OBJECTIVE: The purpose of our study was to evaluate the effectiveness of conventional radiography and CT for explaining the osseous causes of elbow stiffness. MATERIALS AND METHODS: Two independent readers analyzed loose bodies and osteophytes on conventional radiography and CT (or CT arthrography) of the elbow in 94 consecutive patients (71 men, 23 women; mean age, 41 years; range, 18-68 years). Arthroscopic or surgical correlation was available in 58 (62%) patients. In all 94 patients, the expected restriction of motion was measured on images and correlated (Pearson's correlation) with the clinical restriction of motion. Kappa statistics were performed for interobserver agreement. RESULTS: Accuracy for detecting loose bodies was 67% with conventional radiography and 79% with CT. Differences in accuracy were most pronounced for detecting loose bodies in the posterior joint space (64% for conventional radiography vs 79% for CT). Accuracy for detecting osteophytes was 69% with conventional radiography and 76% with CT. Expected restriction of motion on conventional radiography correlated significantly with clinical restriction for only one reader for flexion (R = 0.21, p = 0.04). Expected restriction of extension on CT correlated significantly with clinical restriction of motion by both readers (R = 0.34 and 0.33, p = 0.001 and 0.001, respectively). Expected restriction of flexion on CT correlated significantly by one reader (R = 0.24, p = 0.02). Interobserver agreement with regard to detection of both loose bodies and osteophytes was higher for CT (kappa = 0.83 and 0.76) than for conventional radiography (0.64 and 0.60). CONCLUSION: CT is more effective than conventional radiography in explaining the osseous causes of elbow stiffness.