Lateral ulnar collateral ligament of the elbow: optimization of evaluation with two-dimensional MR imaging.

PURPOSE To compare, in a cadaveric model, magnetic resonance (MR) imaging techniques with differing contrast and spatial resolution properties in the evaluation of disruption of the lateral ulnar collateral ligament (LUCL) at the elbow. MATERIALS AND METHODS LUCL tears were surgically created in eight of 28 cadaveric elbow specimens. All specimens underwent 1.5-T MR imaging with the following pulse sequences: T1-weighted spin echo (SE), intermediate-weighted fast SE, fat-suppressed T2-weighted fast SE, gradient-recalled echo (GRE) with high spatial resolution, intermediate-weighted fast SE with high spatial resolution, and fat-suppressed T1-weighted SE with intraarticular administration of gadopentetate dimeglumine (MR arthrography). All images were obtained in the oblique coronal plane. Two radiologists independently graded the LUCL with separate and side-by-side assessment. RESULTS Areas under the receiver operating characteristic curve were as follows for readers A and B, respectively: T1-weighted SE imaging, 0.64 and 0.62; intermediate-weighted fast SE imaging, 0.87 and 0.67; T2-weighted fast SE imaging, 0.68 and 0.69; GRE imaging, 0.56 and 0.68; MR arthrography, 0.84 and 0.85; and intermediate-weighted imaging with high spatial resolution, 0.92 and 0.88. Interobserver reliability was poor with T1-weighted SE imaging (kappa = 0.13) and GRE imaging (kappa = 0.18), fair with T2-weighted fast SE imaging (kappa = 0.36), and moderate with MR arthrography (kappa = 0.46), intermediate-weighted fast SE imaging (kappa = 0.55), and intermediate-weighted imaging with high spatial resolution (kappa = 0.59). CONCLUSION Intermediate-weighted imaging with high spatial resolution and MR arthrography showed the greatest overall ability to enable the diagnosis of LUCL tears.