Is the flexion-abduction-supination magnetic resonance imaging view more accurate than standard magnetic resonance imaging in detecting distal biceps pathology?

Abstract

Background and hypothesis: Partial biceps tendon pathology is difficult to diagnose. The flexion-abduction-supination (FABS) magnetic resonance imaging (MRI) view has been advocated to improve the accuracy of MRI investigation. The purpose of this study was to evaluate the accuracy of the FABS view MRI in the diagnosis of distal biceps tendon pathology.

Methods: The study included 50 patients with surgically confirmed distal biceps tendon pathology and 50 patients with other elbow disorders. In both groups, standard elbow MRI (retrospective review of previously obtained MRI data) was performed in half of the patients whereas FABS views MRI were obtained in the other half. These were evaluated by 2 independent musculoskeletal radiologists. The sensitivity and specificity of both MRI views were determined. Tendinosis and grade of rupture were reported from MRI and then compared with surgical findings.

Results: There were no significant differences in sensitivity and specificity in detecting partial distal biceps injuries when the FABS view MRI (sensitivity, 84%; specificity, 86%) and standard MRI (sensitivity, 76%; specificity, 98%) were compared. The interobserver reliability was 92% for the FABS view MRI with biceps pathology and 68% for standard MRI. In the control group, the interobserver reliability was 88% for the FABS view MRI and 96% for standard MRI. FABS MRI was significantly better regarding grade of injury.

Conclusions: No significant differences in sensitivity and specificity were found between the FABS view and standard elbow MRI in the diagnosis of partial distal biceps tendon injuries, with high sensitivity and specificity for both views. Inter-rater reliability was better for FABS views, and FABS views were significantly more accurate than surgical findings in grading the extent of pathology.

Keywords: FABS; MRI; biceps; distal; elbow; partial; rupture; tendon.