There are several important causes of an abnormal lunate signal on MRI, the most frequent causes being Kienböck disease (25%), ulnar impaction syndrome (25%) and intraosseous ganglia (20%) 1. Appreciation of the pattern of bone signal change can often allow the correct diagnosis to be made.
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sclerosis (low T1 and T2) centrally and within the radial aspect of lunate
sclerosis can be diffuse
bone edema (high T2, intermediate T1) may be seen in the acute phase, particularly on the radial side
75% of cases are associated with negative ulnar variance
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sclerosis (low T1 and T2) localized to the proximal ulnar aspect of lunate
bone edema (high T2, intermediate T1)
chondromalacia of distal ulnar and proximal lunate cartilage
commonly associated with positive ulnar variance
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round T2 hyperintense regions
usually radial side of the lunate or distal lunate
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diffuse bone edema (high T2, intermediate T1)
linear fracture line (low T1 and T2)
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others
degenerative disease
inflammatory disease