CT (computed tomography) produces multiple cross‑sectional (2D) X‑ray slices of the body. A 3D CT is a post‑processed reconstruction of those slices into a volumetric image, giving realistic spatial views for surgical planning, complex fractures, vascular mapping and anatomy assessment. 3D views improve visualization and measurements but stem from the same scan data and require extra processing rather than a different scan.

For a right shoulder CT, the patient lies supine, head-first into the scanner with the right shoulder centered in the gantry. The right arm is positioned alongside the body in neutral or slight external rotation (as directed) and immobilized to reduce motion. Padding supports and instructions to stay still (and a brief breath-hold if requested) optimize imaging of the glenohumeral joint and nearby structures.

A 3D CT scan appointment typically takes 15–30 minutes overall. The actual image acquisition is usually brief — seconds to a few minutes — but positioning, registration and tech checks add time. If intravenous contrast is used, allow extra time for injection, monitoring and possible blood tests, extending the visit to 45–60 minutes. Results are reported later by a radiologist.

A CT scan can clearly show shoulder bone problems—fractures, joint alignment, arthritis, bone tumors and complex anatomy—and is useful for pre‑operative planning. It’s less sensitive for soft‑tissue injuries like rotator cuff or labral tears; MRI (or CT arthrography if MRI isn’t possible) better evaluates tendons, ligaments and cartilage. CT involves radiation, so it’s used when detailed bony detail is needed.

A 3D CT scan uses X-rays and computer reconstruction to produce volumetric images. You lie on a motorized table that moves through a doughnut-shaped scanner while the X-ray tube rotates around you. Breath-holds and an intravenous contrast dye may be used to reduce motion and highlight vessels or organs. The scanner acquires thin slices which software assembles and renders as 3D views for diagnosis and surgical planning.

A 3D CT scan is generally safe but involves ionizing radiation, which slightly increases lifetime cancer risk, especially with repeated scans or in children. If contrast dye is used, possible side effects include allergic reactions (rash, itching, rarely severe anaphylaxis), nausea, metallic taste, or kidney injury—particularly in people with preexisting kidney disease. Mild discomfort, injection-site pain or contrast extravasation can also occur.