Dorsal intercalated segment instability
Dorsal intercalated segment instability is a deformity of the wrist where the lunate bone angulates to the dorsal side of the hand.
Causes
The main cause of DISI is wrist trauma, with or without a fracture:- Scaphoid fracture: bony DISI
- Distal radius fracture: compensatory DISI
- Malunion of radius fracture: adaptive DISI
- Scapholunate ligament instability: ligamentous DISI