| S81.051 | Open bite, right knee | NON-BILLABLE CODE |
| S81.051A | Open bite, right knee, initial encounter | BILLABLE CODE |
| S81.051D | Open bite, right knee, subsequent encounter | BILLABLE CODE |
| S81.051S | Open bite, right knee, sequela | BILLABLE CODE |
| S81.052 | Open bite, left knee | NON-BILLABLE CODE |
| S81.052A | Open bite, left knee, initial encounter | BILLABLE CODE |
| S81.052D | Open bite, left knee, subsequent encounter | BILLABLE CODE |
| S81.052S | Open bite, left knee, sequela | BILLABLE CODE |
| S81.059 | Open bite, unspecified knee | NON-BILLABLE CODE |
| S81.059A | Open bite, unspecified knee, initial encounter | BILLABLE CODE |
| S81.059D | Open bite, unspecified knee, subsequent encounter | BILLABLE CODE |
| S81.059S | Open bite, unspecified knee, sequela | BILLABLE CODE |
