VISI

Volar intercalated segment instability (VISI) is a type of instability involving the wrist. It is less often encountered than dorsal intercalated segment instability (DISI).

Clinical presentation

It presents in most cases with nonspecific wrist pain and a "clunking" on the ulnar deviation of the wrist.

Pathology

VISI can occur because of a disruption of radiocarpal ligaments on the ulnar side of the wrist. The main ligaments involved in this instability are thought to be the ulnar half of the volar arcuate ligament and the lunotriquetral ligament . It may be static or dynamic.

Radiographic features

The main radiographic features are a volar rotation of the lunate and dorsal rotation of the capitate and hamate.

Radiograph

Abnormal carpal angles are seen on any lateral or sagittal imaging of the wrist when the wrist is in a neutral position:

• scapholunate angle <30°
• capitolunate angle >30°

Treatment and prognosis

The mainstay of treatment is surgery, either by early reduction and casting with K-wires or by capitolunate fusion.

See also

• dorsal intercalated segment instability (DISI)

Siehe auch:

• DISI-Fehlstellung
• Scapholunäre Dissoziation
• Lunatummalazie
• perilunäre Instabilität

und weiter:

• perilunäre Luxation
• Lunatumluxation
• scapholunärer Winkel
• radiologisches muskuloskelettales Curriculum
• capitolunärer Winkel