Computed tomography

Imaging using X-rays and computer processing to produce cross-sectional images, particularly detailed for bone.

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Cross-sectional imaging with strong bone detail

Computed tomography, often called CT or a CAT scan, uses x-rays and computer processing. It reconstructs thin sections and different views of the spine. Its speed and bone detail are useful for selected fractures, surgical hardware assessment or procedure planning. MRI is better suited to some questions involving the spinal cord and soft tissues.

The examination is performed while lying on a table that moves through a ring. It is usually brief and may involve iodinated contrast depending on the question. Radiation exposure is one reason to request it only when it offers useful information. Report possible pregnancy, relevant allergies and kidney disease when contrast is planned. An impressive three-dimensional reconstruction still requires clinical interpretation and does not directly measure pain or identify every nerve problem.

Indications and interpretation

Before ordering the test, the clinician should identify the question it needs to answer and how the result could change decisions. Routine imaging for low back pain without warning signs does not necessarily improve care. A result describes structures; it does not measure all aspects of pain or a person's capacity to recover. Age, previous conditions, the affected side and the physical examination help distinguish a relevant abnormality from an incidental finding. More visible detail is useful only when interpreted appropriately.

After the results

The responsible clinician should explain which findings need action, follow-up or no particular intervention. Bringing previous studies can prevent unnecessary repetition. At TAGMED, imaging can help select or exclude particular care options; it cannot establish that traction, laser treatment or manual care will work. Decisions remain clinical and must consider contraindications. Progressive weakness, altered saddle sensation or a new inability to urinate must not wait for a routine imaging appointment: these symptoms need emergency assessment. Follow the preparation and safety instructions supplied by the imaging centre. Ask how and when results will be communicated rather than assuming that silence means everything was normal.

Frequently asked questions

Are CT and MRI interchangeable?

No. Their usefulness depends on the structures of interest and the clinical situation.

Does an abnormality necessarily explain pain?

No. Agreement with symptoms and examination findings must be checked.

Should previous results be brought?

Yes when available; comparison may prevent unnecessary repeat studies.

Who explains the report?

The responsible clinician interprets it within the whole clinical picture.

Does the test determine treatment?

It contributes to decisions but does not replace clinical assessment and discussion of options.

Educational information from The Spine Page. This entry does not replace an individual assessment. Documentary version: October 12, 2026. Sylvain Desforges, B.Sc., D.O., N.D., osteopath and naturopath.