About an elbow CT scan
The elbow is the joint where the upper arm bone (humerus) meets the two forearm bones, the radius and ulna. It works as a hinge for bending and straightening, and also lets the forearm rotate to turn the palm up and down. A CT (computed tomography) scan uses X-rays and a computer to make detailed cross-section pictures of the bones, which can be turned into 3D images. CT shows bone in more detail than any other scan.
The most common reason for an elbow CT is a fracture. Many elbow fractures are seen on X-ray, but some, especially fractures of the radial head, the coronoid (a small piece of the ulna at the front of the joint) and the lower end of the humerus, can be complex or hard to see. A CT shows exactly how the bone has broken, which helps surgeons decide on treatment and plan an operation, particularly after a dislocation. It is also used to check fracture healing.
A CT may also be used to look at:
- arthritis and bone spurs that limit movement, including before surgery to free up a stiff elbow
- loose bodies, small pieces of bone or cartilage floating in the joint that can cause locking or catching
- extra bone forming in the soft tissues after an injury or surgery (heterotopic ossification)
- planning for elbow replacement
For tendon, ligament and nerve problems, such as tennis or golfer’s elbow, an elbow MRI or ultrasound is usually better. You can read more in our article on elbow imaging. When you book, choose the left or right side.
What happens during the scan
Depending on your comfort and the scanner, you either lie on your front with your arm stretched above your head, or on your back with your arm by your side. Pads are used to help you keep your arm still. The radiographer controls the scanner from the next room, but can see, hear and talk to you throughout. If you have a cast or splint, it can usually stay on. The scan itself takes only a few minutes. Contrast dye is not usually needed; where contrast is needed, it is charged separately.
Is CT safe?
CT uses X-rays, which are a type of ionising radiation. An elbow CT gives a low dose, because the area scanned is small and, with the arm positioned away from the body, far from the organs most sensitive to radiation. The risk from a single scan is very small, and every CT scan is checked by a radiologist or radiographer to make sure the benefit of the scan outweighs the risk, as required by the Ionising Radiation (Medical Exposure) Regulations. If you have had other CT scans recently, tell us when you book.
What the scan can show
An elbow CT can help to look at:
- complex and hidden fractures, including the radial head and coronoid
- fractures after a dislocation
- fracture healing and problems after surgery
- osteoarthritis and bone spurs
- loose bodies in the joint
- heterotopic ossification
- planning for elbow replacement
When to get urgent help: go to A&E if your elbow looks misshapen after an injury, you cannot move it, or your hand or fingers feel numb, cold or look pale. Do not wait for a private scan.
Preparing for your scan
No special preparation is needed, and you can eat and drink normally. Remove watches and bracelets before your appointment. Upload any previous X-ray or scan reports and letters from your surgeon when you book, and remember to choose the correct side.
Wear loose, comfortable clothing without metal zips, poppers or buttons, and leave jewellery at home, as metal in the scan area can affect the pictures. You may be asked to change into a gown. Unlike MRI, CT is not affected by pacemakers or most metal implants, and the scanner is a short open ring rather than a tunnel, so it is usually easier for people who feel anxious in enclosed spaces.
Tell the team before your scan if you are, or might be, pregnant or breastfeeding, if you have kidney problems, diabetes (especially if you take metformin), asthma, thyroid problems or allergies, or if you have had a reaction to contrast dye before. If you need contrast, you may be asked for a recent kidney blood test result.
Frequently asked questions
Why do I need a CT if my X-ray showed the fracture?
A CT shows the exact shape and position of the broken pieces, especially where the fracture enters the joint. This helps your surgeon decide whether you need an operation and how to do it.
Is CT or MRI better for my elbow?
CT is best for the bones, such as fractures, bone spurs and loose bodies. MRI is better for tendons, ligaments and nerves. Your referrer will say which is needed; if you are unsure, contact us before booking.
Do I need to choose a side?
Yes. Choose the left or right elbow when you book. If both elbows need scanning, contact us so the centre can plan the appointment.
Do I need a referral?
Because CT uses radiation, each scan has to be justified by a qualified professional before it can go ahead. Upload a referral from your GP or consultant when you book if you have one. If you do not, select “no referral” and the scanning centre will review your request and confirm the next steps with you, which may include arranging a referral.
Sources
- Diagnostic accuracy of fat pad sign, X-ray, and computed tomography in elbow trauma (PMC)
- NHS – Elbow and arm pain
- NHS – Tennis elbow
- NHS – CT scan
- UKHSA – Patient dose information: guidance
The information on this page has been gathered from various sources and is provided for general information only. It is not medical advice. TOP MRI is not liable for the accuracy or completeness of this information. Please speak to your doctor or the scanning centre about your own situation.