Flexion-extension radiographs

Flexion-extension radiographs are X-ray images obtained in different positions, usually while bending forward and backward. They assess changes in vertebral alignment during movement when a clinical question about segmental mobility or instability needs clarification as part of a broader evaluation.

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Meaning on imaging

Unlike an X-ray obtained in one position, this examination compares several postures. In the lumbar spine, it may show whether vertebral slippage changes as the person bends. Movement is performed according to the imaging team's instructions and within limits considered appropriate for the clinical situation.

Indications and assessment

A referring clinician may consider it for spondylolisthesis, suspected instability or selected postoperative situations. It is not an automatic investigation for every episode of back pain. Recent trauma, a possible fracture and other contraindications must be considered before asking the person to move through different spinal positions.

Limitations and interpretation

Pain and apprehension can limit movement and underestimate segmental mobility. A lack of visible change therefore does not exclude every form of instability. Interpretation criteria vary with the region and clinical question. Comparing standing and lying-down examinations can sometimes add information during specialist assessment, without making additional imaging necessary for everyone.

Role of TAGMED care

At TAGMED, results may inform precautions for physical care. Suspected abnormal mobility needs clarification before traction or a technique that loads the segment. This examination does not demonstrate that a vertebra should be manipulated. Decisions require the whole assessment, including symptoms, neurological findings and the purpose of the proposed treatment.

Frequently asked questions

Does the examination show the nerves?

X-rays mainly show bone; MRI may address selected questions about nerves.

Should I force movement for a better image?

No. Follow instructions and report pain or neurological symptoms to the team.

Does it use X-rays?

Yes. Its justification considers the expected information as well as radiation exposure.

Is it suitable after every neck injury?

No. Suspected traumatic instability requires a specific medical imaging pathway.

Does a normal result permit every treatment?

No. Medical history, other images and clinical examination remain necessary before deciding on care.

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.