ICD-10-CM > S00-T88 > S80-S89 > S86 > S86.1 > S86.19 > S86.191 S86.191 Other injury of other muscle(s) and tendon(s) of posterior muscle group at lower leg level, right leg Non-Billable/Non-Specific Codes S86.191A..., initial encounterS86.191D..., subsequent encounterS86.191S..., sequela