Scaphoid fractures and Kienbock's disease of the lunate: MR imaging with histopathologic correlation.

Thirteen patients with scaphoid fractures and four patients with Kienbock's disease of the lunate underwent magnetic resonance imaging (MRI) prior to surgery. A total of 28 specimens had MR-histologic correlation. Biopsy specimens obtained by curettage provided pathologic correlation. MRI proved accurate in prospective evaluation of bone viability for both scaphoid fractures and Kienbock's disease. Normal marrow signal was shown to correlate with the presence of osteoid and osteocytes on light microscopy and a surface layer of fluorescence reflecting tetracycline uptake in viable bone. Decreased marrow signal corresponded to non-viable trabeculae with scant osteoid, without osteocytes and no tetracycline labeling. By virtue of its accurate identification of avascular necrosis, MRI may prove valuable in predicting prognosis for patients with scaphoid fractures and Kienbock's disease of the lunate.