Progressive patterns of degenerative arthritis in scaphoid nonunion demonstrated by three-dimensional computed tomography.

Degenerative arthritis following scaphoid nonunion was studied in 28 patients (29 wrists) using X-ray computed tomography and three-dimensional computed tomography (3-DCT). Degenerative changes were observed in 18 wrists with plain radiography and 27 wrists with 3-DCT. 3-DCT imaging more readily revealed osteophyte formation in osteoarthritis than plain radiography. 3-DCT images showed degenerative changes in the distal fragment of the scaphoid earlier than plain radiography. We found three stages of osteophyte formation in the radioscaphoid joint using 3-DCT. In the first stage, a linear osteophyte formed along the most radial portion of the distal fragment of the scaphoid. In the second stage, the radial styloid became pointed. In the third stage, the osteophyte on the distal fragment enlarged and lay over the dorsum of the radioscaphoid joint and other intercarpal joints.