Approach to the Radiological Imaging of the Elbow

Abstract

The elbow is a complex joint made by the union of three separate joints (a simple hinge joint, a ball-and-socket joint, and a pivot joint). These joints are connected by a single, large capsule and several ligaments. The biomechanical features of these structures allow for complex movements of flexion-extension and pronation-supination (Capo et al. 2014; Wegmann et al. 2014; Sonin et al. 1996). For these reasons, the elbow represents a challenge in terms of diagnosis, therapy, and rehabilitation. Thus, there is a specific clinical need of high-level imaging, aimed to stage correctly the lesions that can be encountered. The technological advancements and the figure of dedicated musculoskeletal radiologists helped to address some critical issues. The transition from analogic to digital radiology, the advent of the multi-detector computed tomography (MDCT), and the use of intra-articular contrast media (CT arthrography and magnetic resonance [MR] arthrography) have certainly help increasing diagnostic capabilities both acutely and chronically. The high resolution of MDCT images and the new capabilities of post-processing as the reconstruction in various planes of the space (multiplanar reconstruction [MPR]) and the generation of three-dimensional images have significantly helped to improve the diagnosis in the acute elbow trauma (O’Driscoll 2000; Tarassoli et al. 2013; Sormaala et al. 2014). Of note, more recent CT scans, despite the large number of images generated by these systems, allowed for a significant reduction of the radiation exposure, which is particularly important in younger patients and in those who need repeated examinations. MRI has always been considered the pivotal imaging modality in musculoskeletal disease. It is probably the modality that most has taken advantage of technological developments, including new three-dimensional imaging sequences, innovative softwares, and improvement of receiving coils, which led to an increased diagnostic performance in most fields of musculoskeletal pathology. Furthermore, the extreme rapidity of MR sequences allows for performing imaging also in patients with painful joints, taking advantage of posttraumatic joint effusion to achieve an arthrographic-like effect.