| Proximal phalanx base fracture | |||
| Intraarticular | I | Nondisplaced | |
| II | Comminuted / Central Impaction | ||
| III | Marginal with Subluxation | Dorsal Segment Failure | |
| Palmar Segment Failure | |||
| Collateral ligament Failure | |||
| IV | Fracture Dislocation | Dorsal Fracture Fragment | |
| Palmar Fracture Fragment | |||
| Central impaction | |||
| Dorsal and palmar fragments | |||
| Collateral ligament fragment | |||
| V | Longitudinal Split | ||
| Extraarticular | |||