ICD-10-CM > S00-T88 > S30-S39 > S31 > S31.0 > S31.05 > S31.051 S31.051 Open bite of lower back and pelvis with penetration into retroperitoneum Non-Billable/Non-Specific Codes S31.051A..., initial encounterS31.051D..., subsequent encounterS31.051S..., sequela