This injury is the final stage of the continuum of carpal ligamentous injuries first explained by Mayfield, Johnson and Kilcoyne in 1980. Progressive hyperextension of the wrist will result in a predicted pattern of injury. The four stages are as follows:
1. Scapholunate dissocation
2. Perilunate dislocation
3. Perilunate and triquetral dislocation
4. Lunate dislocation
The lunate dislocation is the most severe stage.