ICD-10-CM > S00-T88 > S50-S59 > S56 > S56.0 > S56.01 > S56.011 S56.011 Strain of flexor muscle, fascia and tendon of right thumb at forearm level Non-Billable/Non-Specific Codes S56.011A..., initial encounterS56.011D..., subsequent encounterS56.011S..., sequela