[Diagnosis and staging of lunate necrosis. A current review]

Recently, early diagnosis and staging of Kienböck's disease was mainly influenced by imaging techniques (CT and MRI). New findings led to the staging classification of Lichtman and Ross (1994) which is recommended in the following. MRI allows diagnosis of the reversible bone marrow edema (stage I), which often is equivocal in conventional radiography. High-resolution CT facilities a more precise imaging of later stages in Kienböck's disease including spongiosal sclerosis (stage II), fractures at the proximal pole (stage III A), and initial osteoarthrosis (stage IV). For therapeutic considerations, contrast-enhanced MRI is extremely useful in stages II and III A, whereas MRI is redundant in stages III B and IV. Carpal instability (stage III B) is sufficiently visualized using conventional radiograms exposed in the neutral position. This review article reveals the value and indications of CT and MRI.