CRITERIA FOR DIAGNOSING DISTAL RADIOULNAR JOINT SUBLUXATION BY COMPUTED-TOMOGRAPHY

Bilateral wrist computed tomography (CT) was performed in 30 patients with suspected unilateral distal radioulnar joint (DRUJ) subluxation t o evaluate dynamic DRUJ CT scanning with a straight elbow. Five CT cri teria for diagnosing dorsovolar subluxation were examined, Maximum act ive supination and pronation on a conventional scanning table yielded satisfactory rotation (mean +/- SD, 119 degrees +/- 29 degrees) at the DRUJ, thus permitting a dynamic diagnosis of DRUJ subluxation, The ra dioulnar line method and the congruity method frequently yielded false positive results compared with bilateral diagnosis and were unreliabl e. Modifications of these two methods achieved sensitivity and specifi city comparable to the epicenter method. We recommend the modified rad ioulnar line method for diagnosing dorsovolar subluxation using unilat eral CT because of its excellent sensitivity and specificity combined with ease of technique.