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HealthInfo Canterbury

Your wrist bones

wrist bonesYour wrist is made up of eight small bones (called the carpal bones). Each carpal bone has a specific name, shown in the image on the right.

The carpal bones connect with the two long bones in your forearm (the radius and ulna). Your wrist moves where they connect.

This makes your wrist a very complex structure, as there are many different joints within it.

If any one of your carpal bones breaks, it can change position slightly, causing pain and problems with movement. Occasionally it can also lead to arthritis.

Causes of a broken wrist

A broken wrist usually happens from falling on to an outstretched hand. Serious accidents, such as car accidents, motorcycle accidents, or falls from a ladder cause more serious breaks. Weak bones (for example, in someone with osteoporosis) tend to break more easily.

If you break your wrist without significant force, your doctor may recommend checking if you have osteoporosis. If you meet the criteria, they may send you for a bone density scan.

Any one of the 10 bones in your wrist can break, but the most common bone to break is the radius, in your forearm. This is called a distal radius fracture.

Another common wrist fracture is a scaphoid fracture, which is a break in one of your small carpal bones. This can be difficult to diagnose, and there is a risk a scaphoid fracture might not heal.

Your wrist can break in many different ways, and some breaks are worse than others. How bad a break it is depends on how many pieces a bone breaks into, whether they are stable or move around a lot, and whether the broken ends of the bone are still in the right place.

Diagnosing a broken wrist

If you have broken your wrist it will be painful and swollen. It may be hard to use your hand or wrist. Your wrist may seem to be deformed, because it is swollen or a bone is out of place. You may feel pain just where it is broken, or whenever you move your fingers. Your fingers may tingle or your fingertips may be numb.

Some people can still move or use their hand or wrist and assume they have just sprained it. The break may only be diagnosed some weeks later when they see a doctor because the pain isn't going away, or they can't move their wrist as well as usual. This is more common with a broken scaphoid bone.

If you think you may have broken a bone in your wrist it is important to see a doctor.

Your doctor will ask about how your injury happened, look at your hand, and take X-rays to find out which bone is broken and what kind of break it is.

Because it can be difficult to see some wrist fractures in X-rays, your doctor may put your hand in a cast then ask you to return a week later for another X-ray. They may also X-ray above and below where you are sore, to check if you have any other nearby injuries.

It is possible you will also have a CT scan, which can show a complex break more clearly, or an MRI, to show any soft tissue injury.

On the next page: How is a broken wrist treated?

Written by HealthInfo clinical advisers. Endorsed by orthopaedic surgeon, Canterbury DHB. Page created March 2017.


Page reference: 348063

Review key: HIWAH-240323