger, S91.2xx for toe) - these are separate injuries that may coexist
- Distinguish from chronic nail conditions like onychomycosis, which use different code categories (B35.1)
The coding accuracy depends heavily on clinical documentation specifying the exact digit and laterality at the time of encounter.