ICD-10-CM > S00-T88 > S60-S69 > S66 > S66.3 > S66.39 > S66.399 S66.399 Other injury of extensor muscle, fascia and tendon of unspecified finger at wrist and hand level Non-Billable/Non-Specific Codes S66.399A..., initial encounterS66.399D..., subsequent encounterS66.399S..., sequela