ICD-10-CM > S00-T88 > S20-S29 > S29 > S29.0 > S29.01 > S29.012 S29.012 Strain of muscle and tendon of back wall of thorax Non-Billable/Non-Specific Codes S29.012A..., initial encounterS29.012D..., subsequent encounterS29.012S..., sequela