The best imaging for the sternoclavicular joint is computed tomography (CT), ideally with thin slices and 3‑D reconstructions, because it shows bony detail and dislocation clearly. MRI is preferred when soft‑tissue, ligamentous injury, marrow change or infection is suspected. Plain radiographs are often inadequate; ultrasound can detect superficial effusion but is operator‑dependent.

Diagnosis combines medical history and focused physical exam—localized sternoclavicular tenderness, swelling, crepitus and pain with shoulder movement or cross‑body adduction. Imaging starts with plain X‑ray but CT gives detailed bone/dislocation assessment; MRI evaluates soft tissue, cartilage or infection; ultrasound can detect effusion. Blood tests (CBC, CRP) and joint aspiration are used if infection is suspected or red flags (fever, systemic illness) are present.

A sternum MRI visualizes the breastbone’s bone marrow, surrounding soft tissues, cartilage, nearby joints and mediastinal structures. It detects marrow edema, occult fractures, infection (osteomyelitis), tumors or metastases, inflammatory conditions, and postoperative or chest‑wall involvement. MRI also shows muscles, ligaments and vascular/neural relationships, helping characterize lesions and guide treatment when CT or X‑ray are inconclusive.

The sternoclavicular (SC) joint injury severity ranges from minor sprains to potentially life‑threatening posterior dislocations or infection. Anterior dislocations often cause pain and deformity but are less dangerous; posterior dislocations can compress the trachea, major vessels or esophagus and require urgent care. Septic arthritis of the SC joint also needs prompt antibiotics or surgery. Seek emergency evaluation for breathing, swallowing, vascular or severe pain.

Sternoclavicular arthritis commonly causes pain and tenderness at the joint where the collarbone meets the breastbone, often with swelling, warmth, and visible or palpable deformity. Movement of the shoulder or arm is limited, with stiffness, creaking (crepitus), and pain that may radiate to the neck, shoulder, or chest. Occasionally inflammation causes fever and general malaise.

The best scan depends on the suspected cause: X-ray is first-line for fractures and joint-space changes; MRI is best for cartilage, ligaments, menisci and other soft-tissue problems; ultrasound is useful for tendons, effusions and guided procedures; CT gives detailed bone imaging or helps when MRI isn’t possible. Your clinician will choose based on symptoms, exam and medical history.