It is less often encountered than dorsal intercalated segmental instability.
The tendon sheath of extensor carpi ulnaris was also inflamed. There was dorsal tilt of lunate bone with angle measuring greater than 30 degrees with associated mild dorsal placement of capitate bone in relation to the radius. Mild increased signal intensity seen within the short radiolunate ligament and deltoid/arcuate ligament with also evidence of laxity seen. Considering these findings, the diagnosis of dorsal intercalated segmental instability.