Dorsal intercalated segment instability (DISI) is a deformity of the

wrist In human anatomy, the wrist is variously defined as (1) the carpus or carpal bones, the complex of eight bones forming the proximal skeletal segment of the hand; "The wrist contains eight bones, roughly aligned in two rows, known as the carpal ...

where the

lunate bone The lunate bone (semilunar bone) is a carpal bone in the human hand. It is distinguished by its deep concavity and crescentic outline. It is situated in the center of the proximal row carpal bones, which lie between the ulna and radius and the han ...

angulates to the dorsal side of the hand.

Causes

The main causes of DISI are: *Wrist trauma, with or without a fracture ** Scaphoid fracture: bony DISI ** Distal radius fracture: compensatory DISI **

Malunion A malunion is when a fractured bone does not heal properly. Some ways that it shows is by having the bone being twisted, shorter, or bent. Malunions can occur by having the bones improperly aligned when immobilized, having the cast taken off to ...

of radius fracture: adaptive DISI * Scapholunate ligament instability: ligamentous DISI

References

{{reflist Orthopedics