| S12.121A | Other nondisplaced dens fracture, initial encounter for closed fracture | BILLABLE CODE |
| S12.121B | Other nondisplaced dens fracture, initial encounter for open fracture | BILLABLE CODE |
| S12.121D | Other nondisplaced dens fracture, subsequent encounter for fracture with routine healing | BILLABLE CODE |
| S12.121G | Other nondisplaced dens fracture, subsequent encounter for fracture with delayed healing | BILLABLE CODE |
| S12.121K | Other nondisplaced dens fracture, subsequent encounter for fracture with nonunion | BILLABLE CODE |
| S12.121S | Other nondisplaced dens fracture, sequela | BILLABLE CODE |
