VISI
Also written as: VISI — volar intercalated segment instability
Volar intercalated segment instability; carpal instability pattern where lunate tilts toward the palm.
Full Definition
Volar intercalated segment instability (VISI) is a type of carpal instability where the lunate bone tilts in a volar (palmar) direction. This occurs when there is disruption of the ligamentous structures that normally maintain carpal alignment, particularly affecting the lunotriquetral joint. VISI is often associated with ulnar-sided wrist pain and may result from trauma or degenerative changes. The condition can be diagnosed through lateral radiographs showing the characteristic lunate tilt and may require surgical intervention for symptomatic cases.
Usage
Usage note: Often contrasted with DISI; ensure correct directional terminology when describing carpal instability patterns.
In Context
- "The lateral radiograph demonstrated VISI with a scapholunate angle of less than 30 degrees." — Radiology report
- "Following lunotriquetral ligament injury, the patient developed symptomatic VISI requiring arthrodesis." — Operative report