5 Imaging Techniques Used to Diagnose Bone Tumours

Most bone tumours are not cancer. But telling a harmless one from a serious one cannot be done on symptoms alone, and it cannot be done on a single scan either. These are the five imaging tests used to find out, and what each one is for.

Why imaging is the only way to be sure

Bone tumours cause a wide range of symptoms, and many of them look like ordinary problems. Pain that will not settle, swelling, a lump, or a bone that breaks after a minor knock. Plenty of harmless conditions cause the same things.

Some bone tumours are found completely by accident, on an X-ray taken for something else entirely. That is common and usually not a cause for alarm.

Imaging answers the questions that matter: where exactly is it, how big, is it growing into the surrounding tissue, is the bone weak enough to break, and does it appear anywhere else. A biopsy is often still needed for the final answer, but imaging decides whether one is required and where to take it from.

1. X-ray

The X-ray is the first test and remains the most useful single one.

It is quick, widely available and inexpensive. For an experienced doctor, a good quality X-ray often gives most of the answer on its own. Many typical benign lesions can be identified from the X-ray alone, and no further test is needed beyond keeping an eye on it.

What the X-ray shows is the pattern. Whether the edges of the lesion are sharp and well defined, which is reassuring, or blurred and ragged, which is not. Whether the bone has reacted around it. Whether the outer shell of the bone is intact.

Best for: the first look, and often the only test needed.

2. CT scan

A CT scan is a three dimensional X-ray. It takes many images and builds them into a detailed view of the bone.

Where the plain X-ray shows a flat picture, CT shows the bone from every angle. It shows exactly how much of the bone has been destroyed, whether the outer shell is broken through, and how much strength is left. That last point matters, because a bone weakened enough to break needs different management.

CT is also used to check whether anything has spread to the lungs, which is usually part of the assessment when a tumour may be malignant.

Best for: the detail of the bone itself, and measuring how much has been destroyed.

3. MRI

MRI uses magnets rather than X-rays, so there is no radiation. It is the best test for everything around the bone.

It shows the marrow inside the bone, the muscle around it, and the nerves and blood vessels nearby. It shows how far a tumour extends inside the bone, which is often further than the X-ray suggests, and whether it has grown out into the soft tissue.

A contrast dye is sometimes given through a vein, which makes areas of active tissue stand out. Most people tolerate it easily.

If surgery is being planned, MRI is what the surgeon uses to plan it, because it shows exactly where the tumour ends and healthy tissue begins.

Best for: soft tissue, marrow, and planning surgery.

4. Bone scan

A bone scan is a nuclear medicine test. A small amount of a radioactive tracer is injected into a vein, and it collects in areas where bone is actively turning over. A special camera then photographs the whole skeleton.

The point of it is coverage. Instead of looking at one bone, it looks at all of them at once. That is useful for answering one specific question: is this the only place involved, or are there others.

Bone turnover increases for many reasons, including healed fractures, arthritis and infection, so a hot spot does not by itself mean a tumour. It shows where to look more closely.

Best for: checking the whole skeleton in one test.

5. PET scan

A PET scan shows how active tissue is, rather than what it looks like. A tracer is injected, and tissue that is using a lot of energy shows up brightly.

It is used mainly in cancer, and only in selected cases for bone tumours. It can help show whether a tumour is active, whether it has spread, and whether treatment is working, since activity falls before the size changes.

It is often combined with CT in one machine, so the activity and the anatomy are seen together.

Best for: assessing activity and response to treatment.

Which test you actually need

You will not need all five. Most people need an X-ray, and some need one or two more. The tests are chosen to answer specific questions, not collected for the sake of it.

Symptoms worth getting checked

• Bone pain that continues at night or at rest, rather than only on activity.
• Pain that keeps getting worse over weeks or months.
• A lump on or near a bone, especially one that is growing.
• Swelling that does not settle.
• A bone that breaks after a very minor injury.
• Unexplained weight loss or fever alongside bone pain.

Most of the time these turn out to be something ordinary. They are still worth an X-ray.

Frequently asked questions

Are most bone tumours cancer?

No. Most are benign, and many cause few or no symptoms. Some are found by chance on an X-ray taken for another reason. Imaging is what separates the harmless ones from the ones that need treatment.

Can an X-ray alone diagnose a bone tumour?

Often it can, particularly for typical benign lesions where the pattern is recognisable and the edges are well defined. When the appearance is unclear, or the lesion looks aggressive, further imaging and usually a biopsy are needed.

What is the difference between a CT scan and an MRI here?

CT is better for the bone itself, showing how much has been destroyed and how much strength is left. MRI is better for everything around it, including the marrow, muscle and nerves, and it is what surgery is planned from. They answer different questions, which is why both are sometimes done.

Is a bone scan the same as an X-ray?

No. An X-ray photographs the structure of one area. A bone scan uses an injected tracer to show areas of active bone turnover across the whole skeleton, which answers whether more than one bone is involved.

Do I need a biopsy as well?

Often yes, when the imaging does not give a definite answer. The biopsy gives the final diagnosis. Where it is taken from matters a great deal, so it should be planned by the team who would carry out any surgery.

Getting bone pain assessed

Bone pain that continues at night, or a lump that is growing, should be looked at rather than watched. Call +91 6355 991 466 to arrange an assessment at Vedaant Orthopaedic Center, Surat.

Trusted sources and further reading

This article is general information reviewed by Dr Dev Padia. For more on the conditions and treatments mentioned, see the pages below.

• Advanced orthopaedic surgery — specialist diagnosis and treatment.
• Contact the clinic — to arrange an assessment.
• MedlinePlus: Bone Cancer and Tumours — US National Library of Medicine.
• OrthoInfo: Bone Tumor — American Academy of Orthopaedic Surgeons.

The information on this website is for general guidance and does not replace a personal medical consultation. Please consult a qualified doctor about your own symptoms.