Open a PDF version to print this topic

HealthInfo Waitaha Canterbury

Broken kneecap (fractured patella)

Popoki tāwhatiwhati

Woman with broken kneecap, with her leg in a brace, using crutchesYour kneecap (or patella) is the bone that sits in front of your knee joint. It's held in place by a tendon.

A broken kneecap is quite a common injury because your kneecap acts as a shield to protect your knee joint. A break usually happens because of a direct blow to the bone, such as falling onto a hard surface and landing on your knees.

A broken kneecap is a serious injury and often needs surgery. In the long-term, it can cause arthritis in your knee.

This page explains what happens when your kneecap breaks. Other pages explain what happens when other bones in your knee break.

Diagnosing a broken kneecap

If you have one or more of the following symptoms after an injury, you may have broken your kneecap:

Your doctor or physiotherapist will diagnose a broken kneecap by listening to your explanation of what happened, examining you and looking at an X-ray of your knee.

Treating a broken kneecap

How your broken kneecap is treated depends on what the fracture looks like.

If the break is stable (the bones will not move much) and you can fully straighten and raise your leg, you may be treated with a brace. This is called non-operative management.

The brace will limit the movement of your leg so the bones can heal.

It may be uncomfortable to put weight on your leg until the bone is completely healed, which may take six to eight weeks or even longer. Some people use crutches during this time.

If your fracture is unstable (meaning the bones could move around a lot), you might need surgery.

Whether or not you have surgery, you'll need some time off work. How long will depend on your specific treatment, what your job involves and whether there are light duties you can do.

Self-care for a broken kneecap

Whether or not you have surgery, there are some things you can do to make sure you recover as quickly and as well as possible.

Make sure you follow the advice of your doctor, physiotherapist or other health professional about rehabilitation and exercises. This is very important, as not following instructions may mean your broken kneecap doesn't heal or heals in the wrong position. This can lead to continuing pain and further problems.

Keep your leg raised as much as possible for the first 24 to 48 hours and apply ice for 15 minutes every four to five hours.

If you smoke, stop smoking. Smoking affects how well your body can make new blood vessels, which reduces your chances of healing well.

Make sure you keep your wound, and cast if you have one, clean, dry and covered.

Follow the instructions for any pain relief medicine you're given, and avoid any anti-inflammatory medicines, as they can slow down bone healing.

On the next page: Surgery for a broken kneecap

Written by HealthInfo clinical advisers. Last reviewed July 2022.


See also:

Broken bones first aid

Page reference: 132280

Review key: HIHIL-240273