CT Imaging of the Sternoclavicular Joint
CT of the sternoclavicular joint demonstrates bony anatomy, structural abnormalities, and pathologic conditions including trauma, infection, neoplasm, and arthropathy with superior detail compared to plain radiography.
What CT Shows
CT imaging of the SC joint provides detailed visualization of:
Bony structures and alignment: The medial clavicle, sternum, and first rib articulation are clearly delineated, allowing assessment of joint congruity and positioning 1
Traumatic injuries: CT confirms the direction and severity of dislocations (anterior versus posterior displacement of the medial clavicle relative to the sternum), subluxations, and associated fractures 2
Structural pathology: Erosions, sclerosis, joint space narrowing, soft-tissue ossification, and degenerative changes are well-visualized 1, 3
Soft tissue abnormalities: While primarily a bone imaging modality, CT can identify masses, abscesses, and calcifications in periarticular soft tissues 1
Clinical Utility
CT is the preferred imaging modality when plain radiographs are inconclusive for SC joint pathology 1. The examination offers several advantages:
Superior diagnostic accuracy: CT demonstrates abnormalities better than conventional tomography and provides additional diagnostic information in the majority of patients 1
Efficiency: Requires less examination time and causes less patient discomfort compared to linear tomography 1
Critical for treatment planning: Cross-sectional imaging is essential to distinguish true SC joint instability from medial clavicular physeal or metaphyseal fracture-separation, which have different treatment approaches and outcomes 4
Emergency assessment: In posterior SC joint dislocations, CT rapidly confirms the displacement direction, which is critical since the posteriorly displaced medial clavicle can compress vital mediastinal structures including great vessels 2, 3
Technical Considerations
The complex saddle-shaped anatomy of the SC joint makes it difficult to evaluate on plain radiographs 5. CT overcomes this limitation by providing multiplanar reformatted images that clearly show the joint space and surrounding structures 1. This is particularly important given the proximity of critical vascular structures posterior to the joint 4.