ICD-10-CM > S00-T88 > S50-S59 > S56 > S56.3 > S56.30 > S56.309 S56.309 Unspecified injury of extensor or abductor muscles, fascia and tendons of unspecified thumb at forearm level Non-Billable/Non-Specific Codes S56.309A..., initial encounterS56.309D..., subsequent encounterS56.309S..., sequela