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Diagnosis of knee pain

It is sensible to have knee pain examined by an experienced doctor.

How is knee pain diagnosed? 

If you are worried about your knee pain, it is important to discuss your concerns with your GP or a specialist. They can then help diagnose the cause of your knee pain and recommend treatment based on your needs and requirements. 

We discuss the importance of an accurate diagnosis and how knee pain can be diagnosed. 

The various causes of knee pain can almost always be reliably diagnosed by an experienced musculoskeletal doctor or physiotherapist. To reach a diagnosis, a careful history of any previous pains or issues with joints is undertaken, as well as performing a physical examination.

Fortunately, there are effective treatment options and pain relief available for knee pain, including knee replacement and specialist exercises managed by a physical therapist.

Not all knee pain is equal. Even the phrase “knee pain” is a fairly generic way of describing a wide range of possible symptoms. For example, the pain you have may be:
  • Dull or sharp (aching knee pain);
  • Infrequent or constant (aching knee pain);
  • Generalised or localised (pain above knee cap), and
  • Short or long-term.

Mild, short-term knee pain is often a bit simpler to manage and treat than severe or long-term pain. However, any knee pain can significantly affect the quality of your life.

Before any treatment is given, an accurate diagnosis is crucial. Knowing the reason(s) you’re getting pain in your knee will ensure that you are given the treatment you need. 

Doctors are good listeners. By asking you questions and listening carefully to your answers they will often be able to get a good preliminary idea of what is causing your pain before they even physically examine your knee.

Diagnostic tests will often then be needed to either confirm diagnosis and/or to help assess the extent of any damage or trauma.  

A physical examination of your knee is an important part of any assessment. As part of this, your doctor may bend or move your leg and knee into various positions to see how the joint is functioning and when and where you are getting pain.

To help with diagnosis, additional investigations such as X-rays or scans may be needed. These include:

  • X-ray: X-rays are a type of radiation. They can be used to produce images that show the bones of the knee clearly, and are useful when querying a fracture, dislocation or arthritic damage to the knee. There are a number of positions the knee may be X-rayed from, including from the front, from the side and sometimes while you’re standing if the doctor wants to see how the joint looks when weight-bearing. Depending on your symptoms and the physical examination of your knee, your doctor may have both knees x-rayed to compare them with one another, or just the one causing you problems.
  • CT scan: Computerised tomography (CT) uses X-rays to produce cross-sectional images of the knee joint. These ‘slices’ can vary in width and are used to build up a very accurate three-dimensional image of the knee joint. The CT scanner looks a bit like a large doughnut, and the scan is done with you lying on a table with your knee in the centre of the hole. It’s important you keep as still as possible during the scan so that the images are clear. The scan itself usually takes around 20 minutes and no preparation is needed beforehand.
  • MRI scan: Magnetic resonance imagining (MRI) uses strong magnets and radio waves to produce very detailed images of the knee. Similar to CT, an MRI scan produces cross-sectional images of the knee. While CT scan is excellent for showing bone detail, an MRI scan gives more detail on the soft tissues. This makes it an excellent diagnostic choice if you’ve damaged a muscle, ligament or tendon. The scanner makes quite a loud thumping noise as it works, so you may be given some headphones to wear for your comfort.
  • Ultrasound: Uses high-frequency sound waves to create an image. Unlike other imaging options, ultrasound can be used to show movement of the joint in real time. Although many of the important structures of the knee can’t be seen using ultrasound, as they’re ‘hidden’ by bone, ultrasound can be used to examine some of the tendons, bursae (fluid-filled sacs) and muscles around the knee.
  • Arthroscopy: If your doctor thinks you may have damage to a cartilage or ligament, they may recommend an arthroscopy. This is a form of keyhole surgery, where a small cut is made in your knee and a thin tube (arthroscope) placed through it into the joint. The arthroscope has a bright light and camera at one end and allows the doctor to see clearly inside the knee joint. The advantage of arthroscopy is that surgical repair can be carried out if needed at the same time as the examination. Tiny surgical instruments can be inserted through the arthroscope to repair cartilage or ligament (e.g. anterior cruciate ligament) or to remove fragments of loose bone.

Once the cause of your knee pain has been determined, your doctor will talk with you about treatment options and advise you on the best treatment options to get you out of pain and back to normal again.

Knee pain is frustrating to live with, limiting your ability to do the things you love and preventing you from taking part in the sports or activities you enjoy.

We can help get you out of pain and back to doing the things you want. It’s easy to book a consultation online with one of our experienced knee doctors.

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