| S12.131A | Unspecified traumatic nondisplaced spondylolisthesis of second cervical vertebra, initial encounter for closed fracture | BILLABLE CODE |
| S12.131B | Unspecified traumatic nondisplaced spondylolisthesis of second cervical vertebra, initial encounter for open fracture | BILLABLE CODE |
| S12.131D | Unspecified traumatic nondisplaced spondylolisthesis of second cervical vertebra, subsequent encounter for fracture with routine healing | BILLABLE CODE |
| S12.131G | Unspecified traumatic nondisplaced spondylolisthesis of second cervical vertebra, subsequent encounter for fracture with delayed healing | BILLABLE CODE |
| S12.131K | Unspecified traumatic nondisplaced spondylolisthesis of second cervical vertebra, subsequent encounter for fracture with nonunion | BILLABLE CODE |
| S12.131S | Unspecified traumatic nondisplaced spondylolisthesis of second cervical vertebra, sequela | BILLABLE CODE |
